zapret/install_easy.sh

#!/bin/sh

# automated script for easy installing zapret

EXEDIR="$(dirname "$0")"
EXEDIR="$(cd "$EXEDIR"; pwd)"
IPSET_DIR="$EXEDIR/ipset"
ZAPRET_CONFIG="$EXEDIR/config"
ZAPRET_BASE="$EXEDIR"

. "$ZAPRET_CONFIG"
. "$ZAPRET_BASE/common/base.sh"
. "$ZAPRET_BASE/common/elevate.sh"
. "$ZAPRET_BASE/common/fwtype.sh"
. "$ZAPRET_BASE/common/dialog.sh"
. "$ZAPRET_BASE/common/ipt.sh"
. "$ZAPRET_BASE/common/installer.sh"

# install target
ZAPRET_TARGET=/opt/zapret

GET_LIST="$IPSET_DIR/get_config.sh"

[ -n "$TPPORT" ] || TPPORT=988

MD5=md5sum
exists $MD5 || MD5=md5

sedi()
{
	# MacOS doesnt support -i without parameter. busybox doesnt support -i with parameter.
	# its not possible to put "sed -i ''" to a variable and then use it
	if [ "$SYSTEM" = "macos" ]; then
		sed -i '' "$@"
	else
		sed -i "$@"
	fi
}

random()
{
	# $1 - min, $2 - max
	local r rs
	if [ -c /dev/urandom ]; then
		read rs </dev/urandom
	else
		rs="$RANDOM$RANDOM$(date)"
	fi
	# shells use signed int64
	r=1$(echo $rs | $MD5 | sed 's/[^0-9]//g' | head -c 17)
	echo $(( ($r % ($2-$1+1)) + $1 ))
}

check_readonly_system()
{
	local RO
	echo \* checking readonly system
        case $SYSTEM in
		systemd)
			[ -w "$SYSTEMD_SYSTEM_DIR" ] || RO=1
			;;
		openrc)
			[ -w "$(dirname "$INIT_SCRIPT")" ] || RO=1
			;;
	esac
	[ -z "$RO" ] || {
		echo '!!! READONLY SYSTEM DETECTED !!!'
		echo '!!! WILL NOT BE ABLE TO CONFIGURE STARTUP !!!'
		echo '!!! MANUAL STARTUP CONFIGURATION IS REQUIRED !!!'
		ask_yes_no N "do you want to continue" || exitp 5
	}
}

check_bins()
{
	echo \* checking executables

	local arch=$(get_bin_arch)
	local make_target
	[ "$FORCE_BUILD" = "1" ] && {
		echo forced build mode
		if [ "$arch" = "my" ]; then
			echo already compiled
		else
			arch=""
		fi
	}
	if [ -n "$arch" ] ; then
		echo found architecture "\"$arch\""
	elif [ -f "$EXEDIR/Makefile" ] && exists make; then
		echo trying to compile
		[ "$SYSTEM" = "macos" ] && make_target=mac
		make -C "$EXEDIR" $make_target || {
			echo could not compile
			make -C "$EXEDIR" clean
			exitp 8
		}
		echo compiled
	else
		echo build tools not found
		exitp 8
	fi
}

call_install_bin()
{
	"$EXEDIR/install_bin.sh" $1
}
get_bin_arch()
{
	call_install_bin getarch
}

install_binaries()
{
	echo \* installing binaries

	call_install_bin || {
		echo compatible binaries not found
		exitp 8
	}
}

write_config_var()
{
	# $1 - mode var
	local M
	eval M="\$$1"

	if grep -q "^$1=\|^#$1=" "$ZAPRET_CONFIG"; then
		# replace / => \/
		#M=${M//\//\\\/}
		M=$(echo $M | sed 's/\//\\\//g')
		if [ -n "$M" ]; then
			if contains "$M" " "; then
				sedi -Ee "s/^#?$1=.*$/$1=\"$M\"/" "$ZAPRET_CONFIG"
			else
				sedi -Ee "s/^#?$1=.*$/$1=$M/" "$ZAPRET_CONFIG"
			fi
		else
			# write with comment at the beginning
			sedi -Ee "s/^#?$1=.*$/#$1=/" "$ZAPRET_CONFIG"
		fi
	else
		# var does not exist in config. add it
		if [ -n "$M" ]; then
			echo "$1=$M" >>"$ZAPRET_CONFIG"
		else
			echo "#$1=$M" >>"$ZAPRET_CONFIG"
		fi
	fi
}

