setup_hosts_guard.sh died partway on every run under `set -euo pipefail`,
which is why hosts-guard.path / hosts-bind-mount.service / nsswitch-guard.path
sat installed-but-disabled since 2026-02-02 and resolved-guard.path was never
installed at all — /etc/hosts had no watcher to restore it if tampered.
Two aborts, both silent:
1. `local_dot=$(grep -E '^\s*DNSOverTLS\s*=' ... | tail -1 | sed ...)` — grep
exits 1 when the key is absent, pipefail propagates, the assignment returns
1, set -e kills the script. DNSOverTLS is absent from a default
resolved.conf, so this fired on EVERY run, right before resolved-guard.path
was enabled. The fix-if-missing branch below it was unreachable because
detecting "missing" aborted first. Same trap on the ReadEtcHosts probe.
check_and_enable_services.sh already guarded its copy with `|| true`.
2. `systemctl restart systemd-resolved` — resolved is MASKED here (dnsmasq
serves DNS), so the restart failed and aborted the script on its last step,
after everything was already configured. Now skipped with a note.
Before: exit 1, resolved-guard disabled, nsswitch-guard start-limit-hit.
After: exit 0; hosts-guard.path, hosts-bind-mount.service, nsswitch-guard.path
and resolved-guard.path all enabled+active. DNS still resolves; getent ahosts
on doubleclick/googlesyndication/facebook returns 0.0.0.0; /etc/hosts still
immutable at 176888 lines.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01JsCs1GUyiinA7bg68YvAh1
Immutable git-tracked files break git tooling. The pre-push ci-mirror gate
runs `pre-commit run --all-files`; end-of-file-fixer opens every file rb+
and dies with "PermissionError: Operation not permitted", so no push from a
normal checkout could ever succeed — every push had to be routed through a
throwaway worktree (a fresh checkout gets new, non-immutable inodes). The
same immutability also breaks pre-commit's unstaged-changes stash: the
`git checkout -- .` unlink fails, the restore never runs, and unrelated
unstaged edits are silently reverted.
Enforcement does not depend on these sources being locked: /etc/hosts is
itself chattr +i, hosts-guard.path watches and re-enforces it via
enforce-hosts.sh against the locked-hosts canonical snapshot, and
hosts-bind-mount.service pins it. Editing the sources changes nothing until
install.sh is re-run as root, which regenerates the guarded artifacts.
Companion to 6e3d61d (same fix for setup_midnight_shutdown.sh).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01JsCs1GUyiinA7bg68YvAh1
Replaces the bespoke chattr/bind-mount/systemd-watcher implementations for
/etc/hosts and /etc/shutdown-schedule.conf with the new shared guard-lib
(~/guard-lib, guardctl), so screen-locker and steam-backlog-enforcer's new
block-gaming feature stop maintaining parallel copies of the same
tamper-resistance mechanism.
- pacman_wrapper.sh: pre/post hook fallbacks now call guard-lib's generic
unlock-all/relock-all scripts (covers every registered guard instance,
not just /etc/hosts)
- setup_midnight_shutdown.sh: installs/updates its guarded config via
guardctl file-guard instead of hand-rolled chattr + systemd unit
generation; the schedule ratchet logic (block-if-more-lenient) stays
bespoke since guardctl's generic unlock can't represent it
- new hosts/guard/plugins/nsswitch-plugin.sh, resolved-plugin.sh
Also fixes, at user's request even though pre-existing: 3 shellcheck
SC2329 false positives in pacman_wrapper.sh (functions invoked indirectly
by name, not actually dead) and 1 SC2001 style warning (echo|sed VM-name
extraction replaced with parameter expansion, verified equivalent output).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AFNiYQQgSLAkiBXswyimPq
- linux_configuration/tests: update script paths after periodic_background/
reorganisation (hosts_file_monitor, makepkg_capped, music_parallelism,
shutdown_timer_monitor, usage_monitoring_installer_efficiency)
- test_i3blocks_efficiency.sh: remove checks for HEARTBEAT_INTERVAL_S and
WARP_POLL_INTERVAL_S constants that no longer exist
- test_pacman_wrapper_security.sh: remove tests 20-21 (builtin time helpers /
external date calls) that are no longer applicable; update path
- generate_hosts_file.sh: add sed unblock rules for delio.com.pl and
loverslab.com to stay consistent with install.sh whitelist
- steam_backlog_enforcer/scanning.py: remove unplayable_reason arg from
logger.info call (too many format args); drop matching test assertion
- steam_backlog_enforcer/tests/test_protondb.py: add
test_unplayable_reason_no_trending_tier to restore 100% branch coverage
on protondb.py line 97 (was previously covered indirectly)
- Screen locker: disable VT switching (Ctrl+Alt+Fn) via setxkbmap
srvrkeys:none on startup; restore on close (production mode only).
Gracefully skips if setxkbmap is not installed (shutil.which).
Tests: 7 new tests, 100% branch coverage maintained.
- Midnight shutdown: restore real schedule values (Mon-Wed 21:00,
Thu-Sun 22:00, morning end 05:00); re-enable the three commented-out
leniency checks in check_schedule_protection(); self-lock script with
chattr +i at end of enable_midnight_shutdown().
- Hosts install: add UNBLOCK_STATE_FILE tracking for whitelisted domains;
check_unblock_entries_protection() blocks installation if the unblock
list grows; save state after install; self-lock install.sh and
generate_hosts_file.sh with chattr +i.
