port: ethernet: Allow setting duplex mode

[people/ms/network.git] / src / functions / functions.device

#!/bin/bash
###############################################################################
#                                                                             #
# IPFire.org - A linux based firewall                                         #
# Copyright (C) 2010  Michael Tremer & Christian Schmidt                      #
#                                                                             #
# This program is free software: you can redistribute it and/or modify        #
# it under the terms of the GNU General Public License as published by        #
# the Free Software Foundation, either version 3 of the License, or           #
# (at your option) any later version.                                         #
#                                                                             #
# This program is distributed in the hope that it will be useful,             #
# but WITHOUT ANY WARRANTY; without even the implied warranty of              #
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the               #
# GNU General Public License for more details.                                #
#                                                                             #
# You should have received a copy of the GNU General Public License           #
# along with this program.  If not, see <http://www.gnu.org/licenses/>.       #
#                                                                             #
###############################################################################

device_list() {
	local devices

	# Add all interfaces
	local device
	for device in $(list_directory ${SYS_CLASS_NET}); do
		list_append_one devices "${device}"
	done

	# Add all PHYs
	list_append devices $(phy_list)

	# Add all serial devices
	list_append devices $(serial_list)

	# Return a sorted result
	list_sort ${devices}
}

# Check if the device exists
device_exists() {
	local device=${1}

	# If device name was not found, exit.
	[ -n "${device}" ] || return ${EXIT_ERROR}

	# Check for a normal network device.
	[ -d "${SYS_CLASS_NET}/${device}" ] && return ${EXIT_OK}

	# If the check above did not find a result,
	# we check for PHYs.
	phy_exists "${device}" && return ${EXIT_OK}

	# If the check above did not find a result,
	# we check for serial devices.
	serial_exists ${device}
}

device_matches_pattern() {
	local device="${1}"
	assert isset device

	local pattern="${2}"
	assert isset pattern

	pattern="^${pattern//N/[[:digit:]]+}$"

	[[ ${device} =~ ${pattern} ]] \
		&& return ${EXIT_TRUE} || return ${EXIT_FALSE}
}

device_delete() {
	local device=${1}
	assert isset device

	# Nothing to do, it device does not exist.
	device_exists ${device} || return ${EXIT_OK}

	# Shut down device before we delete it
	device_set_down "${device}"

	# Delete the device.
	cmd_quiet ip link delete ${device}
	local ret=$?

	if [ ${ret} -ne ${EXIT_OK} ]; then
		log ERROR "device: Could not delete device '${device}': ${ret}"
		return ${EXIT_ERROR}
	fi

	return ${ret}
}

device_has_flag() {
	local device=${1}
	local flag=${2}

	local flags=$(__device_get_file ${device} flags)

	if [[ "$(( ${flags} & ${flag} ))" -eq 0 ]]; then
		return ${EXIT_FALSE}
	else
		return ${EXIT_TRUE}
	fi
}

# Check if the device is up
device_is_up() {
	local device=${1}

	device_exists ${device} || return ${EXIT_ERROR}

	device_has_flag ${device} 0x1
}

device_ifindex_to_name() {
	local idx=${1}
	assert isset idx

	local device device_idx
	for device in $(list_directory "${SYS_CLASS_NET}"); do
		device_idx=$(device_get_ifindex ${device})

		if [ "${device_idx}" = "${idx}" ]; then
			print "${device}"
			return ${EXIT_OK}
		fi
	done

	return ${EXIT_ERROR}
}

device_get_ifindex() {
	local device=${1}
	assert isset device

	local path="${SYS_CLASS_NET}/${1}/ifindex"

	# Check if file can be read.
	[ -r "${path}" ] || return ${EXIT_ERROR}

	print "$(<${path})"
}

# Check if the device is a bonding device
device_is_bonding() {
	[ -d "/sys/class/net/${1}/bonding" ]
}

# Check if the device bonded in a bonding device
device_is_bonded() {
	local device=${1}

	[ -d "${SYS_CLASS_NET}/${device}/bonding_slave" ]
}

# Check if the device is a bridge
device_is_bridge() {
	[ -d "/sys/class/net/${1}/bridge" ]
}

device_is_bridge_attached() {
	local device=${1}
	[ -d "${SYS_CLASS_NET}/${device}/brport" ]
}

device_is_wireless_monitor() {
	local device="${1}"
	assert isset device

	device_is_wireless "${device}" && \
		device_matches_pattern "${device}" "${PORT_PATTERN_WIRELESS_MONITOR}"
}