select_mode_mode()
{
	local edited v vars MODES="tpws tpws-socks nfqws filter custom"
	[ "$SYSTEM" = "macos" ] && MODES="tpws tpws-socks filter custom"
	echo
	echo select MODE :
	ask_list MODE "$MODES" tpws && write_config_var MODE

	case $MODE in
		tpws)
			vars="TPWS_OPT"
			;;
		nfqws)
			vars="NFQWS_OPT_DESYNC NFQWS_OPT_DESYNC_HTTP NFQWS_OPT_DESYNC_HTTPS NFQWS_OPT_DESYNC_HTTP6 NFQWS_OPT_DESYNC_HTTPS6"
			;;
	esac
	[ -n "$vars" ] && {
		echo
		while [ 1=1 ]; do
			for var in $vars; do
				eval v="\$$var"
				echo $var=\"$v\"
			done
			ask_yes_no N "do you want to edit the options" || {
				[ -n "$edited" ] && {
					for var in $vars; do
						write_config_var $var
					done
				}
				break
			}
			edit_vars $vars
			edited=1
			echo ..edited..
		done
	}
}
select_mode_http()
{
	[ "$MODE" != "filter" ] && [ "$MODE" != "tpws-socks" ] && {
		echo
		ask_yes_no_var MODE_HTTP "enable http support"
		write_config_var MODE_HTTP
	}
}
select_mode_keepalive()
{
	[ "$MODE" = "nfqws" ] && [ "$MODE_HTTP" = "1" ] && {
		echo
		echo enable keep alive support only if DPI checks every outgoing packet for http signature
		echo dont enable otherwise because it consumes more cpu resources
		ask_yes_no_var MODE_HTTP_KEEPALIVE "enable http keep alive support"
		write_config_var MODE_HTTP_KEEPALIVE
	}
}
select_mode_https()
{
	[ "$MODE" != "filter" ] && [ "$MODE" != "tpws-socks" ] && {
		echo
		ask_yes_no_var MODE_HTTPS "enable https support"
		write_config_var MODE_HTTPS
	}
}
select_mode_filter()
{
	local filter="none ipset hostlist"
	[ "$MODE" = "tpws-socks" ] && filter="none hostlist"
	echo
	echo select filtering :
	ask_list MODE_FILTER "$filter" none && write_config_var MODE_FILTER
}
select_mode()
{
	select_mode_mode
	select_mode_iface
	select_mode_http
	select_mode_keepalive
	select_mode_https
	select_mode_filter
}

select_getlist()
{
	if [ "$MODE_FILTER" = "ipset" -o "$MODE_FILTER" = "hostlist" ]; then
		local D=N
		[ -n "$GETLIST" ] && D=Y
		echo
		if ask_yes_no $D "do you want to auto download ip/host list"; then
			if [ "$MODE_FILTER" = "hostlist" ] ; then
				local GL_OLD=$GETLIST
				GETLIST="get_reestr_hostlist.sh"
				[ "$GL_OLD" != "$GET_LIST" ] && write_config_var GETLIST
			else
				GETLISTS="get_user.sh get_antifilter_ip.sh get_antifilter_ipsmart.sh get_antifilter_ipsum.sh get_reestr_ip.sh get_reestr_combined.sh get_reestr_resolve.sh"
				GETLIST_DEF="get_antifilter_ipsmart.sh"
				ask_list GETLIST "$GETLISTS" "$GETLIST_DEF" && write_config_var GETLIST
			fi
			return
		fi
	fi
	GETLIST=""
	write_config_var GETLIST
}
select_ipv6()
{
	local T=N

