X-Git-Url: https://git.rohieb.name/openwrt.git/blobdiff_plain/8fb079219b9d59341d27e18aefcb306693b7b66c..8d00b42964662d768a1d86e100eb473f8de4f768:/docs/wireless.tex

diff --git a/docs/wireless.tex b/docs/wireless.tex
index 6b3ffbac7..7e9623972 100644
--- a/docs/wireless.tex
+++ b/docs/wireless.tex
@@ -1,8 +1,15 @@
 The WiFi settings are configured in the file \texttt{/etc/config/wireless}
 (currently supported on Broadcom and Atheros). When booting the router for the first time
-it should detect your card and create a sample configuration that looks like this:
+it should detect your card and create a sample configuration file. By default '\texttt{option network  lan}' is
+commented. This prevents unsecured sharing of the network over the wireless interface.
 
-\paragraph{Sample Broadcom wireless config:}
+Each wireless driver has its own configuration script in \texttt{/lib/wifi/driver\_name.sh} which handles
+driver specific options and configurations. This script is also calling driver specific binaries like wlc for
+Broadcom, or hostapd and wpa\_supplicant for atheros.
+
+The reason for using such architecture, is that it abstracts the driver configuration. 
+
+\paragraph{Generic Broadcom wireless config:}
 
 \begin{Verbatim}
 config wifi-device      "wl0"
@@ -11,41 +18,97 @@ config wifi-device      "wl0"
 
 config wifi-iface
     option device       "wl0"
+#   option network  lan
     option mode         "ap"
     option ssid         "OpenWrt"
     option hidden       "0"
     option encryption   "none"
 \end{Verbatim}
 
-\paragraph{Sample Atheros wireless config:}
+\paragraph{Generic Atheros wireless config:}
 
 \begin{Verbatim}
 config wifi-device      "wifi0"
     option type         "atheros"
     option channel      "5"
-	option mode  		"11g"
+    option agmode  	"11g"
 
 config wifi-iface
     option device       "wifi0"
+#   option network  lan
     option mode         "ap"
     option ssid         "OpenWrt"
     option hidden       "0"
     option encryption   "none"
 \end{Verbatim}
 
+\paragraph{Generic multi-radio Atheros wireless config:}
+
+\begin{Verbatim}
+config wifi-device  wifi0
+    option type     atheros
+    option channel  1
+
+config wifi-iface
+    option device   wifi0
+#   option network  lan
+    option mode     ap
+    option ssid     OpenWrt_private
+    option hidden   0
+    option encryption none
+
+config wifi-device  wifi1
+    option type     atheros
+    option channel  11
+
+config wifi-iface
+    option device   wifi1
+#   option network  lan
+    option mode     ap
+    option ssid     OpenWrt_public
+    option hidden   1
+    option encryption none
+\end{Verbatim}
+
 There are two types of config sections in this file. The '\texttt{wifi-device}' refers to
 the physical wifi interface and '\texttt{wifi-iface}' configures a virtual interface on top
 of that (if supported by the driver).
 
+A full outline of the wireless configuration file with description of each field:
+
+\begin{Verbatim}
+config wifi-device     wifi device name
+    option type     broadcom, atheros
+    option country  us, uk, fr, de, etc.
+    option channel  1-14
+    option maxassoc 1-128 (broadcom only)
+    option distance 1-n
+    option agmode     11b, 11g, 11a, 11bg (atheros only)
+
+config wifi-iface
+    option network  the interface you want wifi to bridge with 
+    option device   wifi0, wifi1, wifi2, wifiN
+    option mode     ap, sta, adhoc, or wds
+    option ssid     ssid name
+    option bssid    bssid address
+    option encryption none, wep, psk, psk2, wpa, wpa2 
+    option key      encryption key
+    option key1     key 1
+    option key2     key 2
+    option key3     key 3
+    option key4     key 4
+    option server   ip address
+    option port     port
+    option hidden   0,1
+    option isolate  0,1
+\end{Verbatim}
+
 \paragraph{Options for the \texttt{wifi-device}:}
 
 \begin{itemize}
     \item \texttt{type} \\
         The driver to use for this interface.
 	
-	\item \texttt{mode} \\
-		The frequency band (\texttt{b}, \texttt{g}, \texttt{bg}, \texttt{a})
-
     \item \texttt{country} \\
         The country code used to determine the regulatory settings.
 
@@ -53,13 +116,27 @@ of that (if supported by the driver).
         The wifi channel (e.g. 1-14, depending on your country setting).
 
     \item \texttt{maxassoc} \\
-        Maximum number of associated clients
+        Optional: Maximum number of associated clients. This feature is supported only on the broadcom chipset.
+
+    \item \texttt{distance} \\
+	Optional: Distance between the ap and the furthest client in meters. This feature is supported only on the atheros chipset.
+
+	\item \texttt{mode} \\
+		The frequency band (\texttt{b}, \texttt{g}, \texttt{bg}, \texttt{a}). This feature is only supported on the atheros chipset.
+
 
 \end{itemize}
 
 \paragraph{Options for the \texttt{wifi-iface}:}
 
 \begin{itemize}
+    \item \texttt{network} \\
+        Selects the interface section from \texttt{/etc/config/network} to be
+        used with this interface
+
+    \item \texttt{device} \\
+	Set the wifi device name.
+
     \item \texttt{mode} \\
         Operating mode:
 
@@ -78,35 +155,47 @@ of that (if supported by the driver).
 