device_is_wireless_adhoc() {
	local device="${1}"
	assert isset device

	device_is_wireless "${device}" && \
		device_matches_pattern "${device}" "${PORT_PATTERN_WIRELESS_ADHOC}"
}

device_get_bridge() {
	local device=${1}
	assert isset device

	# Check if device is attached to a bridge.
	device_is_bridge_attached ${device} || return ${EXIT_ERROR}

	local ifindex_path="${SYS_CLASS_NET}/${device}/brport/bridge/ifindex"
	[ -r "${ifindex_path}" ] || return ${EXIT_ERROR}

	local ifindex=$(<${ifindex_path})
	assert isset ifindex

	device_ifindex_to_name ${ifindex}
}

# Check if the device is a vlan device
device_is_vlan() {
	local device=${1}
	assert isset device

	[ -e "${PROC_NET_VLAN}/${device}" ]
}

# Check if the device has vlan devices
device_has_vlans() {
	local device=${1}
	assert isset device

	if device_is_vlan ${device}; then
		return ${EXIT_FALSE}
	fi

	local vlans=$(device_get_vlans ${device})
	[ -n "${vlans}" ] && return ${EXIT_OK} || return ${EXIT_ERROR}
}

device_get_vlans() {
	local device=${1}
	assert isset device

	# If no 8021q module has been loaded into the kernel,
	# we cannot do anything.
	[ -r "${PROC_NET_VLAN_CONFIG}" ] || return ${EXIT_OK}

	local dev spacer1 id spacer2 parent
	while read dev spacer1 id spacer2 parent; do
		[ "${parent}" = "${device}" ] || continue

		print "${dev}"
	done < ${PROC_NET_VLAN_CONFIG}
}

# Check if the device is a ppp device
device_is_ppp() {
	local device=${1}

	local type=$(__device_get_file ${device} type)

	[ "${type}" = "512" ] && return ${EXIT_OK} || return ${EXIT_ERROR}
}

# Check if the device is a pointopoint device.
device_is_ptp() {
	local device=${1}

	device_has_flag ${device} 0x10
}

# Check if the device is a loopback device
device_is_loopback() {
	local device=${1}

	[ "${device}" = "lo" ]
}

# Check if the device is a dummy device
#  This is the worst possible check, but all I could come up with
device_is_dummy() {
	local device="${1}"

	[[ ${device} =~ ^dummy[0-9]+$ ]]
}

device_is_ipsec() {
	local device="${1}"

	[[ ${device} =~ ^ipsec\- ]]
}

# Check if the device is a wireless device
device_is_wireless() {
	local device=${1}

	[ -d "${SYS_CLASS_NET}/${device}/phy80211" ]
}

device_is_vti() {
	local device=${1}

	local type=$(__device_get_file ${device} type)

	[ "${type}" = "768" ] && return ${EXIT_OK} || return ${EXIT_ERROR}
}

device_is_vti6() {
	local device=${1}

	local type=$(__device_get_file ${device} type)

	[ "${type}" = "769" ] && return ${EXIT_OK} || return ${EXIT_ERROR}
}

device_get_phy() {
	local device="${1}"

	if device_is_wireless "${device}"; then
		print "$(<${SYS_CLASS_NET}/${device}/phy80211/name)"
		return ${EXIT_OK}
	fi

	return ${EXIT_ERROR}
}

device_is_phy() {
	phy_exists "$@"
}

device_is_serial() {
	serial_exists "$@"
}

# Returns true if a device is a tun device
device_is_tun() {
	local device="${1}"

	[ -e "${SYS_CLASS_NET}/${device}/tun_flags" ]
}

# Check if the device is a physical network interface
device_is_ethernet() {
	local device=${1}

	device_is_ethernet_compatible "${device}" || \
		return ${EXIT_ERROR}

	device_is_loopback ${device} && \
		return ${EXIT_ERROR}

	device_is_bonding ${device} &&  \
		return ${EXIT_ERROR}

	device_is_bridge ${device} && \
		return ${EXIT_ERROR}

	device_is_ppp ${device} && \
		return ${EXIT_ERROR}

	device_is_vlan ${device} && \
		return ${EXIT_ERROR}

	device_is_dummy ${device} && \
		return ${EXIT_ERROR}

	device_is_tun ${device} && \
		return ${EXIT_ERROR}

	return ${EXIT_OK}
}

# Get the device type
device_get_type() {
	local device=${1}

	# If the device does not exist (happens on udev remove events),
	# we do not bother to run all checks.
	if ! device_exists "${device}"; then
		echo "unknown"