	[ "$DISABLE_IPV6" != '1' ] && T=Y
	local old6=$DISABLE_IPV6
	echo
	if ask_yes_no $T "enable ipv6 support"; then
		DISABLE_IPV6=0
	else
		DISABLE_IPV6=1
	fi
	[ "$old6" != "$DISABLE_IPV6" ] && write_config_var DISABLE_IPV6
}
select_fwtype()
{
	echo
	[ $(get_ram_mb) -le 400 ] && {
		echo WARNING ! you are running a low RAM system
		echo WARNING ! nft requires lots of RAM to load huge ip sets, much more than ipsets require
		echo WARNING ! if you need large lists it may be necessary to fall back to iptables+ipset firewall
	}
	echo select firewall type :
	ask_list FWTYPE "iptables nftables" "$FWTYPE" && write_config_var FWTYPE
}

ask_config()
{
	select_mode
	select_getlist
}

ask_config_offload()
{
	[ "$FWTYPE" = nftables ] || is_ipt_flow_offload_avail && {
		echo
		echo flow offloading can greatly increase speed on slow devices and high speed links \(usually 150+ mbits\)
		echo unfortuantely its not compatible with most nfqws options. nfqws traffic must be exempted from flow offloading.
		echo donttouch = disable system flow offloading setting if nfqws mode was selected, dont touch it otherwise and dont configure selective flow offloading
		echo none = always disable system flow offloading setting and dont configure selective flow offloading
		echo software = always disable system flow offloading setting and configure selective software flow offloading
		echo hardware = always disable system flow offloading setting and configure selective hardware flow offloading
		echo select flow offloading :
		ask_list FLOWOFFLOAD "donttouch none software hardware" donttouch && write_config_var FLOWOFFLOAD
	}
}

ask_config_tmpdir()
{
	# ask tmpdir change for low ram systems with enough free disk space
	[ -n "$GETLIST" ] && [ $(get_free_space_mb "$EXEDIR/tmp") -ge 128 ] && [ $(get_ram_mb) -le 400 ] && {
		echo
		echo /tmp in openwrt is tmpfs. on low RAM systems there may be not enough RAM to store downloaded files
		echo default tmpfs has size of 50% RAM
		echo "RAM  : $(get_ram_mb) Mb"
		echo "DISK : $(get_free_space_mb) Mb"
		echo select temp file location 
		[ -z "$TMPDIR" ] && TMPDIR=/tmp
		ask_list TMPDIR "/tmp $EXEDIR/tmp" && {
		    [ "$TMPDIR" = "/tmp" ] && TMPDIR=
		    write_config_var TMPDIR
		}
	}
}

ask_iface()
{
	# $1 - var to ask
	# $2 - additional name for empty string synonim

	local ifs i0 def new
	eval def="\$$1"

	[ -n "$2" ] && i0="$2 "
	case $SYSTEM in
		macos)
			ifs="$(ifconfig -l)"
			;;
		*)
			ifs="$(ls /sys/class/net)"
			;;
	esac
	[ -z "$def" ] && eval $1="$2"
	ask_list $1 "$i0$ifs" && {
		eval new="\$$1"
		[ "$new" = "$2" ] && eval $1=""
		write_config_var $1
	}
}
ask_iface_lan()
{
	echo LAN interface :
	ask_iface IFACE_LAN "NONE"
}
ask_iface_wan()
{
	echo WAN interface :
	ask_iface IFACE_WAN "ANY"
}

select_mode_iface()
{
	# openwrt has its own interface management scheme
	# filter just creates ip tables, no daemons involved
	# nfqws sits in POSTROUTING chain and unable to filter by incoming interface
	# tpws redirection works in PREROUTING chain
	# in tpws-socks mode IFACE_LAN specifies additional bind interface for the socks listener
	# it's not possible to instruct tpws to route outgoing connection to an interface (OS routing table decides)
	# custom mode can also benefit from interface names (depends on custom script code)

	if [ "$SYSTEM" = "openwrt" ] || [ "$MODE" = "filter" ]; then return; fi

	echo
	
	case "$MODE" in
		tpws-socks)
			echo "select LAN interface to allow socks access from your LAN. select NONE for localhost only."
			echo "expect socks on tcp port $TPPORT"
			ask_iface_lan
			;;
		tpws)
			echo "select LAN interface to operate in router mode. select NONE for local outgoing traffic only."
			if [ "$SYSTEM" = "macos" ]; then
				echo "WARNING ! OS feature \"internet sharing\" is not supported."
				echo "Only manually configured PF router is supported."
			else
				echo "WARNING ! This installer will not configure routing, NAT, ... for you. Its your responsibility."
			fi
			ask_iface_lan
			;;
		custom)
			echo "select LAN interface for your custom script (how it works depends on your code)"
			ask_iface_lan
			;;
	esac

	case "$MODE" in
		tpws)
			echo "select WAN interface for $MODE operations. select ANY to operate on any interface."
			[ -n "$IFACE_LAN" ] && echo "WAN filtering works only for local outgoing traffic !"
			ask_iface_wan
			;;
		nfqws)
			echo "select WAN interface for $MODE operations. select ANY to operate on any interface."
			ask_iface_wan
			;;
		custom)
			echo "select WAN interface for your custom script (how it works depends on your code)"
			ask_iface_wan
			;;
	esac
}

copy_all()
{
	cp -R "$1" "$2"
	[ -d "$2/tmp" ] || mkdir "$2/tmp"
}
copy_openwrt()
{
	local ARCH=$(get_bin_arch)
	local BINDIR="$1/binaries/$ARCH"
	
