users-guide.tex

Linux下wifi实现

\end{example}
\begin{example}
  Now, we wish to destroy a VAP (regardless of its operating mode).
  We assume that there is a VAP named \mytt{ath0}, and it's the one
  we wish to destroy.
  \bv
  \cmd{wlanconfig ath0 destroy}
  \ev
\end{example}

\subsection{Private (Driver Specific) Driver Commands}
\label{sec:iwprivs}
The following is a list of the private commands which are accessible
using \mytt{iwpriv}.  The general syntax of \mytt{iwpriv} is
\bv
\mytt{iwpriv} \textit{device} [\textit{command}]
[\textit{parameters}].
\ev
The entire list of \mytt{iwpriv} commands can be found by running
\mytt{iwpriv} to a device without any command.  The resulting list of
commands has several columns.  The number of parameters allowed for
each command is listed.  Parameters are classified as either ``set''
or ``get'' parameters.  ``Set'' parameters are parameters which the
user supplies to the driver.  ``Get'' parameters are parameters which
the driver returns to the user.

\subsubsection{\mytt{setoptie} - Set Optional Information Element}
\argdesc{1}{0}{??}{??}
This command takes a 256 byte input parameter which specifies?

\subsubsection{\mytt{getoptie} - Get Optional Information Element}
\argdesc{0}{1}{N/A}{??}
This command gets the optional information element.  The information
element is returned as 256 bytes.

\subsubsection{\mytt{mode} - Set Wireless Mode}
\argdesc{1}{0}{auto}{Yes}
This command sets the wireless mode, i.e. the frequency band and the
protocol used.  The mode can be specified either by name or by number. 
The allowed mode names and corresponding numbers are given in
Table~\ref{tab:mode}.
\begin{table}[h*]
  \centering
  \begin{tabular}{|l|l|l|} \hline
    Mode & Number & Description \\ \hline
    auto & 0 & Auto select operating mode \\
    11a & 1 & 802.11a (5GHz) mode (54Mbps) \\
    11b & 2 & 802.11b (2.4GHz) mode (11Mbps) \\
    11g & 3 & 802.11g (2.4GHz) mode with 802.11b compatibility (54Mbps) \\
    fh & 4 & 802.11 frequency hopping mode \\
    11adt/111at & 5 & 802.11a (5GHz) dynamic turbo mode \\
    11gdt/11gt & 6 & 802.11g (2GHz) dynamic turbo mode (108Mbps) \\
    11ast & 7 & 802.11a (5GHz) static turbo mode \\ \hline
  \end{tabular}
  \caption{802.11 Operating Modes}
  \label{tab:mode}
\end{table}
\begin{example}
  Either of the following two commands will set the wireless operating
  mode on a device named \mytt{ath0} to use 802.11a dynamic turbo:
  \bv
  \cmd{iwpriv ath0 mode 11a}
  \ev
  or
  \bv
  \cmd{iwpriv ath0 mode 1}
  \ev
\end{example}

\subsubsection{\mytt{get\_mode} - Get Wireless Mode}
\argdesc{0}{1}{N/A}{No}
This command returns the wireless mode of VAP.  The returned values
correspond to the modes given in Table~\ref{tab:mode}.
\begin{example}
  The following command retrieves the wireless mode of a device named
  \mytt{ath0} which we will assume is operating in the 802.11g mode:
  \bv
  \cmd{iwpriv ath0 get\_mode}\\
  \mytt{ath0\hspace{32pt}get\_mode:11g}
  \ev
\end{example}

\subsubsection{\mytt{hide\_ssid} - Enable/Disable Hiding of the 802.11 SSID}
\argdesc{1}{0}{Disabled}{Yes}
This command enables and disables the ability to hide the 802.11 SSID
in the beacon if the VAP is in AP mode.  To enable hiding of the SSID,
a value of 1 is passed into the driver. To disable hiding of the SSID,
a value of 0 is passed into the driver.
\begin{example}
  The following command enables hiding the 802.11 SSID on \mytt{ath0}:
  \bv
  \cmd{iwpriv ath0 hide\_ssid 1}
  \ev
\end{example}

\subsubsection{\mytt{get\_hide\_ssid} - Get Status of 802.11 SSID
  Hiding Support}
\argdesc{0}{1}{N/A}{No}
This command returns whether the driver is currently hiding the 802.11
SSID in beacons.  A value of 1 indicates that the VAP is hiding the
802.11 SSID.  A value of 0 indicates the VAP is not hiding the 802.11
SSID.
\begin{example}
  The following command retrieves whether \mytt{ath0} is hiding the
  802.11 SSID in its beacon:
  \bv
  \cmd{iwpriv ath0 get\_hide\_ssid}\\
  \mytt{ath0\hspace{32pt}get\_hide\_ssid:0}
  \ev
\end{example}