	elif device_is_vlan ${device}; then
		echo "vlan"

	elif device_is_bonding ${device}; then
		echo "bonding"

	elif device_is_bridge ${device}; then
		echo "bridge"

	elif device_is_ppp ${device}; then
		echo "ppp"

	elif device_is_loopback ${device}; then
		echo "loopback"

	elif device_is_wireless_adhoc ${device}; then
		echo "wireless-adhoc"

	elif device_is_wireless ${device}; then
		echo "wireless"

	elif device_is_dummy ${device}; then
		echo "dummy"

	elif device_is_tun ${device}; then
		echo "tun"

	elif device_is_ethernet ${device}; then
		echo "ethernet"

	elif device_is_serial ${device}; then
		echo "serial"

	elif device_is_phy ${device}; then
		echo "phy"

	else
		echo "$(device_tunnel_get_type "${device}")"
	fi
}

# This function just checks the types a ip-tunnel device usually have
# so when we know that the device is an ip-tunnel device we save time
device_tunnel_get_type() {
	local device=${1}

	# If the device does not exist (happens on udev remove events),
	# we do not bother to run all checks.
	if ! device_exists "${device}"; then
		echo "unknown"

	elif device_is_vti ${device}; then
		echo "vti"

	elif device_is_vti6 ${device}; then
		echo "vti6"

	else
		echo "unknown"
	fi
}

device_is_ethernet_compatible() {
	local device="${1}"

	# /sys/class/net/*/type must equal 1 for ethernet compatible devices
	local type="$(__device_get_file "${device}" "type")"
	[[ "${type}" = "1" ]]
}

device_get_status() {
	local device=${1}
	assert isset device

	local status=${STATUS_DOWN}

	if device_is_up ${device}; then
		status=${STATUS_UP}

		if ! device_has_carrier ${device}; then
			status=${STATUS_NOCARRIER}
		fi
	fi

	echo "${status}"
}

device_get_address() {
	local device=${1}

	cat ${SYS_CLASS_NET}/${device}/address 2>/dev/null
}

device_set_address() {
	assert [ $# -eq 2 ]

	local device="${1}"
	local addr="${2}"
	
	if ! device_exists "${device}"; then
		error "Device '${device}' does not exist."
		return ${EXIT_ERROR}
	fi

	# Do nothing if the address has not changed
	local old_addr="$(device_get_address "${device}")"
	if [ -n "${old_addr}" -a "${addr}" = "${old_addr}" ]; then
		return ${EXIT_OK}
	fi

	log DEBUG "Setting address of '${device}' from '${old_addr}' to '${addr}'"

	local up
	if device_is_up "${device}"; then
		device_set_down "${device}"
		up=1
	fi

	ip link set "${device}" address "${addr}"
	local ret=$?

	if [ "${up}" = "1" ]; then
		device_set_up "${device}"
	fi

	if [ "${ret}" != "0" ]; then
		error_log "Could not set address '${addr}' on device '${device}'"
	fi

	return ${ret}
}

device_get() {
	local device
	for device in $(list_directory "${SYS_CLASS_NET}"); do
		# bonding_masters is no device
		[ "${device}" = "bonding_masters" ] && continue

		echo "${device}"
	done

	return ${EXIT_OK}
}

# Check if a device has a cable plugged in
device_has_carrier() {
	local device=${1}
	assert isset device

	local carrier=$(__device_get_file ${device} carrier)
	[ "${carrier}" = "1" ]
}

device_is_promisc() {
	local device=${1}

	device_has_flag ${device} 0x200
}

device_set_promisc() {
	local device=${1}
	local state=${2}

	assert device_exists ${device}
	assert isset state
	assert isoneof state on off

	ip link set ${device} promisc ${state}
}

# Check if the device is free
device_is_free() {
	! device_is_used "$@"
}

# Check if the device is used
device_is_used() {
	local device=${1}

	device_has_vlans ${device} && \
		return ${EXIT_OK}
	device_is_bonded ${device} && \
		return ${EXIT_OK}
	device_is_bridge_attached ${device} && \
		return ${EXIT_OK}