	[ -d "$2" ] || mkdir -p "$2"
	
	mkdir "$2/tpws" "$2/nfq" "$2/ip2net" "$2/mdig" "$2/binaries" "$2/binaries/$ARCH" "$2/init.d" "$2/tmp"
	cp -R "$1/common" "$1/ipset" "$2"
	cp -R "$1/init.d/openwrt" "$2/init.d"
	cp "$1/config" "$1/install_easy.sh" "$1/uninstall_easy.sh" "$1/install_bin.sh" "$1/blockcheck.sh" "$2"
	cp "$BINDIR/tpws" "$BINDIR/nfqws" "$BINDIR/ip2net" "$BINDIR/mdig" "$2/binaries/$ARCH"
}

_backup_settings()
{
	local i=0
	for f in "$@"; do
		[ -f "$ZAPRET_TARGET/$f" ] && cp -f "$ZAPRET_TARGET/$f" "/tmp/zapret-bkp-$i"
		i=$(($i+1))
	done
}
_restore_settings()
{
	local i=0
	for f in "$@"; do
		[ -f "/tmp/zapret-bkp-$i" ] && mv -f "/tmp/zapret-bkp-$i" "$ZAPRET_TARGET/$f" || rm -f "/tmp/zapret-bkp-$i"
		i=$(($i+1))
	done
}
backup_restore_settings()
{
	# $1 - 1 - backup, 0 - restore
	local mode=$1
	on_off_function _backup_settings _restore_settings $mode "config" "init.d/sysv/custom" "init.d/openwrt/custom" "init.d/macos/custom" "ipset/zapret-hosts-user.txt" "ipset/zapret-hosts-user-exclude.txt" "ipset/zapret-hosts-user-ipban.txt"
}

check_location()
{
	# $1 - copy function

	echo \* checking location

	# use inodes in case something is linked
	[ -d "$ZAPRET_TARGET" ] && [ $(get_dir_inode "$EXEDIR") = $(get_dir_inode "$ZAPRET_TARGET") ] || {
		echo
		echo easy install is supported only from default location : $ZAPRET_TARGET
		echo currently its run from $EXEDIR
		if ask_yes_no N "do you want the installer to copy it for you"; then
			local keep=N
			if [ -d "$ZAPRET_TARGET" ]; then
				echo
				echo installer found existing $ZAPRET_TARGET
				echo directory needs to be replaced. config and custom scripts can be kept or replaced with clean version
				if ask_yes_no N "do you want to delete all files there and copy this version"; then
					echo
					ask_yes_no Y "keep config, custom scripts and user lists" && keep=Y
					[ "$keep" = "Y" ] && backup_restore_settings 1
					rm -r "$ZAPRET_TARGET"
				else
					echo refused to overwrite $ZAPRET_TARGET. exiting
					exitp 3
				fi
			fi
			local B=$(dirname "$ZAPRET_TARGET")
			[ -d "$B" ] || mkdir -p "$B"
			$1 "$EXEDIR" "$ZAPRET_TARGET"
			[ "$keep" = "Y" ] && backup_restore_settings 0
			echo relaunching itself from $ZAPRET_TARGET
			exec $ZAPRET_TARGET/$(basename $0)
		else
			echo copying aborted. exiting
			exitp 3
		fi
	}
	echo running from $EXEDIR
}


check_prerequisites_linux()
{
	echo \* checking prerequisites

	local s cmd PKGS UTILS req="curl curl"
	case "$FWTYPE" in
		iptables)
			req="$req iptables iptables ip6tables iptables ipset ipset"
			;;
		nftables)
			req="$req nft nftables"
			;;
	esac

