iwd
iwd (iNet wireless daemon) is a wireless daemon for Linux written by Intel that aims to replace WPA supplicant. The core goal of the project is to optimize resource utilization by not depending on any external libraries and instead utilizing features provided by the Linux Kernel to the maximum extent possible. [1]
iwd can work in standalone mode or in combination with comprehensive network managers like ConnMan, systemd-networkd and NetworkManager.
Contents
Installation
Usage
The iwd package provides the client program iwctl
, the daemon iwd
and the Wi-Fi monitoring tool iwmon
.
Start/enable iwd.service
so it can be controlled using the iwctl
command.
iwctl
To get an interactive prompt do:
$ iwctl
The interactive prompt is then displayed with a prefix of [iwd]#
.
- In the
iwctl
prompt you can auto-complete commands and device names by hittingTab
. - You can use all commands as command line arguments without entering an interactive prompt. For example:
iwctl device wlp3s0 show
.
To list all available commands:
[iwd]# help
Connect to a network
First, if you do not know your wireless device name, list all wifi devices:
[iwd]# device list
Then, to scan for networks:
[iwd]# station device scan
You can then list all available networks:
[iwd]# station device get-networks
Finally, to connect to a network:
[iwd]# station device connect SSID
If a passphrase is required, you will be prompted to enter it.
-
iwd
automatically stores network passphrases in the/var/lib/iwd
directory and uses them to auto-connect in the future. See #Optional configuration. - To connect to a network with spaces in the SSID, the network name should be double quoted when connecting.
- iwd only supports PSK pass-phrases from 8 to 63 ASCII-encoded characters. The following error message will be given if the requirements are not met: "PMK generation failed. Ensure Crypto Engine is properly configured"
Disconnect from a network
To disconnect from a network:
[iwd]# station device disconnect
Show device information
To display the details of a WiFi device, like MAC address, state and connected network:
[iwd]# device device show
Manage known networks
To list networks you have connected to previously:
[iwd]# known-networks list
To forget a known network:
[iwd]# known-networks SSID forget
WPA Enterprise
EAP-PWD
For connecting to a EAP-PWD protected enterprice access point you need to create a file called: essid.8021x
in the folder /var/lib/iwd
with the following content:
/var/lib/iwd/essid.8021x
[Security] EAP-Method=PWD EAP-Identity=your_enterprise_email EAP-Password=your_password [Settings] Autoconnect=True
If you do not want autoconnect to the AP you can set the option to False and connect manually to the access point via iwctl
. The same applies to the password, if you do not want to store it plaintext leave the option out of the file and just connect to the enterprise AP.
EAP-PEAP
Like EAP-PWD, you also need to create a essid.8021x
in the folder. Before you proceed to write the configuration file, this is also a good time to find out which CA certificate your organization uses. This is an example configuration file that uses MSCHAPv2 password authentication:
/var/lib/iwd/essid.8021x
[Security] EAP-Method=PEAP EAP-Identity=anonymous@realm.edu EAP-PEAP-CACert=/path/to/root.crt EAP-PEAP-Phase2-Method=MSCHAPV2 EAP-PEAP-Phase2-Identity=johndoe@realm.edu EAP-PEAP-Phase2-Password=hunter2 [Settings] Autoconnect=true
Addtrust External CA Root
, as your institution probably issues certificates through Internet2's InCommon. However, you should always refer to your organization's help desk if in doubt.TLS Based EAP Methods on older kernels
Linux kernels older than v4.20 (e.g. linux-lts) have to be patched to connect to EAP-TLS, EAP-TTLS, and EAP-PEAP. Edit the PKGBUILD for the kernel and add the following sources
PKGBUILD
"iwd1.patch::https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/patch/?id=ab2a33c1c0b1b0a45c16746dd0101057c6d432ed" "iwd2.patch::https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/patch/?id=3a478ace6154e33009f9b01acbd4eaf7615fef0e" "iwd3.patch::https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/patch/?id=5faadff684460b7f4064f9f28db8915a56601147" "iwd4.patch::https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/patch/?id=3c7f3a6c70b47858a065b7a86313f390b083ee40" "iwd5.patch::https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/patch/?id=5362bbfdf2a8a5810d4237e4dbbf5da043e47fb6" "iwd6.patch::https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/patch/?id=5c93ce3acc010425eab01dc8e0ffb5529f3f85c1" "iwd7.patch::https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/patch/?id=ca4d545b92cf52ffe777cc7cfbaf64100dfa6e9c" "iwd8.patch::https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/patch/?id=f2ac228eaba9fe3f4fcf80b121eb92707afdd4de"
And add the following line to the end of the kernel config:
config
CONFIG_PKCS8_PRIVATE_KEY_PARSER=y
Then update the checksums of the PKGBUILD with updpkgsums
(from pacman-contrib):
$ updpkgsums
and build the package.
Other cases
More example tests can be found in the test cases of the upstream repository.
Optional configuration
File /etc/iwd/main.conf
can be used for main configuration.
By default, iwd
stores the network configuration in /var/lib/iwd
directory. The configuration file is named as network.type
where network is network SSID and type is network type i.e. one of "open", "wep", "psk", "8021x". The file is used to store the encrypted PreSharedKey
and optionally the cleartext Passphrase
and can be created by the user without invoking iwctl
. The file can also be used for other configuration pertaining to that network SSID.