\subsubsection{\mytt{protmode} - Enable/Disable 802.11g Protection Mode}
\argdesc{1}{0}{Enabled}{Yes}
This command enables and disables the 802.11g protection mode.  To
enable 802.11g protection, a value of 1 is passed into the driver. To
disable 802.11g protection, a value of 0 is passed into the driver.
\begin{example}
  The following command disables 802.11g protection on \mytt{ath0}:
  \bv
  \cmd{iwpriv ath0 protmode 0}
  \ev
\end{example}

\subsubsection{\mytt{get\_protmode} - Get Status of 802.11g Protection
  Mode}
\argdesc{0}{1}{N/A}{No}
This command returns whether the driver is currently using 802.11g
protection mode. A value of 1 indicates that the VAP is using 802.11g
protection.  A value of 0 indicates the VAP is not using 802.11g
protection.
\begin{example}
  The following command retrieves whether \mytt{ath0} is using 802.11g
  protection mode:
  \bv
  \cmd{iwpriv ath0 get\_protmode}\\
  \mytt{ath0\hspace{32pt}get\_protmode:1}
  \ev
\end{example}

\subsubsection{\mytt{inact\_init} - Set Inactivity Period for INIT
  State}
\argdesc{1}{0}{30 secs}{No}
This commands sets the inactivity period for when the net80211 state
machine is in the INIT (initialization) state.  The argument passed
into the driver is the desired inactivity period in seconds.
\begin{example}
  The following command sets the inactivity period for the INIT state
  on \mytt{ath0} to 90 seconds:
  \bv
  \cmd{iwpriv ath0 inact\_init 90}\\
  \ev
\end{example}

\subsubsection{\mytt{get\_inact\_init} - Get Inactivity Period for INIT
  State}
\argdesc{0}{1}{N/A}{No}
This commands gets the inactivity period for when the net80211 state
machine is in the INIT (initialization) state.
\begin{example}
  The following command gets the inactivity period for the INIT state
  on \mytt{ath0}:
  \bv
  \cmd{iwpriv ath0 get\_inact\_init}\\
  \mytt{ath0\hspace{32pt}get\_inact\_init:30}
  \ev
\end{example}

\subsubsection{\mytt{inact\_auth} - Set Inactivity Period for AUTH
  State}
\argdesc{1}{0}{180 secs}{No}
This commands sets the inactivity period for when the net80211 state
machine is in the AUTH (authorization) state.  The argument passed
into the driver is the desired inactivity period in seconds.
\begin{example}
  The following command sets the inactivity period for the AUTH state
  on \mytt{ath0} to 90 seconds:
  \bv
  \cmd{iwpriv ath0 inact\_auth 90}\\
  \ev
\end{example}

\subsubsection{\mytt{get\_inact\_auth} - Get Inactivity Period for AUTH
  State}
\argdesc{0}{1}{N/A}{No}
This commands gets the inactivity period for when the net80211 state
machine is in the AUTH (authorization) state.
\begin{example}
  The following command gets the inactivity period for the AUTH state
  on \mytt{ath0}:
  \bv
  \cmd{iwpriv ath0 get\_inact\_auth}\\
  \mytt{ath0\hspace{32pt}get\_inact\_auth:180}
  \ev
\end{example}

\subsubsection{\mytt{inact} - Set Inactivity Period for RUN
  State}
\argdesc{1}{0}{300 secs}{No}
This commands sets the inactivity period for when the net80211 state
machine is in the RUN (running) state.  The argument passed into the
driver is the desired inactivity period in seconds.
\begin{example}
  The following command sets the inactivity period for the RUN state
  on \mytt{ath0} to 90 seconds:
  \bv
  \cmd{iwpriv ath0 inact 90}
  \ev
\end{example}

\subsubsection{\mytt{get\_inact} - Get Inactivity Period for RUN
  State}
\argdesc{0}{1}{N/A}{No}
This commands gets the inactivity period for when the net80211 state
machine is in the RUN (running) state.
\begin{example}
  The following command gets the inactivity period for the RUN state
  on \mytt{ath0}:
  \bv
  \cmd{iwpriv ath0 get\_inact}\\
  \mytt{ath0\hspace{32pt}get\_inact:300}
  \ev
\end{example}

\subsubsection{\mytt{dtim\_period} - Set DTIM Period}
\argdesc{1}{0}{N/A}{Yes}
This command sets the beacon DTIM period.  The argument passed to the
driver is the desired DTIM period in ms.
\begin{example}
  The following command sets the DTIM period to 2 ms on \mytt{ath0}:
  \bv
  \cmd{iwpriv ath0 dtim\_period 2}
  \ev
\end{example}