	PKGS=$(for s in $req; do echo $s; done |
		while read cmd; do
			read pkg
			exists $cmd || echo $pkg
		done | sort -u | xargs)
	UTILS=$(for s in $req; do echo $s; done |
		while read cmd; do
			read pkg
			echo $cmd
		done | sort -u | xargs)

	if [ -z "$PKGS" ] ; then
		echo required utilities exist : $UTILS
	else
		echo \* installing prerequisites

		echo packages required : $PKGS

		APTGET=$(whichq apt-get)
		YUM=$(whichq yum)
		PACMAN=$(whichq pacman)
		ZYPPER=$(whichq zypper)
		EOPKG=$(whichq eopkg)
		APK=$(whichq apk)
		if [ -x "$APTGET" ] ; then
			"$APTGET" update
			"$APTGET" install -y --no-install-recommends $PKGS dnsutils || {
				echo could not install prerequisites
				exitp 6
			}
		elif [ -x "$YUM" ] ; then
			"$YUM" -y install $PKGS || {
				echo could not install prerequisites
				exitp 6
			}
		elif [ -x "$PACMAN" ] ; then
			"$PACMAN" -Syy
			"$PACMAN" --noconfirm -S $PKGS || {
				echo could not install prerequisites
				exitp 6
			}
		elif [ -x "$ZYPPER" ] ; then
			"$ZYPPER" --non-interactive install $PKGS || {
				echo could not install prerequisites
				exitp 6
			}
		elif [ -x "$EOPKG" ] ; then
			"$EOPKG" -y install $PKGS || {
				echo could not install prerequisites
				exitp 6
			}
		elif [ -x "$APK" ] ; then
			"$APK" update
			# for alpine
			[ "$FWTYPE" = iptables ] && [ -n "$($APK list ip6tables)" ] && PKGS="$PKGS ip6tables"
			"$APK" add $PKGS || {
				echo could not install prerequisites
				exitp 6
			}
		else
			echo supported package manager not found
			echo you must manually install : $UTILS
			exitp 5
		fi
	fi
}


service_install_systemd()
{
	echo \* installing zapret service

	if [ -w "$SYSTEMD_SYSTEM_DIR" ] ; then
		rm -f "$INIT_SCRIPT"
		ln -fs "$EXEDIR/init.d/systemd/zapret.service" "$SYSTEMD_SYSTEM_DIR"
		"$SYSTEMCTL" daemon-reload
		"$SYSTEMCTL" enable zapret || {
			echo could not enable systemd service
			exitp 20
		}
	else
		echo '!!! READONLY SYSTEM DETECTED !!! CANNOT INSTALL SYSTEMD UNITS !!!'
	fi
}

timer_install_systemd()
{
	echo \* installing zapret-list-update timer

	if [ -w "$SYSTEMD_SYSTEM_DIR" ] ; then
		"$SYSTEMCTL" disable zapret-list-update.timer
		"$SYSTEMCTL" stop zapret-list-update.timer
		ln -fs "$EXEDIR/init.d/systemd/zapret-list-update.service" "$SYSTEMD_SYSTEM_DIR"
		ln -fs "$EXEDIR/init.d/systemd/zapret-list-update.timer" "$SYSTEMD_SYSTEM_DIR"
		"$SYSTEMCTL" daemon-reload
		"$SYSTEMCTL" enable zapret-list-update.timer || {
			echo could not enable zapret-list-update.timer
			exitp 20
		}
		"$SYSTEMCTL" start zapret-list-update.timer || {
			echo could not start zapret-list-update.timer
			exitp 30
		}
	else
		echo '!!! READONLY SYSTEM DETECTED !!! CANNOT INSTALL SYSTEMD UNITS !!!'
	fi
}

download_list()
{
	[ -x "$GET_LIST" ] &&	{
		echo \* downloading blocked ip/host list

		# can be txt or txt.gz
		"$IPSET_DIR/clear_lists.sh"
		"$GET_LIST" || {
			echo could not download ip list
			exitp 25
		}
	}
}


dnstest()
{
	# $1 - dns server. empty for system resolver
	nslookup w3.org $1 >/dev/null 2>/dev/null
}
check_dns()
{
	echo \* checking DNS

	dnstest || {
		echo -- DNS is not working. It's either misconfigured or blocked or you don't have inet access.
		return 1
	}
	echo system DNS is working
	return 0
}

install_systemd()
{
	INIT_SCRIPT_SRC="$EXEDIR/init.d/sysv/zapret"

	check_bins
	require_root
	check_readonly_system
	check_location copy_all
	check_dns
	service_stop_systemd
	select_fwtype
	check_prerequisites_linux
	install_binaries
	select_ipv6
	ask_config
	service_install_systemd
	download_list
	# in case its left from old version of zapret
	crontab_del_quiet
	# now we use systemd timers
	timer_install_systemd
	service_start_systemd
}

