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

USE_PROCD=1
START=25

extra_command "uciadd" "Add default bridge configuration to network and firewall uci config"
extra_command "ucidel" "Delete default bridge configuration from network and 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}"
}

boot() {
	uciadd
	rc_procd start_service
}

uciupdate() {
	local net="${1}"

	uci_quiet get network.docker || {
		logger -t "dockerd-init" -p warn "No network uci config section for docker default bridge (docker0) found"
		return
	}

	[ -z "${net}" ] && {
		logger -t "dockerd-init" -p notice "Removing network uci config options for docker default bridge (docker0)"
		uci_quiet delete network.docker.netmask
		uci_quiet delete network.docker.ipaddr
		uci_quiet commit network
		return
	}

	eval "$(ipcalc.sh "${net}")"
	logger -t "dockerd-init" -p notice "Updating network uci config option \"${net}\" for docker default bridge (docker0)"
	uci_quiet set network.docker.netmask="${NETMASK}"
	uci_quiet set network.docker.ipaddr="${IP}"
	uci_quiet commit network
}

uciadd() {
	/etc/init.d/dockerd running && {
		echo "Please stop dockerd service first"
		exit 0
	}

	# Add network interface
	if ! uci_quiet get network.docker; then
		logger -t "dockerd-init" -p notice "Adding docker default interface to network uci config (docker)"
		uci_quiet add network interface
		uci_quiet rename network.@interface[-1]="docker"
		uci_quiet set network.docker.ifname="docker0"
		uci_quiet set network.docker.proto="static"
		uci_quiet set network.docker.auto="0"
		uci_quiet commit network
	fi

	# Add docker bridge device
	if ! uci_quiet get network.docker0; then
		logger -t "dockerd-init" -p notice "Adding docker default bridge device to network uci config (docker0)"
		uci_quiet add network device
		uci_quiet rename network.@device[-1]="docker0"
		uci_quiet set network.docker0.type="bridge"
		uci_quiet set network.docker0.name="docker0"
		uci_quiet add_list network.docker0.ifname="docker0"
		uci_quiet commit network
	fi

	# Add firewall zone
	if ! uci_quiet get firewall.docker; then
		logger -t "dockerd-init" -p notice "Adding docker default firewall zone to firewall uci config (docker)"
		uci_quiet add firewall zone
		uci_quiet rename firewall.@zone[-1]="docker"
		uci_quiet set firewall.docker.network="docker"
		uci_quiet set firewall.docker.input="REJECT"
		uci_quiet set firewall.docker.output="ACCEPT"
		uci_quiet set firewall.docker.forward="REJECT"
		uci_quiet set firewall.docker.name="docker"
		uci_quiet commit firewall
	fi

	reload_config
}

ucidel() {
	/etc/init.d/dockerd running && {
		echo "Please stop dockerd service first"
		exit 0
	}

	logger -t "dockerd-init" -p notice "Deleting docker default bridge device from network uci config (docker0)"
	uci_quiet delete network.docker0
	uci_quiet commit network

	logger -t "dockerd-init" -p notice "Deleting docker default interface from network uci config (docker)"
	uci_quiet delete network.docker
	uci_quiet commit network

	logger -t "dockerd-init" -p notice "Deleting docker firewall zone from firewall uci config (docker)"
	uci_quiet delete firewall.docker
	uci_quiet commit firewall

	reload_config
}

process_config() {
	local alt_config_file data_root log_level 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_list_foreach firewall blocked_interfaces add_docker_firewall_rules

	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 bip globals bip ""

	. /usr/share/libubox/jshn.sh
	json_init
	json_add_string "data-root" "${data_root}"
	json_add_string "log-level" "${log_level}"
	[ -z "${bip}" ] || json_add_string "bip" "${bip}"
	json_add_array "registry-mirrors"
	config_list_foreach globals registry_mirrors json_add_array_string
	json_close_array
	json_add_array "hosts"
	config_list_foreach globals hosts json_add_array_string
	json_close_array

	json_dump > "${DOCKERD_CONF}"

	uciupdate "${bip}"
}

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() {
	process_config
	procd_send_signal dockerd
}

service_triggers() {
	procd_add_reload_trigger 'dockerd'
}

add_docker_firewall_rules() {
	. /lib/functions/network.sh
	local device interface="${1}"

	# Ignore errors as it might already be present
	iptables --table filter --new DOCKER-USER 2>/dev/null
	network_get_physdev device "${interface}"
	if ! iptables --table filter --check DOCKER-USER --in-interface "${device}" --out-interface docker0 --jump DROP 2>/dev/null; then
		iptables --table filter --insert DOCKER-USER --in-interface "${device}" --out-interface docker0 --jump DROP
	fi
}

ip4tables_remove_nat() {
	iptables --table nat --delete OUTPUT ! --destination 127.0.0.0/8 --match addrtype --dst-type LOCAL --jump DOCKER
	iptables --table nat --delete PREROUTING --match addrtype --dst-type LOCAL --jump DOCKER

	iptables --table nat --flush DOCKER
	iptables --table nat --delete-chain DOCKER
}

ip4tables_remove_filter() {
	iptables --table filter --delete FORWARD --jump DOCKER-USER
	iptables --table filter --delete FORWARD --jump DOCKER-ISOLATION-STAGE-1
	iptables --table filter --delete FORWARD --out-interface docker0 --jump DOCKER
	iptables --table filter --delete FORWARD --out-interface docker0 --match conntrack --ctstate RELATED,ESTABLISHED --jump ACCEPT
	iptables --table filter --delete FORWARD --in-interface docker0 --out-interface docker0 --jump ACCEPT
	iptables --table filter --delete FORWARD --in-interface docker0 ! --out-interface docker0 --jump ACCEPT

	iptables --table filter --flush DOCKER
	iptables --table filter --flush DOCKER-ISOLATION-STAGE-1
	iptables --table filter --flush DOCKER-ISOLATION-STAGE-2
	iptables --table filter --flush DOCKER-USER

	iptables --table filter --delete-chain DOCKER
	iptables --table filter --delete-chain DOCKER-ISOLATION-STAGE-1
	iptables --table filter --delete-chain DOCKER-ISOLATION-STAGE-2
	iptables --table filter --delete-chain DOCKER-USER
}

ip4tables_remove() {
	ip4tables_remove_nat
	ip4tables_remove_filter
}

stop_service() {
	if /etc/init.d/dockerd running; then
		service_stop "/usr/bin/dockerd"
		ip4tables_remove
	fi
}