iwd
iwd (iNet wireless daemon) is a wireless daemon for Linux written by Intel. 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.
iwd can work in standalone mode or in combination with comprehensive network managers like ConnMan, systemd-networkd and NetworkManager.
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
. - To exit the interactive prompt, send EOF by pressing
Ctrl+d
. - You can use all commands as command line arguments without entering an interactive prompt. For example:
iwctl device wlan0 show
.
To list all available commands:
[iwd]# help
Connect to a network
First, if you do not know your wireless device name, list all Wi-Fi 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
station
and Tab
Tab
, the available devices are displayed, type the first letters of the device and Tab
to complete. The same way, type connect
and Tab
Tab
in order to have the list of available networks displayed. Then, type the first letters of the chosen network followed by Tab
in order to complete the command.If a passphrase is required, you will be prompted to enter it. Alternatively, you can supply it as a command line argument:
$ iwctl --passphrase passphrase station device connect SSID
-
iwd
automatically stores network passphrases in the/var/lib/iwd
directory and uses them to auto-connect in the future. See #Network 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
.
Connect to a network using WPS/WSC
If your network is configured such that you can connect to it by pressing a button (Wikipedia:Wi-Fi Protected Setup), check first that your network device is also capable of using this setup procedure.
[iwd]# wsc list
Then, provided that your device appeared in the above list,
[iwd]# wsc device push-button
and push the button on your router. The procedure works also if the button was pushed beforehand, less than 2 minutes earlier.
If your network requires to validate a PIN number to connect that way, check the help
command output to see how to provide the right options to the wsc
command.
Disconnect from a network
To disconnect from a network:
[iwd]# station device disconnect
Show device and connection information
To display the details of a WiFi device, like MAC address:
[iwd]# device device show
To display the connection state, including the connected network of a Wi-Fi device:
[iwd]# station 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
Network configuration
By default, iwd stores the network configuration in the directory /var/lib/iwd
. The configuration file is named as network.type
, where network is the network SSID and .type is the network type, either .open, .wep, .psk or .8021x. The file is used to store the encrypted PreSharedKey
and optionally the cleartext Passphrase
and can also be created by the user without invoking iwctl
. The file can be used for other configuration pertaining to that network SSID as well. For more settings, see iwd.network(5).
WPA-PSK
A minimal example file to connect to a WPA-PSK or WPA2-PSK secured network with SSID "spaceship" and passphrase "test1234":
/var/lib/iwd/spaceship.psk
[Security] PreSharedKey=aafb192ce2da24d8c7805c956136f45dd612103f086034c402ed266355297295
- _
. If it contains any other characters, the name will instead be an =
-character followed by the hex-encoded version of the SSID.
To calculate the pre-shared key from the passphrase, one of these two methods can be used:
- Enter the passphrase in cleartext in the configuration file:
/var/lib/iwd/spaceship.psk
[Security] Passphrase=test1234
The pre-shared key will be appended to the file at the first connect:
/var/lib/iwd/spaceship.psk
[Security] Passphrase=test1234 PreSharedKey=aafb192ce2da24d8c7805c956136f45dd612103f086034c402ed266355297295
- Or the pre-shared key can be calculated from the SSID and the passphrase using wpa_passphrase (from wpa_supplicant) or wpa-pskAUR. See wpa_supplicant#Connecting with wpa_passphrase for more details.
WPA Enterprise
EAP-PWD
For connecting to a EAP-PWD protected enterprise access point you need to create a file called: essid.8021x
in the /var/lib/iwd
directory 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
file in the directory. 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-ServerDomainMask=radius.realm.edu EAP-PEAP-Phase2-Method=MSCHAPV2 EAP-PEAP-Phase2-Identity=johndoe@realm.edu EAP-PEAP-Phase2-Password=hunter2 [Settings] AutoConnect=true
MsCHAPv2 passwords can also be stored as a encrypted hash. The correct md4 hash can be calculated with: (insert an EOF after your password, do not hit enter)
$ iconv -t utf16le | openssl md4
The resulting hash needs to be stored inside the EAP-PEAP-Phase2-Password-Hash
key.
