testsAndMisc/linux_configuration/docs/security-hardening/DOCS-01-current-state.md
Krzysztof kuhy Rudnicki ad46fc85a5 pacman wrapper: drop list-file checks and docs after list retirement
digital-wellbeing e2a7176 removed the blocked-keyword, white and grey
lists. check_pacman_wrapper no longer looks for them, the VirtualBox note
stops citing pacman policy, and the docs drop the lists and greylist
challenge.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016Lhzv7c391mTKWfwU17V7Z
2026-10-17 18:46:17 +02:00

4.8 KiB

Part 1: Current State Analysis

1. /etc/hosts Protection System

Files involved:

Current Protection Layers:

  1. ✅ Immutable attribute (chattr +i)
  2. ✅ Canonical copy at /usr/local/share/locked-hosts
  3. ✅ Path watcher (hosts-guard.path) auto-restores on modification
  4. ✅ Read-only bind mount (hosts-bind-mount.service)
  5. ✅ Custom entries protection (blocks removal of blocked domains)
  6. ✅ Shell history suppression for unlock-hosts command

CRITICAL VULNERABILITY IDENTIFIED:

  • ❌ NO protection for /etc/nsswitch.conf - A user can simply edit nsswitch.conf and remove files from the hosts: line, completely bypassing ALL /etc/hosts protections without touching the hosts file itself!

Example bypass:

# Original: hosts: mymachines resolve [!UNAVAIL=return] files myhostname dns
# Tampered: hosts: mymachines resolve [!UNAVAIL=return] myhostname dns
# Result: /etc/hosts is completely ignored by the system

2. Midnight Shutdown System

Files involved:

Current Protection Layers:

  1. ✅ Immutable attribute on /etc/shutdown-schedule.conf
  2. ✅ Canonical copy at /usr/local/share/locked-shutdown-schedule.conf
  3. ✅ Path watcher restores config if tampered
  4. ✅ Schedule protection blocks making schedule more lenient
  5. ✅ Unlock script with psychological delay

VULNERABILITIES IDENTIFIED:

  • ❌ The unlock script explicitly tells users how to bypass: "sudo /usr/local/sbin/unlock-shutdown-schedule"
  • ❌ The schedule change logic is communicated in the error message
  • ❌ No protection against stopping/disabling the timer services
  • ❌ No protection against modifying the check script at /usr/local/bin/day-specific-shutdown-check.sh

3. Screen Locker (Python - External Repo)

File: /home/kuhy/src/testsAndMisc/python_pkg/screen_locker/screen_lock.py

Current Workout Types:

  1. Running - distance, time, pace validation
  2. Strength - exercises, sets, reps, weights, total calculation
  3. Table Tennis - duration, sets, points won/lost

VULNERABILITIES IDENTIFIED:

  • ❌ Running option too easy to fake - just enter plausible numbers
  • ❌ Table Tennis lacks real verification - no mathematical cross-check
  • ❌ Users can close the window via keyboard shortcuts (Alt+F4, etc.)
  • ❌ The unlock mechanism is too simple once you know the forms
  • ❌ Shutdown time adjustment is a REWARD for working out (can be exploited)

4. Pacman Wrapper

Files involved:

Current Protection:

  1. ✅ Wrapper lib integrity verification (SHA256)
  2. ✅ VirtualBox hardcoded check (cannot bypass via wrapper libs)
  3. ✅ Steam weekend-only restriction

Note: the package policy lists (blocked keywords, whitelist, greylist) were retired 2026-10-17; hosts/DNS blocking covers them.

VULNERABILITIES IDENTIFIED:

  • ❌ No automatic LeechBlock installation when browsers are detected
  • ❌ User can download .deb/.tar.gz and install manually

5. Block Compulsive Opening

File: periodic_background/digital_wellbeing/block_compulsive_opening.sh (507 lines)

Current Behavior:

  • Records first open per hour in state file
  • Blocks subsequent launches within same hour
  • Shows notification when blocked

CRITICAL VULNERABILITY:

  • ❌ App stays running indefinitely - User can:
    1. Open app once per hour (allowed)
    2. Minimize/hide the window
    3. Keep it running forever in background
    4. Compulsive checking still happens, just via Alt+Tab instead of launcher

6. YouTube Music Wrapper

File: periodic_background/digital_wellbeing/youtube-music-wrapper.sh

Current Behavior:

  • Checks if focus apps (VSCode, games, etc.) are running
  • Blocks YouTube Music launch if focus app detected

REQUESTED ENHANCEMENT:

  • When Steam is open → Block ALL browsers, close any open browsers
  • When browsers open → Block Steam, close Steam if running
  • This creates mutual exclusion between gaming and browsing