	return ${EXIT_ERROR}
}

# Give the device a new name
device_set_name() {
	local source=$1
	local destination=${2}

	# Check if devices exists
	if ! device_exists ${source} || device_exists ${destination}; then
		return 4
	fi

	local up
	if device_is_up ${source}; then
		ip link set ${source} down
		up=1
	fi

	ip link set ${source} name ${destination}

	if [ "${up}" = "1" ]; then
		ip link set ${destination} up
	fi
}

device_set_master() {
	local device="${1}"
	assert isset device

	local master="${2}"
	assert isset master

	if ! cmd ip link set "${device}" master "${master}"; then
		log ERROR "Could not set master ${master} for device ${device}"
		return ${EXIT_ERROR}
	fi

	return ${EXIT_OK}
}

device_remove_master() {
	local device="${1}"
	assert isset device

	if ! cmd ip link set "${device}" nomaster; then
		log ERROR "Could not remove master for device ${device}"
		return ${EXIT_ERROR}
	fi

	return ${EXIT_OK}
}

# Set device up
device_set_up() {
	assert [ $# -eq 1 ]

	local device=${1}

	# Do nothing if device is already up
	device_is_up ${device} && return ${EXIT_OK}

	log INFO "Bringing up ${device}"

	device_set_parent_up ${device}
	if ! cmd ip link set ${device} up; then
		return ${EXIT_ERROR}
	fi

	# Set SMP affinity
	if interrupt_use_smp_affinity; then
		device_auto_configure_smp_affinity ${device}
	fi

	return ${EXIT_OK}
}

device_set_parent_up() {
	local device=${1}
	local parent

	if device_is_vlan ${device}; then
		parent=$(vlan_get_parent ${device})

		device_is_up ${parent} && return ${EXIT_OK}

		log DEBUG "Setting up parent device '${parent}' of '${device}'"

		device_set_up ${parent}
		return $?
	fi

	return ${EXIT_OK}
}

# Set device down
device_set_down() {
	assert [ $# -eq 1 ]

	local device=${1}
	local ret=${EXIT_OK}

	if device_is_up ${device}; then
		log INFO "Bringing down ${device}"

		cmd ip link set ${device} down
		ret=$?
	fi

	device_set_parent_down ${device}

	return ${ret}
}

device_set_parent_down() {
	local device=${1}
	local parent

	if device_is_vlan ${device}; then
		parent=$(vlan_get_parent ${device})

		device_is_up ${parent} || return ${EXIT_OK}

		if device_is_free ${parent}; then
			log DEBUG "Tearing down parent device '${parent}' of '${device}'"

			device_set_down ${parent}
		fi
	fi
	
	return ${EXIT_OK}
}

device_get_mtu() {
	local device=${1}

	# Return an error if the device does not exist
	device_exists ${device} || return ${EXIT_ERROR}

	echo $(<${SYS_CLASS_NET}/${device}/mtu)
}

# Set mtu to a device
device_set_mtu() {
	local device=${1}
	local mtu=${2}

	assert device_exists ${device}

	# Handle bridges differently
	if device_is_bridge ${device}; then
		local port
		for port in $(bridge_get_members ${device}); do
			device_set_mtu ${port} ${mtu}
		done
	fi

	log INFO "Setting MTU of ${device} to ${mtu}"

	local up
	if device_is_up ${device}; then
		device_set_down ${device}
		up=1
	fi

	local ret=${EXIT_OK}
	if ! cmd ip link set ${device} mtu ${mtu}; then
		ret=${EXIT_ERROR}

		log ERROR "Could not set MTU ${mtu} on ${device}"
	fi

	if [ "${up}" = "1" ]; then
		device_set_up ${device}
	fi

	return ${ret}
}

device_adjust_mtu() {
	assert [ $# -eq 2 ]

	local device="${1}"
	local other_device="${2}"

	local mtu="$(device_get_mtu "${other_device}")"
	device_set_mtu "${device}" "${mtu}"
}

device_discover() {
	local device=${1}

	log INFO "Running discovery process on device '${device}'."

	local hook
	for hook in $(hook_zone_get_all); do
		hook_zone_exec ${hook} discover ${device}
	done
}

device_identify() {
	assert [ $# -ge 1 ]

	local device="${1}"

