#!/bin/sh /etc/rc.common

USE_PROCD=1
START=99

extra_command "uciadd" "<ignored> <device> <zone> Add docker bridge configuration to firewall uci config"
extra_command "ucidel" "<ignored> <device> <zone> Delete docker bridge configuration from firewall uci config"

DOCKER_CONF_DIR="/tmp/dockerd"
DOCKERD_CONF="${DOCKER_CONF_DIR}/daemon.json"

uci_quiet() {
	uci -q "${@}" >/dev/null
}

json_add_array_string() {
	json_add_string "" "${1}"
}

uciadd() {
	local iface="${1}"
	local device="${2}"
	local zone="${3}"

	[ -z "${device}" ] && {
		device="docker0"
		zone="docker"
	}

	# Add firewall zone
	if ! uci_quiet get firewall.${zone}; then
		logger -t "dockerd-init" -p notice "Adding firewall zone '${zone}' to firewall config"
		uci_quiet add firewall zone
		uci_quiet rename firewall.@zone[-1]="${zone}"
		uci_quiet set firewall.@zone[-1].name="${zone}"
		uci_quiet set firewall.@zone[-1].input="ACCEPT"
		uci_quiet set firewall.@zone[-1].output="ACCEPT"
		uci_quiet set firewall.@zone[-1].forward="ACCEPT"
		uci_quiet commit firewall
	fi

	# Add device to firewall zone
	if uci_quiet get firewall.${zone}; then
		uci_quiet del_list firewall.${zone}.device="${device}"
		if [ docker0 = "$device" ]; then
			uci_quiet del_list firewall.${zone}.subnet="172.16.0.0/12"
			uci_quiet add_list firewall.${zone}.subnet="172.16.0.0/12"
		else
			uci_quiet add_list firewall.${zone}.device="${device}"
		fi
		uci_quiet commit firewall
	fi

	# Add forwarding rules
	local forwarding_section
	check_forwarding() {
		local cfg="${1}"
		local srcm="${2}"
		local destm="${3}"

		local src dest
		config_get src "${cfg}" src
		config_get dest "${cfg}" dest

		[[ "${src}" = "${srcm}" && "${dest}" = "${destm}" ]] \
			&& forwarding_section="${cfg}"
	}

	config_load firewall
	forwarding_section=""
	config_foreach check_forwarding forwarding ${zone} wan
	[[ -n "${forwarding_section}" ]] || {
		uci_quiet set firewall.${zone}_to_wan=forwarding
		uci_quiet set firewall.${zone}_to_wan.src=${zone}
		uci_quiet set firewall.${zone}_to_wan.dest=wan
	}

	forwarding_section=""
	config_foreach check_forwarding forwarding ${zone} lan
	[[ -n "${forwarding_section}" ]] || {
		uci_quiet set firewall.${zone}_to_lan=forwarding
		uci_quiet set firewall.${zone}_to_lan.src=${zone}
		uci_quiet set firewall.${zone}_to_lan.dest=lan
	}

	forwarding_section=""
	config_foreach check_forwarding forwarding lan ${zone}
	[[ -n "${forwarding_section}" ]] || {
		uci_quiet set firewall.lan_to_${zone}=forwarding
		uci_quiet set firewall.lan_to_${zone}.src=lan
		uci_quiet set firewall.lan_to_${zone}.dest=${zone}
	}
	uci_quiet commit firewall

	/etc/init.d/firewall reload
}

ucidel() {
	local iface="${1}"
	local device="${2}"
	local zone="${3}"

	[ -z "${device}" ] && {
		device="docker0"
		zone="docker"
	}

	# Remove interface from firewall zone
	if uci_quiet get firewall.${zone}; then
		logger -t "dockerd-init" -p notice "Deleting network device '${device}' in zone '${zone}' from firewall config"
		uci_quiet del_list firewall.${zone}.device="${device}"
		uci_quiet commit firewall
		# Remove Firewall zone if network is empty
		if ! uci_quiet get firewall.${zone}.device; then
			logger -t "dockerd-init" -p notice "Deleting firewall zone '${zone}' from firewall config"
			uci_quiet delete firewall.${zone}
			uci_quiet delete firewall.${zone}_to_wan
			uci_quiet delete firewall.${zone}_to_lan
			uci_quiet delete firewall.lan_to_${zone}
		fi
		uci_quiet commit firewall
	fi

	/etc/init.d/firewall reload
}

process_config() {
	local alt_config_file data_root log_level iptables ip6tables bip

	[ -f /etc/config/dockerd ] || {
		# Use the daemon default configuration
		DOCKERD_CONF=""
		return 0
	}

	# reset configuration
	rm -fr "${DOCKER_CONF_DIR}"
	mkdir -p "${DOCKER_CONF_DIR}"

	config_load 'dockerd'
	config_get alt_config_file globals alt_config_file
	[ -n "${alt_config_file}" ] && [ -f "${alt_config_file}" ] && {
		ln -s "${alt_config_file}" "${DOCKERD_CONF}"
		return 0
	}

	config_get data_root globals data_root "/opt/docker/"
	config_get log_level globals log_level "warn"
	config_get_bool iptables globals iptables "0"
	config_get_bool ip6tables globals ip6tables "0"

	# Don't add these options by default
	# omission == docker defaults
	config_get log_driver globals log_driver ""
	config_get bip globals bip ""
	config_get registry_mirrors globals registry_mirrors ""
	config_get hosts globals hosts ""
	config_get dns globals dns ""
	config_get_bool ipv6 globals ipv6 ""
	config_get ip globals ip ""
	config_get fixed_cidr globals fixed_cidr ""
	config_get fixed_cidr_v6 globals fixed_cidr_v6 ""
	# Use the *_proxy environment variable as the default value
	config_get http_proxy proxies http_proxy "${http_proxy}"
	config_get https_proxy proxies https_proxy "${https_proxy}"
	config_get no_proxy proxies no_proxy "${no_proxy}"
	config_get storage_driver globals storage_driver ""
	config_get max_concurrent_downloads globals max_concurrent_downloads ""

