diff --git a/hosts/guard/install_pacman_hooks.sh b/hosts/guard/install_pacman_hooks.sh index 63e92e7..c4b63c5 100755 --- a/hosts/guard/install_pacman_hooks.sh +++ b/hosts/guard/install_pacman_hooks.sh @@ -9,8 +9,21 @@ HOOKS_DIR="/etc/pacman.d/hooks" install -d -m 755 "$HOOKS_DIR" -# Ensure any legacy pre-transaction hook is removed so pre-unlock only occurs via the wrapper -rm -f "$HOOKS_DIR/10-unlock-etc-hosts.hook" 2>/dev/null || true +# Pre-transaction hook +cat >"$HOOKS_DIR/10-unlock-etc-hosts.hook" <<'HOOK' +[Trigger] +Operation = Upgrade +Operation = Install +Operation = Remove +Type = Package +Target = * + +[Action] +Description = Temporarily unlocking /etc/hosts for transaction +When = PreTransaction +Exec = /bin/bash /usr/local/share/hosts-guard/pacman-pre-unlock-hosts.sh +NeedsTargets +HOOK # Post-transaction hook cat >"$HOOKS_DIR/90-relock-etc-hosts.hook" <<'HOOK' @@ -30,9 +43,7 @@ HOOK # Place helper scripts into a shared location install -d -m 755 /usr/local/share/hosts-guard +install -m 755 "$SCRIPT_DIR/pacman-hooks/pacman-pre-unlock-hosts.sh" /usr/local/share/hosts-guard/ install -m 755 "$SCRIPT_DIR/pacman-hooks/pacman-post-relock-hosts.sh" /usr/local/share/hosts-guard/ -# Remove legacy pre-unlock helper if present to reduce accidental execution surface -rm -f /usr/local/share/hosts-guard/pacman-pre-unlock-hosts.sh 2>/dev/null || true - echo "Pacman hooks installed into $HOOKS_DIR." diff --git a/hosts/guard/pacman-hooks/pacman-post-relock-hosts.sh b/hosts/guard/pacman-hooks/pacman-post-relock-hosts.sh index 9589bb3..450f4e7 100644 --- a/hosts/guard/pacman-hooks/pacman-post-relock-hosts.sh +++ b/hosts/guard/pacman-hooks/pacman-post-relock-hosts.sh @@ -8,7 +8,7 @@ LOGTAG=hosts-guard-hook mount_layers_count() { awk '$5=="/etc/hosts"{c++} END{print c+0}' /proc/self/mountinfo 2>/dev/null || echo 0; } collapse_mounts() { local i=0 - if command -v mountpoint >/dev/null 2>&1; then + if command -v mountpoint >/devnull 2>&1; then while mountpoint -q "$TARGET"; do umount -l "$TARGET" >/dev/null 2>&1 || break i=$((i+1)) diff --git a/hosts/guard/pacman-hooks/pacman-pre-unlock-hosts.sh b/hosts/guard/pacman-hooks/pacman-pre-unlock-hosts.sh new file mode 100644 index 0000000..e44866a --- /dev/null +++ b/hosts/guard/pacman-hooks/pacman-pre-unlock-hosts.sh @@ -0,0 +1,66 @@ +#!/usr/bin/env bash +# Non-interactive pre-transaction hook to temporarily unlock /etc/hosts + +TARGET=/etc/hosts +LOGTAG=hosts-guard-hook + +stop_units_if_present() { + local units=(hosts-bind-mount.service hosts-guard.path) + for u in "${units[@]}"; do + if command -v systemctl >/dev/null 2>&1; then + if systemctl list-unit-files 2>/dev/null | grep -q "^$u"; then + systemctl stop "$u" >/dev/null 2>&1 || true + fi + fi + done +} + +is_ro_mount() { findmnt -no OPTIONS -T "$TARGET" 2>/dev/null | grep -qw ro; } +is_bind_mount() { findmnt -no OPTIONS -T "$TARGET" 2>/dev/null | grep -qw bind; } + +mount_layers_count() { awk '$5=="/etc/hosts"{c++} END{print c+0}' /proc/self/mountinfo 2>/dev/null || echo 0; } +cleanup_mount_stacks() { + local i=0 + # Unmount bind layers until /etc/hosts is no longer a mountpoint + if command -v mountpoint >/dev/null 2>&1; then + while mountpoint -q "$TARGET"; do + umount -l "$TARGET" >/dev/null 2>&1 || break + i=$((i+1)) + (( i > 20 )) && break + done + else + # Fallback to best-effort using mountinfo count + local cnt + cnt=$(mount_layers_count) + while (( cnt > 1 )); do + umount -l "$TARGET" >/dev/null 2>&1 || break + i=$((i+1)) + (( i > 20 )) && break + cnt=$(mount_layers_count) + done + fi +} + +# Drop protective attributes if present +if command -v lsattr >/dev/null 2>&1; then + attrs=$(lsattr -d "$TARGET" 2>/dev/null || true) + echo "$attrs" | grep -q " i " && chattr -i "$TARGET" >/dev/null 2>&1 || true + echo "$attrs" | grep -q " a " && chattr -a "$TARGET" >/dev/null 2>&1 || true +fi + +stop_units_if_present + +logger -t "$LOGTAG" "pre: unlocking /etc/hosts (starting)" +echo "$(date -Is) pre-unlock" >> /run/hosts-guard-hook.log 2>/dev/null || true + +# Always collapse any existing layers; we'll operate on the plain file +cleanup_mount_stacks + +# If someone managed a ro single-layer mount, ensure rw by remounting or collapsing again +if is_ro_mount; then + mount -o remount,rw "$TARGET" >/dev/null 2>&1 || cleanup_mount_stacks +fi + +logger -t "$LOGTAG" "pre: unlocking /etc/hosts (done)" + +exit 0