	# Flash for ten seconds by default
	local seconds="10"

	# Run in background?
	local background="false"

	local arg
	while read arg; do
		case "${arg}" in
			--background)
				background="true"
				;;
			--seconds=*)
				seconds="$(cli_get_val "${arg}")"
				;;
		esac
	done <<< "$(args "$@")"

	assert isinteger seconds

	if ! device_exists "${device}"; then
		log ERROR "Cannot identify device ${device}: Does not exist"
		return ${EXIT_ERROR}
	fi

	if ! device_is_ethernet "${device}"; then
		log DEBUG "Cannot identify device ${device}: Not an ethernet device"
		return ${EXIT_NOT_SUPPORTED}
	fi

	log DEBUG "Identifying device ${device}"

	local command="ethtool --identify ${device} ${seconds}"
	local ret=0

	if enabled background; then
		cmd_background "${command}"
	else
		cmd_quiet "${command}"
		ret=$?
	fi

	return ${ret}
}

device_has_ip() {
	local device=${1}
	local addr=${2}

	assert isset addr
	assert device_exists ${device}

	# IPv6 addresses must be fully imploded
	local protocol=$(ip_detect_protocol ${addr})
	case "${protocol}" in
		ipv6)
			addr=$(ipv6_format "${addr}")
			;;
	esac

	list_match ${addr} $(device_get_addresses ${device})
}

device_get_addresses() {
	local device=${1}

	assert device_exists ${device}

	local prot
	local addr
	local line
	ip addr show ${device} | \
		while read prot addr line; do
			[ "${prot:0:4}" = "inet" ] && echo "${addr}"
		done
}

__device_get_file() {
	local device=${1}
	local file=${2}

	fread "${SYS_CLASS_NET}/${device}/${file}"
}

__device_set_file() {
	assert [ $# -eq 3 ]

	local device="${1}"
	local file="${2}"
	local value="${3}"

	fappend "${SYS_CLASS_NET}/${device}/${file}" "${value}"
}

device_get_rx_bytes() {
	local device=${1}

	__device_get_file ${device} statistics/rx_bytes
}

device_get_tx_bytes() {
	local device=${1}

	__device_get_file ${device} statistics/tx_bytes
}

device_get_rx_packets() {
	local device=${1}

	__device_get_file ${device} statistics/rx_packets
}

device_get_tx_packets() {
	local device=${1}

	__device_get_file ${device} statistics/tx_packets
}

device_get_rx_errors() {
	local device=${1}

	__device_get_file ${device} statistics/rx_errors
}

device_get_tx_errors() {
	local device=${1}

	__device_get_file ${device} statistics/tx_errors
}

device_get_speed() {
	local device=${1}

	local speed=$(__device_get_file ${device} speed)

	# Exit for no output (i.e. no link detected)
	isset speed || return ${EXIT_ERROR}

	# Don't return anything for negative values
	[ ${speed} -lt 0 ] && return ${EXIT_ERROR}

	print "${speed}"
}

device_set_speed() {
	local device="${1}"
	assert isset device

	local speed="${2}"
	assert isinteger speed

	if ! cmd_quiet ethtool --change "${device}" speed "${speed}"; then
		log ERROR "Could not set speed of ${device} to ${speed} MBit/s"
		return ${EXIT_ERROR}
	fi

	log DEBUG "Set speed of ${device} to ${speed} MBit/s"

	return ${EXIT_OK}
}

device_get_duplex() {
	local device=${1}

	local duplex=$(__device_get_file ${device} duplex)

	case "${duplex}" in
		unknown)
			return ${EXIT_ERROR}
			;;
		*)
			print "${duplex}"
			;;
	esac
}

device_set_duplex() {
	local device="${1}"
	assert isset device

	local duplex="${2}"
	assert isset duplex

	if ! cmd_quiet ethtool --change "${device}" duplex "${duplex}"; then
		log ERROR "Could not set ${device} to ${duplex}-duplex mode"
		return ${EXIT_ERROR}
	fi

	log DEBUG "Set ${device} to ${duplex}-duplex mode"
	return ${EXIT_OK}
}

device_get_link_string() {
	local device="${1}"
	assert isset device

	local s

	local speed="$(device_get_speed "${device}")"
	if isset speed; then
		list_append s "${speed} MBit/s"
	fi

	local duplex="$(device_get_duplex "${device}")"
	if isset duplex; then
		list_append s "${duplex} duplex"
	fi

	print "${s}"
}

device_auto_configure_smp_affinity() {
	assert [ $# -eq 1 ]

