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Edited (4f18dd0) at 2023-07-07 by Dylan Araps
WPA_SUPPLICANT [0]
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wpa_supplicant is a cross-platform supplicant with support for WEP, WPA and WPA2
(IEEE 802.11i). It is suitable for desktops, laptops and embedded systems. It is
the IEEE 802.1X/WPA component that is used in the client stations. It implements
key negotiation with a WPA authenticator and it controls the roaming and IEEE
802.11 authentication/association of the wireless driver.
Configuration
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Begin by first verifying that you have wpa_supplicant installed:
+------------------------------------------------------------------------------+
| |
| $ kiss b wpa_supplicant |
| |
+------------------------------------------------------------------------------+
At this point, you will want to create a wpa_supplicant file to store your
wireless network information and credentials:
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| $ mkdir -p /etc/wpa_supplicant |
| $ touch /etc/wpa_supplicant/wpa_supplicant.conf |
| |
+------------------------------------------------------------------------------+
The following wpa_supplicant.conf can be used as a *starter* configuration
file. Remember to replace the BSSID and PASSWORD with your actual wireless
network credentials.
+------------------------------------------------------------------------------+
| |
| # Allow users in the 'wheel' group to control wpa_supplicant |
| ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=wheel |
| |
| # Make this file writable for wpa_gui / wpa_cli |
| update_config=1 |
| |
| network={ |
| ssid="BSSID" |
| psk="PASSWORD" |
| } |
| |
+------------------------------------------------------------------------------+
For additional network requirements, refer to the "wpa_supplicant" Arch Linux
Wiki page [0].
Generating a Passphrase
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NOTE: This section is not required but HIGHLY recommended since storing your
password in clear text is not good practice.
To allow for quicker connections to a network whose BSSID is already known, we
can make use of wpa_passphrase, a command line tool which generates the minimal
configuration needed by wpa_supplicant:
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| $ wpa_passphrase BSSID PASSWORD |
| |
+------------------------------------------------------------------------------+
Replace BSSID and PASSWORD with your actual wireless network credentials. The
output of this command can then be used to replace the network section of the
wpa_supplicant.conf file created in the previous section (just remember to
delete the line containing your password in clear text).
Manual Wireless Connection
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A new wireless connection can be manually started with the following command:
+------------------------------------------------------------------------------+
| |
| $ wpa_supplicant -B -i INTERFACE \ |
| -c /etc/wpa_supplicant/wpa_supplicant.conf |
| |
+------------------------------------------------------------------------------+
Replace INTERFACE with your appropriate wireless LAN interface name. After,
use your preferred method to manually obtain an IP address. For example, when
using dhcpcd, run the following:
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| $ dhcpcd INTERFACE |
| |
+------------------------------------------------------------------------------+
The wireless status connection can be verified by reviewing the output of the
following command:
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| $ ifconfig |
| |
+------------------------------------------------------------------------------+
Managed Wireless Connection via dhcpcd
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Assuming that dhcpcd is already installed, busybox's runsv can be used to create
new managed services for wpa_supplicant and dhcpcd:
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| |
| $ ln -s /usr/share/dhcpcd/hooks/10-wpa_supplicant \ |
| /usr/lib/dhcpcd/dhcpcd-hooks/ |
| $ ln -s /etc/sv/dhcpcd/ /var/service |
| |
+------------------------------------------------------------------------------+
Tips and Tricks
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* A list of possible INTERFACE names can be obtained by running the following:
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| $ ls /sys/class/net |
| |
+----------------------------------------------------------------------------+
* While testing arguments/configuration it may be helpful to launch
wpa_supplicant in the foreground (i.e. without the -B option) for better
debugging messages.
References
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[0] https://wiki.archlinux.org/index.php/wpa_supplicant
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Dylan Araps (C) 2019-2021
The registered trademark Linux(R) is used pursuant to a sublicense from the
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on a worldwide basis.