libbsd.txt: Describe current state of WLAN.

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Christian Mauderer 2017-11-08 12:43:39 +01:00 committed by Sebastian Huber
parent bed8742caa
commit e5abb31577

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@ -1154,6 +1154,58 @@ The following is necessary to use PF on RTEMS:
systems (on FreeBSD that means systems with less than 100 MB RAM). This is
fixed in +pfctl_init_options()+.
== Wireless Network (WLAN) ==
The libbsd provides a basic support for WLAN. Note that currently this support
is still in an early state. The following gives a rough overview over the
necessary steps to connect to an encrypted network with an RTL8188EU based WiFi
dongle:
- Reference all necessary module for your BSP. For some BSPs this is already
done in the nexus-devices.h:
----
SYSINIT_MODULE_REFERENCE(wlan_ratectl_none);
SYSINIT_MODULE_REFERENCE(wlan_sta);
SYSINIT_MODULE_REFERENCE(wlan_amrr);
SYSINIT_MODULE_REFERENCE(wlan_wep);
SYSINIT_MODULE_REFERENCE(wlan_tkip);
SYSINIT_MODULE_REFERENCE(wlan_ccmp);
SYSINIT_DRIVER_REFERENCE(rtwn_usb, uhub);
SYSINIT_REFERENCE(rtwn_rtl8188eufw);
----
- Create your wlan device using ifconfig:
+ifconfig wlan0 create wlandev rtwn0 up+
- Start a wpa_supplicant instance for that device:
+ wpa_supplicant_fork -Dbsd -iwlan0 -c/media/mmcsd-0-0/wpa_supplicant.conf+
Note that the wpa_supplicant will only be active till the device goes down. A
workaround is to just restart it every time it exits.
=== Known restrictions ===
- The network interface (e.g. wlan0) is currently not automatically created. It
would be nice, if some service would create it as soon as for example a USB
device is connected. In FreeBSD the names are assigned via rc.conf with lines
like +wlans_rtwn0="wlan0"+.
- wpa_supplicant hast to be started after the device is created. It has to be
restarted every time the connection goes down. Instead of this behaviour,
there should be some service that starts and restarts wpa_supplicant
automatically if a interface is ready. Probably the dhcpcd hooks could be used
for that.
- The current wpa_supplicant implementation is protected with a lock so it can't
be started more than one time. If multiple interface should be used, all have
to be handled by that single instance. That makes it hard to add interfaces
dynamically. wpa_supplicant should be reviewed thoroughly whether multiple
instances could be started in parallel.
- The control interface of wpa_supplicant most likely doesn't work. The wpa_cli
application is not ported.
== Problems to report to FreeBSD ==
The MMAP_NOT_AVAILABLE define is inverted on its usage. When it is