Atheros AP222A, Руководство пользователя

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COMPANY CONFIDENTIAL 8
2 User Interface
The user interface on the Linux AP baseline provides a rich set of capabilities via command line tools, and also provides a
simplified web interface that can be used for quick AP configuration. The user interface is based on shell scripts and a
configuration utility that will store configuration information in flash. The web interface also uses this utility to store
information through boot cycles.
2.1 Factory Default File
The file
/etc/ath/apcfg
contains the “factory default” information for the AP. This is the data that is used to configure
the device in the absence of other configuration information. If the configuration information is erased, this data will
repopulate the configuration information files. The default values included in this file can be changed if the user so
desires.
2.2 Configuration Tool
The purpose of the cgiMain utility is to provide a small program size mechanism for managing environmental
configuration information in as efficient manner as possible. Major consideration has been applied to small footprint
environments, where JFFS2 filesystem space is at a premium. Further, if no configuration information needs to be
changed in the JFFS2 filesystem, the cramfs can be used to further reduce the flash footprint of the overall system.
2.2.1 Design
The main design intent was to provide a busybox like environment that can be used as a CGI program for getting
environmental information, and further providing output formatting that will make the web pages easily configurable,
but dynamic. This was done in lieu of other larger implementations, such as PHP or Python, simply for the smaller size
requirement, and the customization required to use flash resources effectively.
The main engine will receive an input file and “translate” it, changing specially tagged parameters into their equivalent
values. For example, let’s say that we have an environmental variable called AP_SSID, whose value is AP24. Further,
let’s say we have a configuration file that has a line in the file of the form
ssid=<ssid value>.
We can put a tagged reference to the environmental variable in the configuration file, and then “translate” it to a scratch
file:
Original file: ssid=~~AP_SSID~
Translated file: ssid=AP24
The translated file can be written to /tmp (ram disk), thus not requiring any more flash space to support the translation.
A typical command line to implement this would be
# cgiMain –t2 /etc/ath/PSK.ap_bss > /tmp/vap2sec.bss
Where /etc/ath/PSK.ap_bss is the file containing the tags, and /tmp/vap0sec.bss is the file containing the translated
version with tags replaced with values.