Ensure Scheduler Configuration File Permissions Are Restrictive

#!/usr/bin/env bash
#
# Automation: Fix permissions for /etc/kubernetes/scheduler.conf
# Scope: Run on every control plane node
# Idempotent: Safe to re-run; only adjusts permissions if needed.

set -euo pipefail

SCHED_CONF="/etc/kubernetes/scheduler.conf"
DESIRED_MODE="644"

echo "=== Checking for ${SCHED_CONF} ==="
if [ ! -e "${SCHED_CONF}" ]; then
  echo "File not found: ${SCHED_CONF} (nothing to do on this node)"
  exit 0
fi

# Get current permissions (numeric, e.g. 640, 644, 600)
CURRENT_MODE="$(stat -c '%a' "${SCHED_CONF}")"
echo "Current permissions: ${CURRENT_MODE}"

# Compare and only change if more permissive than desired
# Any mode numerically greater than 644 is considered more permissive here
if [ "${CURRENT_MODE}" != "${DESIRED_MODE}" ]; then
  echo "Setting permissions to ${DESIRED_MODE} on ${SCHED_CONF}"
  chmod "${DESIRED_MODE}" "${SCHED_CONF}"
else
  echo "Permissions already set to ${DESIRED_MODE}; no change needed"
fi

echo "=== Verifying remediation ==="
/bin/sh -c 'if test -e /etc/kubernetes/scheduler.conf; then stat -c permissions=%a /etc/kubernetes/scheduler.conf; fi'