#!/bin/bash
# LGSM check_permissions.sh
# Author: Daniel Gibbs
# Contributor: UltimateByte
# Website: https://gameservermanagers.com
# Description: Checks ownership & permissions of scripts, files and directories.

local commandname="CHECK"
local function_selfname="$(basename $(readlink -f "${BASH_SOURCE[0]}"))"

fn_check_ownership(){
	if [ -f "${rootdir}/${selfname}" ]; then
		if [ $(find "${rootdir}/${selfname}" -not -user $(whoami)|wc -l) -ne "0" ]; then
			selfownissue=1
		fi
	fi
	if [ -d "${functionsdir}" ]; then
		if [ $(find "${functionsdir}" -not -user $(whoami)|wc -l) -ne "0" ]; then
			funcownissue=1
		fi
	fi
	if [ -d "${filesdir}" ]; then
		if [ $(find "${filesdir}" -not -user $(whoami)|wc -l) -ne "0" ]; then
			filesownissue=1
		fi
	fi
	if [ "${selfownissue}" == "1" ]||[ "${funcownissue}" == "1" ]||[ "${filesownissue}" == "1" ]; then
		fn_print_fail_nl "Ownership issues found"
		fn_script_log_fatal "Ownership issues found"
		fn_print_information_nl "The current user ($(whoami)) does not have ownership of the following files:"
		fn_script_log_info "The current user ($(whoami)) does not have ownership of the following files:"
		{
			echo -e "User\tGroup\tFile\n"
			if [ "${selfownissue}" == "1" ]; then
				find "${rootdir}/${selfname}" -not -user $(whoami) -printf "%u\t\t%g\t%p\n"
			fi
			if [ "${funcownissue}" == "1" ]; then
				find "${functionsdir}" -not -user $(whoami) -printf "%u\t\t%g\t%p\n"
			fi
			if [ "${filesownissue}" == "1"  ]; then
				find "${filesdir}" -not -user $(whoami) -printf "%u\t\t%g\t%p\n"
			fi

		} | column -s $'\t' -t | tee -a "${scriptlog}"
		echo ""
		fn_print_information_nl "For more information, please see https://github.com/GameServerManagers/LinuxGSM/wiki/FAQ#-fail--starting-game-server-ownership-issues-found"
		fn_script_log "For more information, please see https://github.com/GameServerManagers/LinuxGSM/wiki/FAQ#-fail--starting-game-server-ownership-issues-found"
		core_exit.sh
	fi
}

fn_check_permissions(){
	if [ -d "${functionsdir}" ]; then
		if [ $(find "${functionsdir}" -type f -not -executable|wc -l) -ne "0" ]; then
			fn_print_fail_nl "Permissions issues found"
			fn_script_log_fatal "Permissions issues found"
			fn_print_information_nl "The following files are not executable:"
			fn_script_log_info "The following files are not executable:"
			{
				echo -e "File\n"
				find "${functionsdir}" -type f -not -executable -printf "%p\n"
			} | column -s $'\t' -t | tee -a "${scriptlog}"
			core_exit.sh
		fi
	fi

	# Check rootdir permissions
	if [ -n "${rootdir}" ]; then
		# Get permission numbers on directory under the form 775
		rootdirperm="$(stat -c %a "${rootdir}")"
		# Grab the first and second digit for user and group permission
		userrootdirperm="${rootdirperm:0:1}"
		grouprootdirperm="${rootdirperm:1:1}"
		if [ "${userrootdirperm}" != "7" ] && [ "${grouprootdirperm}" != "7" ]; then
			fn_print_fail_nl "Permissions issues found"
			fn_script_log_fatal "Permissions issues found"
			fn_print_information_nl "The following directory does not have the correct permissions:"
			fn_script_log_info "The following directory does not have the correct permissions:"
			fn_script_log_info "${rootdir}"
			ls -l "${rootdir}"
			core_exit.sh
		fi
	fi
	# Check if executable is executable and attempt to fix it
	# First get executable name
	execname="$(basename "${executable}")"
	if [ -f "${executabledir}/${execname}" ]; then
		# Get permission numbers on file under the form 775
		execperm="$(stat -c %a "${executabledir}/${execname}")"
		# Grab the first and second digit for user and group permission
		userexecperm="${execperm:0:1}"
		groupexecperm="${execperm:1:1}"
		# Check for invalid user permission
		if [ "${userexecperm}" == "0" ] || [ "${userexecperm}" == "2" ] || [ "${userexecperm}" == "4" ]  || [ "${userexecperm}" == "6" ]; then
			# If user permission is invalid, then check for invalid group permissions
			if [ "${groupexecperm}" == "0" ] || [ "${groupexecperm}" == "2" ] || [ "${groupexecperm}" == "4" ]  || [ "${groupexecperm}" == "6" ]; then
				# If permission issues are found
				fn_print_warn_nl "Permissions issue found"
				fn_script_log_warn "Permissions issue found"
				fn_print_information_nl "The following file is not executable:"
				ls -l "${executabledir}/${execname}"
				fn_script_log_info "The following file is not executable:"
				fn_script_log_info "${executabledir}/${execname}"
				fn_print_information_nl "Applying chmod u+x,g+x ${executabledir}/${execname}"
				fn_script_log_info "Applying chmod u+x,g+x ${execperm}"
				# Make the executable executable
				chmod u+x,g+x "${executabledir}/${execname}"
				# Second check to see if it's been successfully applied
				# Get permission numbers on file under the form 775
				execperm="$(stat -c %a "${executabledir}/${execname}")"
				# Grab the first and second digit for user and group permission
				userexecperm="${execperm:0:1}"
				groupexecperm="${execperm:1:1}"
				if [ "${userexecperm}" == "0" ] || [ "${userexecperm}" == "2" ] || [ "${userexecperm}" == "4" ]  || [ "${userexecperm}" == "6" ]; then
					if [ "${groupexecperm}" == "0" ] || [ "${groupexecperm}" == "2" ] || [ "${groupexecperm}" == "4" ]  || [ "${groupexecperm}" == "6" ]; then
					# If errors are still found
					fn_print_fail_nl "The following file could not be set executable:"
					ls -l "${executabledir}/${execname}"
					fn_script_log_warn "The following file could not be set executable:"
					fn_script_log_info "${executabledir}/${execname}"
					core_exit.sh
					fi
				fi
			fi
		fi
	fi
}