	. /usr/share/libubox/jshn.sh
	json_init
	json_add_string "data-root" "${data_root}"
	json_add_string "log-level" "${log_level}"
	json_add_boolean "iptables" "${iptables}"
	json_add_boolean "ip6tables" "${ip6tables}"
	[ -z "${log_driver}" ] || json_add_string "log-driver" "${log_driver}"
	[ -z "${bip}" ] || json_add_string "bip" "${bip}"
	[ -z "${registry_mirrors}" ] || json_add_array "registry-mirrors"
	[ -z "${registry_mirrors}" ] || config_list_foreach globals registry_mirrors json_add_array_string
	[ -z "${registry_mirrors}" ] || json_close_array
	[ -z "${hosts}" ] || json_add_array "hosts"
	[ -z "${hosts}" ] || config_list_foreach globals hosts json_add_array_string
	[ -z "${hosts}" ] || json_close_array
	[ -z "${dns}" ] || json_add_array "dns"
	[ -z "${dns}" ] || config_list_foreach globals dns json_add_array_string
	[ -z "${dns}" ] || json_close_array
	[ -z "${ipv6}" ] || json_add_boolean "ipv6" "${ipv6}"
	[ -z "${ip}" ] || json_add_string "ip" "${ip}"
	[ -z "${fixed_cidr}" ] || json_add_string "fixed-cidr" "${fixed_cidr}"
	[ -z "${fixed_cidr_v6}" ] || json_add_string "fixed-cidr-v6" "${fixed_cidr_v6}"
	if [ -n "${http_proxy}" ] || [ -n "${https_proxy}" ] || [ -n "${no_proxy}" ]; then
		json_add_object "proxies"
		[ -z "${http_proxy}" ] || json_add_string "http-proxy" "${http_proxy}"
		[ -z "${https_proxy}" ] || json_add_string "https-proxy" "${https_proxy}"
		[ -z "${no_proxy}" ] || json_add_string "no-proxy" "${no_proxy}"
		json_close_object
	fi
	[ -z "${storage_driver}" ] || json_add_string "storage-driver" "${storage_driver}"

	[ "${max_concurrent_downloads:-0}" -eq "0" ] || json_add_int "max-concurrent-downloads" "${max_concurrent_downloads}"
	json_add_string "log-driver" "json-file"
	json_add_object "log-opts"
	json_add_string "max-size" "50m"
	json_add_string "max-file" "2"
	json_close_object

	json_dump > "${DOCKERD_CONF}"

	[ "${iptables}" -eq "1" ] && config_foreach iptables_add_blocking_rule firewall
}

start_service() {
	local nofile=$(cat /proc/sys/fs/nr_open)

	process_config

	procd_open_instance
	procd_set_param stderr 1
	if [ -z "${DOCKERD_CONF}" ]; then
		procd_set_param command /usr/bin/dockerd
	else
		procd_set_param command /usr/bin/dockerd --config-file="${DOCKERD_CONF}"
	fi
	procd_set_param limits nofile="${nofile} ${nofile}"
	procd_close_instance
}

reload_service() {
	if [ -f "${DOCKERD_CONF}" -a -f /etc/config/dockerd ]; then
		local oldroot=`jsonfilter -i "${DOCKERD_CONF}" -e @[\"data-root\"]`
		local newroot=`uci get dockerd.globals.data_root`
		if [ "$oldroot" != "$newroot" ]; then
			restart
			return 0
		fi
	fi
	process_config
	procd_send_signal dockerd
}

service_triggers() {
	procd_add_reload_trigger 'dockerd'
}

iptables_add_blocking_rule() {
	local cfg="${1}"

	local device=""
	local extra_iptables_args=""

	handle_iptables_rule() {
		local interface="${1}"
		local outbound="${2}"
		local extra_iptables_args="${3}"

		local inbound=""

		. /lib/functions/network.sh
		network_get_physdev inbound "${interface}"

		[ -z "${inbound}" ] && {
			logger -t "dockerd-init" -p notice "Unable to get physical device for interface ${interface}"
			return
		}

		# Wait for a maximum of 10 second per command, retrying every millisecond
		local iptables_wait_args="--wait 10 --wait-interval 1000"

		# Ignore errors as it might already be present
		iptables ${iptables_wait_args} --table filter --new DOCKER-USER 2>/dev/null
		if ! iptables ${iptables_wait_args} --table filter --check DOCKER-USER --in-interface "${inbound}" --out-interface "${outbound}" ${extra_iptables_args} --jump REJECT 2>/dev/null; then
			logger -t "dockerd-init" -p notice "Drop traffic from ${inbound} to ${outbound}"
			iptables ${iptables_wait_args} --table filter --insert DOCKER-USER --in-interface "${inbound}" --out-interface "${outbound}" ${extra_iptables_args} --jump REJECT
		fi
	}

	config_get device "${cfg}" device

	[ -z "${device}" ] && {
		logger -t "dockerd-init" -p notice "No device configured for ${cfg}"
		return
	}

	config_get extra_iptables_args "${cfg}" extra_iptables_args
	config_list_foreach "${cfg}" blocked_interfaces handle_iptables_rule "${device}" "${extra_iptables_args}"
}

stop_service() {
	if /etc/init.d/dockerd running; then
		service_stop "/usr/bin/dockerd"
	fi
}