A minimal example file to connect to a WPA2/PSK secured network with SSID "spaceship" and passphrase "test1234":
/var/lib/iwd/spaceship.psk
[Security] PreSharedKey=aafb192ce2da24d8c7805c956136f45dd612103f086034c402ed266355297295
The PreSharedKey can be calculated with wpa_passphrase (from wpa_supplicant) from the SSID and the WIFI passphrase:
$ wpa_passphrase "spaceship" "test1234"
network={ ssid="spaceship" #psk="test1234" psk=aafb192ce2da24d8c7805c956136f45dd612103f086034c402ed266355297295 }
- _
. If it contains any other characters, the name will instead be an =
-character followed by the hex-encoded version of the SSID.Disable auto-connect for a particular network
Create / edit file /var/lib/iwd/network.type
. Add the following section to it:
/var/lib/iwd/spaceship.psk (for example)
[Settings] Autoconnect=false
Disable periodic scan for available networks
By default when iwd
is in disconnected state, it periodically scans for available networks. To disable periodic scan (so as to always scan manually), create / edit file /etc/iwd/main.conf
and add the following section to it:
/etc/iwd/main.conf
[Scan] disable_periodic_scan=true
Enable built-in network configuration
Since version 0.19, iwd can assign IP address(es) and set up routes using a built-in DHCP client or with static configuration.
To activate iwd's network configuration feature, create/edit /etc/iwd/main.conf
and add the following section to it:
/etc/iwd/main.conf
[General] enable_network_config=true
There is also ability to set route metric with route_priority_offset
:
/etc/iwd/main.conf
[General] route_priority_offset=300
Setting static IP address in network configuration
Add the following section to /var/lib/iwd/network.type
file. For example:
/var/lib/iwd/spaceship.psk
[IPv4] ip=192.168.1.10 netmask=255.255.255.0 gateway=192.168.1.1 broadcast=192.168.1.255 dns=192.168.1.1
Select DNS manager
At the moment, iwd supports two DNS managers—systemd-resolved and resolvconf.
Add the following section to /etc/iwd/main.conf
for systemd-resolved
:
/etc/iwd/main.conf
[General] dns_resolve_method=systemd
For resolvconf
:
/etc/iwd/main.conf
[General] dns_resolve_method=resolvconf
Deny console (local) user from modifying the settings
By default iwd
D-Bus interface allows any console user to connect to iwd
daemon and modify the settings, even if that user is not a root user.
If you do not want to allow console user to modify the settings but allow reading the status information, then create a D-Bus configuration file as follows.
/etc/dbus-1/system.d/iwd-strict.conf
<!-- prevent local users from changing iwd settings, but allow reading status information. overrides some part of /usr/share/dbus-1/system.d/iwd-dbus.conf. --> <!-- This configuration file specifies the required security policies for iNet Wireless Daemon to work. --> <!DOCTYPE busconfig PUBLIC "-//freedesktop//DTD D-BUS Bus Configuration 1.0//EN" "http://www.freedesktop.org/standards/dbus/1.0/busconfig.dtd"> <busconfig> <policy at_console="true"> <deny send_destination="net.connman.iwd"/> <allow send_destination="net.connman.iwd" send_interface="org.freedesktop.DBus.Properties" send_member="GetAll" /> <allow send_destination="net.connman.iwd" send_interface="org.freedesktop.DBus.Properties" send_member="Get" /> <allow send_destination="net.connman.iwd" send_interface="org.freedesktop.DBus.ObjectManager" send_member="GetManagedObjects" /> <allow send_destination="net.connman.iwd" send_interface="net.connman.iwd.Device" send_member="RegisterSignalLevelAgent" /> <allow send_destination="net.connman.iwd" send_interface="net.connman.iwd.Device" send_member="UnregisterSignalLevelAgent" /> </policy> </busconfig>
Troubleshooting
Connect issues after reboot
A low entropy pool can cause connection problems in particular noticeable after reboot. See Random number generation for suggestions to increase the entropy pool.
Systemd unit fails on startup due to device not being available
Some users have reported that the provided systemd unit does not wait for the wireless device to become available. [2] Unfortunately, if iwd is started before udev renaming is done, the network device will be blocked and renaming will fail. Thus, the unit fails on startup. [3] The issue can be fixed by forcing iwd to fallback to legacy mode by adding an option to /etc/iwd/main.conf
as follows:
/etc/iwd/main.conf
[General] use_default_interface=true
Another fix is to create a systemd unit with the following content:
/etc/systemd/system/iwd@.service
[Unit] Description=Wireless service on %I BindsTo=sys-subsystem-net-devices-%i.device After=sys-subsystem-net-devices-%i.device [Service] Type=dbus BusName=net.connman.iwd ExecStart=/usr/lib/iwd/iwd --interface %i LimitNPROC=1 Restart=on-failure
Then one can enable the iwd@device.service
unit for the specific wireless device.
Alternatively, set a proper dependency for iwd to run after systemd/udevd by creating a drop-in file as follows: [4]
/etc/systemd/system/iwd.service.d/override.conf
[Unit] After=systemd-udevd.service
If systemd-networkd is used, since both systemd-udevd/networkd play relatively well together, and both are involved, it is reasonable to start iwd after both of them:
/etc/systemd/system/iwd.service.d/override.conf
[Unit] After=systemd-udevd.service systemd-networkd.service
See FS#61367.