\subsubsection{\mytt{get\_dtim\_period} - Get Beacon DTIM Period}
\argdesc{0}{1}{N/A}{No}
This command gets the current beacon DTIM in ms.
\begin{example}
  The following command gets the DTIM period on \mytt{ath0}:
  \bv
  \cmd{iwpriv ath0 get\_dtim\_period}\\
  \mytt{ath0\hspace{32pt}get\_dtim\_period:1}
  \ev
\end{example}

\subsubsection{\mytt{bintval} - Set Beacon Interval Value}
\argdesc{1}{0}{N/A}{Yes}
This command sets the beacon interval.  The argument passed to the
driver is the desired beacon interval in ms.
\begin{example}
  The following command sets the beacon interval to 25 ms on
  \mytt{ath0}:
  \bv
  \cmd{iwpriv ath0 bintval 25}
  \ev
\end{example}

\subsubsection{\mytt{get\_bintval} - Get Beacon Interval Value}
\argdesc{0}{1}{N/A}{No}
This command gets the current beacon interval in ms.
\begin{example}
  The following command gets the beacon interval on \mytt{ath0}:
  \bv
  \cmd{iwpriv ath0 get\_bintval}\\
  \mytt{ath0\hspace{32pt}get\_bintval:100}
  \ev
\end{example}

\subsubsection{\mytt{doth} - 802.11h Support Enable/Disable}
\argdesc{1}{0}{Disabled}{Yes}
This command enables and disables the 802.11h support.  To enable the
support, a value of 1 is passed into the driver. To disable 802.11h
support, a value of 0 is passed into the driver.
\begin{example}
  The following command enables 802.11h on \mytt{ath0}:
  \bv
  \cmd{iwpriv ath0 doth 1}
  \ev
\end{example}

\subsubsection{\mytt{get\_doth} - Get 802.11h Support Status}
\argdesc{0}{1}{N/A}{No}
This command returns whether 802.11h support is enabled or disabled in
the driver.
\begin{example}
  The following command retrieves the 802.11h status on \mytt{ath0}:
  \bv
  \cmd{iwpriv ath0 get\_doth}\\
  \mytt{ath0\hspace{32pt}get\_doth:0}
  \ev
\end{example}

\subsubsection{\mytt{doth\_reassoc} - Generate a Reassociation Request}
\argdesc{1}{0}{N/A}{No}
This command instructs the driver to generate a Reassociation request.
A single input parameter is needed but ignored.
\begin{example}
  Either of the following commands generates a reassociation request
  on \mytt{ath0}.
  \bv
  \cmd{iwpriv ath0 doth\_reassoc 1}
  \ev
  or
  \bv
  \cmd{iwpriv ath0 doth\_reassoc 0}
  \ev
\end{example}

\subsubsection{\mytt{doth\_pwrtgt} - Set Maximum Desired Power for
  Transmission}
\argdesc{1}{0}{N/A}{No}
This command sets the desired maximum power on the current channel.
The minimum of this desired value and the regulatory maximum is used
as the true transmission power.  The single argument passed into the
driver is the desired power level in 0.5 dBm steps.
\begin{example}
  To set the desired power level on the current channel to be 13 dBm,
  the following command is used:
  \bv
  \cmd{iwpriv ath0 doth\_pwrtgt 26}
  \ev
\end{example}

\subsubsection{\mytt{wpa} - Enable/Disable WPA/WPA2 Support}
\argdesc{1}{0}{Disabled}{Yes}
This command enables or disables WPA or WPA2 support.  A single
argument is passed to the driver indicating which encryption protocols
is to be supported.  Table~\ref{tab:wpa} lists the arguments and the
encryption protocols supported.
\begin{table}
  \centering
  \begin{tabular}{|l|l|} \hline
    Argument & Protocol Supported \\ \hline
    0 & No WPA \\
    1 & WPA Supported \\
    2 & WPA2 Supported \\
    3 & Both WPA and WPA2 supported \\ \hline
  \end{tabular}
  \caption{WPA/WPA2 Support Arguments}
  \label{tab:wpa}
\end{table}
\begin{example}
  To enable both WPA and WPA2, the following command is used:
  \bv
  \cmd{iwpriv ath0 wpa 3}
  \ev
\end{example}

\subsubsection{\mytt{mcastcipher} - Set Group Key Length}
\argdesc{1}{0}{N/A}{No}
This command sets the group key (multicast) key length.  This command is
used mainly by \mytt{hostapd}.  See the \mytt{driver\_madwifi.c} file
in \mytt{hostapd} for details on the use of this command.

\subsubsection{\mytt{get\_mcastcipher} - Get Group Key Length}
\argdesc{0}{1}{N/A}{No}
This command returns the current group key length.  This command is