_install_sysv()
{
	# $1 - install init script

	check_bins
	require_root
	check_readonly_system
	check_location copy_all
	check_dns
	service_stop_sysv
	select_fwtype
	check_prerequisites_linux
	install_binaries
	select_ipv6
	ask_config
	$1
	download_list
	crontab_del_quiet
	# desktop system. more likely up at daytime
	crontab_add 10 22
	service_start_sysv
}

install_sysv()
{
	INIT_SCRIPT_SRC="$EXEDIR/init.d/sysv/zapret"
	_install_sysv install_sysv_init
}

install_openrc()
{
	INIT_SCRIPT_SRC="$EXEDIR/init.d/openrc/zapret"
	_install_sysv install_openrc_init
}


install_linux()
{
	INIT_SCRIPT_SRC="$EXEDIR/init.d/sysv/zapret"

	check_bins
	require_root
	check_location copy_all
	check_dns
	select_fwtype
	check_prerequisites_linux
	install_binaries
	select_ipv6
	ask_config
	download_list
	crontab_del_quiet
	# desktop system. more likely up at daytime
	crontab_add 10 22
	
	echo
	echo '!!! WARNING. YOUR SETUP IS INCOMPLETE !!!'
	echo you must manually add to auto start : $INIT_SCRIPT_SRC start
	echo make sure it\'s executed after your custom/firewall iptables configuration
	echo "if your system uses sysv init : ln -fs $INIT_SCRIPT_SRC /etc/init.d/zapret ; chkconfig zapret on"
}


check_prerequisites_openwrt()
{
	echo \* checking prerequisites

	local PKGS="curl" PKGS UPD=0

	case "$FWTYPE" in
		iptables)
			PKGS="$PKGS ipset iptables-mod-extra iptables-mod-nfqueue iptables-mod-filter iptables-mod-ipopt iptables-mod-conntrack-extra"
			[ "$DISABLE_IPV6" != "1" ] && PKGS="$PKGS ip6tables-mod-nat ip6tables-extra"
			;;
		nftables)
			PKGS="$PKGS nftables kmod-nft-nat kmod-nft-offload kmod-nft-queue"
			[ "$DISABLE_IPV6" != "1" ] && PKGS="$PKGS kmod-nft-nat6"
			;;
	esac

	if check_packages_openwrt $PKGS ; then
		echo everything is present
	else
		echo \* installing prerequisites

		opkg update
		UPD=1
		opkg install $PKGS || {
			echo could not install prerequisites
			exitp 6
		}
	fi
	
	is_linked_to_busybox gzip && {
		echo
		echo your system uses default busybox gzip. its several times slower than GNU gzip.
		echo ip/host list scripts will run much faster with GNU gzip
		echo installer can install GNU gzip but it requires about 100 Kb space
		if ask_yes_no N "do you want to install GNU gzip"; then
			[ "$UPD" = "0" ] && {
				opkg update
				UPD=1
			}
			opkg install --force-overwrite gzip
		fi
	}
	is_linked_to_busybox sort && {
		echo
		echo your system uses default busybox sort. its much slower and consumes much more RAM than GNU sort
		echo ip/host list scripts will run much faster with GNU sort
		echo installer can install GNU sort but it requires about 100 Kb space
		if ask_yes_no N "do you want to install GNU sort"; then
			[ "$UPD" = "0" ] && {
				opkg update
				UPD=1
			}
			opkg install --force-overwrite coreutils-sort
		fi
	}
	is_linked_to_busybox grep && {
		echo
		echo your system uses default busybox grep. its damn infinite slow with -f option
		echo get_combined.sh will be severely impacted
		echo installer can install GNU grep but it requires about 0.5 Mb space
		if ask_yes_no N "do you want to install GNU grep"; then
			[ "$UPD" = "0" ] && {
				opkg update
				UPD=1
			}
			opkg install --force-overwrite grep