TTLS-PAP
Like EAP-PWD, you also need to create a essid.8021x
file in the directory. 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 PAP password authentication:
/var/lib/iwd/essid.8021x
[Security] EAP-Method=TTLS EAP-Identity=anonymous@uni-test.de EAP-TTLS-CACert=cert.pem EAP-TTLS-ServerDomainMask=*.uni-test.de EAP-TTLS-Phase2-Method=Tunneled-PAP EAP-TTLS-Phase2-Identity=user EAP-TTLS-Phase2-Password=password [Settings] AutoConnect=true
eduroam
eduroam offers a configuration assistant tool (CAT), which unfortunately does not support iwd. However, the installer, which you can download by clicking on the download button then selecting your university, is just a Python script. It is easy to extract the necessary configuration options, including the certificate and server domain mask.
The following table contains a mapping of iwd configuration options to eduroam CAT install script variables.
Iwd Configuration Option | CAT Script Variable |
---|---|
file name | one of Config.ssids
|
EAP-Method |
Config.eap_outer
|
EAP-Identity |
Config.anonymous_identity
|
EAP-PEAP-CACert |
Config.CA
|
EAP-PEAP-ServerDomainMask |
one of Config.servers
|
EAP-PEAP-Phase2-Method |
Config.eap_inner
|
EAP-PEAP-Phase2-Identity |
username@Config.user_realm
|
-
EAP-Identity
may not be required by your eduroam provider, in which case you might have to useanonymous@Config.user_realm
in this field. - If your
EAP-PEAP-ServerDomainMask
starts withDNS:
, use only the part afterDNS:
.
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. See iwd.config(5).
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] DisablePeriodicScan=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. It is a good alternative to standalone DHCP clients.
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] EnableNetworkConfiguration=true
There is also ability to set route metric with RoutePriorityOffset
:
/etc/iwd/main.conf
[Network] RoutePriorityOffset=300
IPv6 support
Since version 1.10, iwd supports IPv6, but it is disabled by default. To enable it, add the following to the configuration file:
/etc/iwd/main.conf
[Network] EnableIPv6=true
This setting is required whether you want to use DHCPv6 or static IPv6 configuration. It can also be set on a per-network basis.
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] Address=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
[Network] NameResolvingService=systemd
For resolvconf
:
/etc/iwd/main.conf
[Network] NameResolvingService=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
Verbose TLS debugging
This can be useful, if you have trouble setting up MSCHAPv2 or TTLS. You can set the following environment variable via a drop-in snippet:
/etc/systemd/system/iwd.service.d/tls-debug.conf
[Service] Environment=IWD_TLS_DEBUG=TRUE
Check the iwd logs afterwards by running journalctl -u iwd.service
as root.
Restarting iwd.service after boot
On some machines, it is reported that iwd.service
has to be restarted to work after boot. See FS#63912 and thread 251432. This probably occurs because the Linux kernel and services start too early and iwd starts before wireless network card powers on. As a workaround, extend the unit to add a delay:
[Service] ExecStartPre=/usr/bin/sleep 2
Then reload the systemd manager configuration.
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.
Wireless device is not renamed by udev
Since version 1.0, iwd disables predictable renaming of wireless device. It installs the following systemd network link configuration file which prevents udev from renaming the interface to wlp#s#
:
/usr/lib/systemd/network/80-iwd.link
[Match] Type=wlan [Link] NamePolicy=keep kernel
As a result the wireless link name wlan#
is kept after boot. This resolved a race condition between iwd and udev on interface renaming as explained in iwd udev interface renaming.
If this results in issues try masking it with:
# ln -s /dev/null /etc/systemd/network/80-iwd.link
No DHCP in AP mode
Clients may not receive an IP address via DHCP when connecting to iwd in AP mode. It is therefore necessary to enable network configuration by iwd on managed interfaces:
/etc/iwd/main.conf
[General] EnableNetworkConfiguration=True
The mentioned file has to be created if it does not already exist.
See also
- Getting Started with iwd
- Network Configuration Settings
- More Examples for WPA Enterprise
- The IWD thread on the Arch Linux Forums
- 2017 Update on new WiFi daemon for Linux by Marcel Holtmann - YouTube
- The New Wi-Fi Experience for Linux - Marcel Holtmann, Intel - YouTube
- How to set up a simple access point with iwd