ssh-monitor/ssh-monitor-perms.sh

#!/bin/bash
# Path permission helpers for ssh-monitor, sac-client, watchdog, updater.
# shellcheck shell=bash

ssh_monitor_config_peek() {
	local key="$1" file="$2" default="${3:-}"
	local line val
	[ -f "$file" ] || {
		printf '%s\n' "$default"
		return 0
	}
	line="$(grep -E "^[[:space:]]*${key}=" "$file" 2>/dev/null | tail -1)" || {
		printf '%s\n' "$default"
		return 0
	}
	val="${line#*=}"
	val="${val#"${val%%[![:space:]]*}"}"
	val="${val%"${val##*[![:space:]]}"}"
	val="${val#\"}"
	val="${val%\"}"
	val="${val#\'}"
	val="${val%\'}"
	printf '%s\n' "$val"
}

ssh_monitor_truthy() {
	case "${1,,}" in
	1 | yes | true | on) return 0 ;;
	esac
	return 1
}

ssh_monitor_path_mode() {
	local path="$1"
	[ -e "$path" ] || return 1
	stat -c '%a' "$path" 2>/dev/null || stat -f '%OLp' "$path" 2>/dev/null
}

ssh_monitor_path_owner() {
	local path="$1"
	[ -e "$path" ] || return 1
	stat -c '%U:%G' "$path" 2>/dev/null
}

ssh_monitor_is_root_owned() {
	local path="$1" own
	[ -e "$path" ] || return 0
	own="$(ssh_monitor_path_owner "$path" 2>/dev/null || true)"
	[ "$own" = "root:root" ]
}

ssh_monitor_secure_dir() {
	local dir="$1"
	[ -n "$dir" ] || return 1
	mkdir -p "$dir" 2>/dev/null || return 1
	chmod 700 "$dir" 2>/dev/null || true
	chown root:root "$dir" 2>/dev/null || true
}

ssh_monitor_secure_file() {
	local file="$1"
	local dir
	[ -n "$file" ] || return 1
	dir="$(dirname "$file")"
	ssh_monitor_secure_dir "$dir" || true
	if [ ! -f "$file" ]; then
		: >"$file" 2>/dev/null || touch "$file" 2>/dev/null || return 1
	fi
	chmod 600 "$file" 2>/dev/null || true
	chown root:root "$file" 2>/dev/null || true
}

# Существующий файл или каталог: 600/700 root:root; для отсутствующего пути — только родительский каталог.
ssh_monitor_harden_path() {
	local path="$1"
	[ -n "$path" ] || return 0
	if [ -d "$path" ]; then
		ssh_monitor_secure_dir "$path"
	elif [ -f "$path" ] || [ -L "$path" ]; then
		ssh_monitor_secure_file "$path"
	else
		local parent
		parent="$(dirname "$path")"
		[ -n "$parent" ] && [ "$parent" != "." ] && ssh_monitor_secure_dir "$parent"
	fi
}

ssh_monitor_warn_path_perms() {
	local path="$1" kind="$2" max_mode="${3:-600}"
	local mode own msg
	[ -e "$path" ] || return 0
	if ! ssh_monitor_is_root_owned "$path"; then
		own="$(ssh_monitor_path_owner "$path" 2>/dev/null || echo '?')"
		msg="WARN: ${kind} ${path}: владелец ${own}, ожидается root:root"
		printf '%s\n' "$msg" >&2
		[ -n "${write_log:-}" ] && write_log "$msg" || true
	fi
	mode="$(ssh_monitor_path_mode "$path" 2>/dev/null || echo "")"
	if [ -n "$mode" ] && [ "$((10#$mode))" -gt "$((10#$max_mode))" ]; then
		msg="WARN: ${kind} ${path}: mode ${mode}, рекомендуется не шире ${max_mode}"
		printf '%s\n' "$msg" >&2
		[ -n "${write_log:-}" ] && write_log "$msg" || true
	fi
}

ssh_monitor_check_config_file_perms() {
	local file="${1:-/etc/ssh-monitor.conf}"
	local strict="${2:-0}"
	local mode msg
	[ -f "$file" ] || return 0
	if ! ssh_monitor_is_root_owned "$file"; then
		msg="WARN: конфиг ${file}: владелец $(ssh_monitor_path_owner "$file" 2>/dev/null || echo '?'), ожидается root:root"
		printf '%s\n' "$msg" >&2
		[ -n "${write_log:-}" ] && write_log "$msg" || true
		if ssh_monitor_truthy "$strict"; then
			printf '%s\n' "CONFIG_STRICT_PERMS=1: исправьте владельца конфига (chown root:root ${file})" >&2
			return 1
		fi
	fi
	mode="$(ssh_monitor_path_mode "$file" 2>/dev/null || echo "")"
	case "$mode" in
	600 | 400) ;;
	*)
		msg="WARN: конфиг ${file}: mode ${mode:-?}, рекомендуется 600 или 400 (chmod 600 ${file})"
		printf '%s\n' "$msg" >&2
		[ -n "${write_log:-}" ] && write_log "$msg" || true
		if ssh_monitor_truthy "$strict"; then
			printf '%s\n' "CONFIG_STRICT_PERMS=1: ослабленные права конфига недопустимы" >&2
			return 1
		fi
		;;
	esac
	return 0
}