         \end{itemize}
 
-    \item \texttt{network} \\
-        Selects the interface section from \texttt{/etc/config/network} to be
-        used with this interface
+    \item \texttt{ssid}
+	Set the SSID to be used on the wifi device.
+
+    \item \texttt{bssid}
+	Set the BSSID address to be used for wds to set the mac address of the other wds unit.
 
     \item \texttt{encryption} \\
         Encryption setting. Accepts the following values:
 
         \begin{itemize}
+	    \item \texttt{none}
+	    \item \texttt{wep}
             \item \texttt{psk}, \texttt{psk2} \\
                 WPA(2) Pre-shared Key
 
             \item \texttt{wpa}, \texttt{wpa2} \\
                 WPA(2) RADIUS
-
         \end{itemize}
 
-    \item \texttt{key} (wpa and psk) \\
-        Either the WPA key (PSK mode) or the RADIUS shared secret (WPA RADIUS mode)
+    \item \texttt{key, key1, key2, key3, key4} (wep, wpa and psk) \\
+        WEP key, WPA key (PSK mode) or the RADIUS shared secret (WPA RADIUS mode)
 
     \item \texttt{server} (wpa) \\
-        The RADIUS server address
+        The RADIUS server ip address
 
     \item \texttt{port} (wpa) \\
         The RADIUS server port
 
+    \item \texttt{hidden} \\
+        0 broadcasts the ssid; 1 disables broadcasting of the ssid
+
+    \item \texttt{isolate} \\
+        Optional: Isolation is a mode usually set on hotspots that limits the clients to communicate only with the AP and not with other wireless clients.
+        0 disables ap isolation (default); 1 enables ap isolation.
+
 \end{itemize}
 
+
 \paragraph{Limitations:}
 
+There are certain limitations when combining modes.
 Only the following mode combinations are supported:
 
 \begin{itemize}
@@ -117,7 +206,7 @@ Only the following mode combinations are supported:
             \item 1x \texttt{adhoc}
         \end{itemize}
 
-        WDS links can only be used in pure AP mode and can't use WEP (except when sharing the
+        WDS links can only be used in pure AP mode and cannot use WEP (except when sharing the
         settings with the master interface, which is done automatically).
 
     \item \textbf{Atheros}: \\
@@ -126,7 +215,104 @@ Only the following mode combinations are supported:
             \item 1-4x \texttt{ap}
             \item 1x \texttt{adhoc}
         \end{itemize}
+\end{itemize}
 
+\paragraph{Adding a new driver configuration}
+
+Since we currently only support two different wireless drivers : Broadcom and Atheros,
+you might be interested in adding support for another driver like Ralink RT2x00, 
+Texas Instruments ACX100/111.
+
+The driver specific script should be placed in \texttt{/lib/wifi/<driver>.sh} and has to
+include several functions providing :
+
+\begin{itemize}
+	\item detection of the driver presence
+	\item enabling/disabling the wifi interface(s)
+	\item configuration reading and setting
+	\item third-party programs calling (nas, supplicant)
 \end{itemize}
 
+Each driver script should append the driver to a global DRIVERS variable :
+
+\begin{Verbatim}
+append DRIVERS "driver name"
+\end{Verbatim}
+
+\subparagraph{\texttt{scan\_<driver>}}
+
+This function will parse the \texttt{/etc/config/wireless} and make sure there
+are no configuration incompatibilities, like enabling hidden SSIDS with ad-hoc mode
+for instance. This can be more complex if your driver supports a lof of configuration
+options. It does not change the state of the interface.
+
+Example:
+\begin{Verbatim}
+scan_dummy() {
+	local device="$1"
+
+	config_get vifs "$device" vifs
+	for vif in $vifs; do
+		# check config consistency for wifi-iface sections
+	done
+	# check mode combination
+}
+\end{Verbatim}
+
+\subparagraph{\texttt{enable\_<driver>}}
+
+This function will bring up the wifi device and optionally create application specific
+configuration files, e.g. for the WPA authenticator or supplicant.
+
+Example:
+\begin{Verbatim}
+enable_dummy() {
+	local device="$1"
+
+	config_get vifs "$device" vifs
+	for vif in $vifs; do
+		# bring up virtual interface belonging to
+		# the wifi-device "$device"
+	done
+}
+\end{Verbatim}
+
+\subparagraph{\texttt{disable\_<driver>}}
+
+This function will bring down the wifi device and all its virtual interfaces (if supported).
+
+Example:
+\begin{Verbatim}
+disable_dummy() {
+	local device="$1"
+
+	# bring down virtual interfaces belonging to
+	# "$device" regardless of whether they are
+	# configured or not. Don't rely on the vifs
+	# variable at this point
+}
+\end{Verbatim}
+
+\subparagraph{\texttt{detect\_<driver>}}
+
+This function looks for interfaces that are usable with the driver. Template config sections
+for new devices should be written to stdout. Must check for already existing config sections
+belonging to the interfaces before creating new templates.
 
+Example:
+\begin{Verbatim}
+detect_dummy() {
+	[ wifi-device = "$(config_get dummydev type)" ] && return 0
+	cat <<EOF
+config wifi-device dummydev
+	option type dummy
+	# REMOVE THIS LINE TO ENABLE WIFI:
+	option disabled 1
+
+config wifi-iface
+	option device dummydev
+	option mode ap
+	option ssid OpenWrt
+EOF
+}
+\end{Verbatim}