## The following fn_sys_perm_* functions checks for permission errors in /sys directory

# Checks for permission errors in /sys directory
fn_sys_perm_errors_detect(){
	# Reset test variables
	sysdirpermerror="0"
	classdirpermerror="0"
	netdirpermerror="0"
	# Check permissions
	# /sys, /sys/class and /sys/class/net should be readable & executable
	if [ ! -r "/sys" ]||[ ! -x "/sys" ]; then
		sysdirpermerror="1"
	fi
	if [ ! -r "/sys/class" ]||[ ! -x "/sys/class" ]; then
		classdirpermerror="1"
	fi
	if [ ! -r "/sys/class/net" ]||[ ! -x "/sys/class/net" ]; then
		netdirpermerror="1"
	fi
}

# Display a message on how to fix the issue manually
fn_sys_perm_fix_manually_msg(){
	echo ""
	fn_print_information_nl "To fix this issue, run this command as root:"
	fn_script_log_info "To fix this issue, run this command as root:"
	echo " * chmod a+rx /sys /sys/class /sys/class/net"
	fn_script_log "chmod a+rx /sys /sys/class /sys/class/net"
	sleep 1
	core_exit.sh
}

# Attempt to fix /sys related permission errors if sudo is available, exits otherwise
fn_sys_perm_errors_fix(){
	sudo -v > /dev/null 2>&1
	if [ $? -eq 0 ]; then
		fn_print_information_nl "Automatically fixing permissions"
		sleep 1
		fn_script_log_info "Automatically fixing permissions."
		if [ "${sysdirpermerror}" == "1" ]; then
			sudo chmod a+rx "/sys"
		fi
		if [ "${classdirpermerror}" == "1" ]; then
			sudo chmod a+rx "/sys/class"
		fi
		if [ "${netdirpermerror}" == "1" ]; then
			sudo chmod a+rx "/sys/class/net"
		fi
		# Run check again to see if it's fixed
		fn_sys_perm_errors_detect
		if [ "${sysdirpermerror}" == "1" ]||[ "${classdirpermerror}" == "1" ]||[ "${netdirpermerror}" == "1" ]; then
			fn_print_error "Could not fix permissions"
			fn_script_log_error "Could not fix permissions."
			sleep 1
			# Show the user how to fix
			fn_sys_perm_fix_manually_msg
		else
			fn_print_ok "Automatically fixing permissions"
			sleep 1
		fi
	else
	# Show the user how to fix
	fn_sys_perm_fix_manually_msg
	fi
}

# Processes to the /sys related permission errors check & fix/info
fn_sys_perm_error_process(){
	fn_sys_perm_errors_detect
	# If any error was found
	if [ "${sysdirpermerror}" == "1" ]||[ "${classdirpermerror}" == "1" ]||[ "${netdirpermerror}" == "1" ]; then
		fn_print_warn_nl "Permission error(s) found:"
		fn_script_log_info "Permission error(s) found:"
		sleep 1
		if [ "${sysdirpermerror}" == "1" ]; then
			echo "		* /sys permissions are $(stat -c %a /sys) instead of expected 555"
			fn_script_log "/sys permissions are $(stat -c %a /sys) instead of expected 555"
		fi
		if [ "${classdirpermerror}" == "1" ]; then
			echo "		* /sys/class permissions are $(stat -c %a /sys/class) instead of expected 755"
			fn_script_log "/sys/class permissions are $(stat -c %a /sys/class) instead of expected 755"
		fi
		if [ "${netdirpermerror}" == "1" ]; then
			echo "		* /sys/class/net permissions are $(stat -c %a /sys/class/net) instead of expected 755"
			fn_script_log "/sys/class/net permissions are $(stat -c %a /sys/class/net) instead of expected 755"
		fi
		sleep 1
		fn_print_information_nl "This error causes servers to fail starting properly"
		fn_script_log_info "This error causes servers to fail starting properly."
		# Run the fix
		fn_sys_perm_errors_fix
	fi
}

# Run perm error detect & fix/alert functions on /sys directories

## Run checks
fn_check_ownership
fn_check_permissions
fn_sys_perm_error_process