	local device=${1}

	if lock_acquire "smp-affinity" 60; then
		device_set_smp_affinity ${device} auto

		lock_release "smp-affinity"
	fi
}

device_set_smp_affinity() {
	assert [ $# -eq 2 ]

	local device=${1}
	local mode=${2}

	# mode can be auto which will automatically try to find
	# the least busy processor, or an integer for the desired
	# processor that should handle this device

	local num_processors=$(system_get_processors)

	if [ "${mode}" = "auto" ]; then
		local processor=$(interrupt_choose_least_busy_processor)
	else
		assert isinteger mode
		local processor=${mode}

		if [ ${processor} -gt ${num_processors} ]; then
			log ERROR "Processor ${processor} does not exist"
			return ${EXIT_ERROR}
		fi
	fi

	local interrupts=$(interrupts_for_device ${device})
	if ! isset interrupts; then
		log DEBUG "${device} has no interrupts. Not changing SMP affinity"
		return ${EXIT_OK}
	fi

	# Set SMP affinity
	local interrupt
	for interrupt in ${interrupts}; do
		interrupt_set_smp_affinity ${interrupt} ${processor}
	done

	# Find all queues and assign them to the next processor
	local queue
	for queue in $(device_get_queues ${device}); do
		case "${queue}" in
			# Only handle receive queues
			rx-*)
				for interrupt in $(interrupts_for_device_queue ${device} ${queue}); do
					interrupt_set_smp_affinity ${interrupt} ${processor}
				done

				device_queue_set_smp_affinity ${device} ${queue} ${processor}
				;;

			# Ignore the rest
			*)
				continue
				;;
		esac

		# Get the next available processor if in auto mode
		[ "${mode}" = "auto" ] && processor=$(system_get_next_processor ${processor})
	done

	return ${EXIT_OK}
}

device_get_queues() {
	assert [ $# -eq 1 ]

	local device=${1}

	list_directory "${SYS_CLASS_NET}/${device}/queues"
}

device_supports_multiqueue() {
	local device=${1}

	local num_queues=$(device_num_queues ${device})

	if isset num_queues && [ ${num_queues} -gt 2 ]; then
		return ${EXIT_TRUE}
	fi

	return ${EXIT_FALSE}
}

device_num_queues() {
	local device=${1}
	local type=${2}

	isset type && assert isoneof type rx tx

	local i=0

	local q
	for q in $(device_get_queues ${device}); do
		case "${type},${q}" in
			rx,rx-*)
				(( i++ ))
				;;
			tx,tx-*)
				(( i++ ))
				;;
			*,*)
				(( i++ ))
				;;
		esac
	done

	print ${i}
}

device_queue_get_smp_affinity() {
	assert [ $# -eq 2 ]

	local device=${1}
	local queue=${2}

	local path="${SYS_CLASS_NET}/${device}/queues/${queue}"

	case "${queue}" in
		rx-*)
			path="${path}/rps_cpus"
			;;
		tx-*)
			path="${path}/xps_cpus"
			;;
	esac
	assert [ -r "${path}" ]

	__bitmap_to_processor_ids $(<${path})
}

device_queue_set_smp_affinity() {
	assert [ $# -eq 3 ]

	local device=${1}
	local queue=${2}
	local processor=${3}

	local path="${SYS_CLASS_NET}/${device}/queues/${queue}/rps_cpus"
	assert [ -w "${path}" ]

	log DEBUG "Setting SMP affinity of ${device} (${queue}) to processor ${processor}"

	__processor_id_to_bitmap ${processor} > ${path}
}

# Tries to find a device which has the given IP address assigned
device_get_by_assigned_ip_address() {
	local ip=${1}

	assert isset ip

	local device

	# Read the first line of ip addr show to
	read -r device <<< $(ip addr show to "${ip}")

	# If we did not found a device we return with ${EXIT_ERROR}
	if ! isset device; then
		return ${EXIT_ERROR}
	fi

	# We get something like:
	# 3: upl0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
	# and we want upl0 so we take the second word and removing the :
	device=(${device})
	device=${device[1]}
	device=${device%:}

	print "${device}"
	return ${EXIT_OK}
}

device_get_by_mac_address() {
	local mac=${1}

	assert isset mac

	local device

	for device in $(device_list); do
		if [ "${mac}" = "$(device_get_address ${device})" ]; then
			print "${device}"
			return ${EXIT_OK}
		fi
	done

	# We could not found a port to the given mac address so we return exit error
	return ${EXIT_ERROR}
}