			# someone reported device partially fail if /bin/grep is absent
			# grep package deletes /bin/grep
			[ -f /bin/grep ] || ln -s busybox /bin/grep
		fi
	}
}

deoffload_openwrt_firewall()
{
	echo \* checking flow offloading

	[ "$FWTYPE" = "nftables" ] || is_ipt_flow_offload_avail || {
		echo unavailable
		return
	}

	local fo=$(uci -q get firewall.@defaults[0].flow_offloading)

	if [ "$fo" = "1" ] ; then
		local mod=0
		printf "system wide flow offloading detected. "
		case $FLOWOFFLOAD in
			donttouch)
				if [ "$MODE" = "nfqws" ]; then
					echo its incompatible with nfqws tcp data tampering. disabling
					uci set firewall.@defaults[0].flow_offloading=0
					mod=1
				else
					if [ "$MODE" = "custom" ] ; then
						echo custom mode selected !!! only you can decide whether flow offloading is compatible
					else
						echo its compatible with selected options. not disabling
					fi
				fi
			;;
		*)
			echo zapret will disable system wide offloading setting and add selective rules if required
			uci set firewall.@defaults[0].flow_offloading=0
			mod=1
		esac
		[ "$mod" = "1" ] && uci commit firewall
	else
		echo system wide software flow offloading disabled. ok
	fi
			
}



install_openwrt()
{
	INIT_SCRIPT_SRC="$EXEDIR/init.d/openwrt/zapret"
	FW_SCRIPT_SRC="$EXEDIR/init.d/openwrt/firewall.zapret"
	OPENWRT_FW_INCLUDE=/etc/firewall.zapret
	OPENWRT_IFACE_HOOK="$EXEDIR/init.d/openwrt/90-zapret"
	
	check_bins
	require_root
	check_location copy_openwrt
	install_binaries
	check_dns

	echo \* stopping current firewall rules/daemons
	"$INIT_SCRIPT_SRC" stop_fw
	"$INIT_SCRIPT_SRC" stop_daemons

	select_fwtype
	select_ipv6
	check_prerequisites_openwrt
	ask_config
	ask_config_tmpdir
	ask_config_offload
	# stop and reinstall sysv init
	install_sysv_init
	remove_openwrt_firewall
	# free some RAM
	clear_ipset
	download_list
	crontab_del_quiet
	# router system : works 24/7. night is the best time
	crontab_add 0 6
	cron_ensure_running
	install_openwrt_iface_hook
	# in case of nftables or iptables without fw3 sysv init script also controls firewall
	[ -n "$OPENWRT_FW3" -a "$FWTYPE" = iptables ] && install_openwrt_firewall
	service_start_sysv
	deoffload_openwrt_firewall
	restart_openwrt_firewall
}



remove_pf_zapret_hooks()
{
	echo \* removing zapret PF hooks

	pf_anchors_clear
}

macos_fw_reload_trigger_clear()
{
	case "$MODE" in
		tpws|tpws-socks|custom)
			LISTS_RELOAD=
			write_config_var LISTS_RELOAD
			;;
	esac
}
macos_fw_reload_trigger_set()
{
	case "$MODE" in
		tpws|custom)
			LISTS_RELOAD="$INIT_SCRIPT_SRC reload-fw-tables"
			write_config_var LISTS_RELOAD
			;;
	esac
}

install_macos()
{
	INIT_SCRIPT_SRC="$EXEDIR/init.d/macos/zapret"

	# compile before root
	check_bins
	require_root
	check_location copy_all
	service_stop_macos
	remove_pf_zapret_hooks
	install_binaries
	check_dns
	select_ipv6
	ask_config
	service_install_macos
	macos_fw_reload_trigger_clear
	# gzip lists are incompatible with PF
	GZIP_LISTS=0 write_config_var GZIP_LISTS
	download_list
	macos_fw_reload_trigger_set
	crontab_del_quiet
	# desktop system. more likely up at daytime
	crontab_add 10 22
	service_start_macos
}


# build binaries, do not use precompiled
[ "$1" = "make" ] && FORCE_BUILD=1

check_system

[ "$SYSTEM" = "macos" ] && . "$EXEDIR/init.d/macos/functions"

case $SYSTEM in
	systemd)
		install_systemd
		;;
	openrc)
		install_openrc
		;;
	linux)
		install_linux
		;;
	openwrt)
		install_openwrt
		;;
	macos)
		install_macos
		;;
esac


exitp 0