[generic] revert unrelated change in previous commit

[openwrt.git] / docs / wireless.tex

diff --git a/docs/wireless.tex b/docs/wireless.tex
index 6b3ffba..efb07ea 100644 (file)
--- a/docs/wireless.tex
+++ b/docs/wireless.tex
@@ -1,8 +1,15 @@
 The WiFi settings are configured in the file \texttt{/etc/config/wireless}
 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:
+(currently supported on Broadcom, Atheros and mac80211). When booting the router for the first time
+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 and mac80211.
+
+The reason for using such architecture, is that it abstracts the driver configuration. 
+
+\paragraph{Generic Broadcom wireless config:}

 
 \begin{Verbatim}
 config wifi-device      "wl0"
 
 \begin{Verbatim}
 config wifi-device      "wl0"


@@ -11,41 +18,120 @@ config wifi-device      "wl0"
 
 config wifi-iface
     option 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}
 
     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"
 
 \begin{Verbatim}
 config wifi-device      "wifi0"
     option type         "atheros"
     option channel      "5"

-       option mode             "11g"
+    option hwmode      "11g"

 
 config wifi-iface
     option device       "wifi0"
 
 config wifi-iface
     option device       "wifi0"

+#   option network  lan

     option mode         "ap"
     option ssid         "OpenWrt"
     option hidden       "0"
     option encryption   "none"
 \end{Verbatim}
 
     option mode         "ap"
     option ssid         "OpenWrt"
     option hidden       "0"
     option encryption   "none"
 \end{Verbatim}
 

+\paragraph{Generic mac80211 wireless config:}
+
+\begin{Verbatim}
+config wifi-device      "wifi0"
+    option type         "mac80211"
+    option channel      "5"
+
+config wifi-iface
+    option device       "wlan0"
+#   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).
 
 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, mac80211
+    option country    us, uk, fr, de, etc.
+    option channel    1-14
+    option maxassoc   1-128 (broadcom only)
+    option distance   1-n (meters)
+    option hwmode     11b, 11g, 11a, 11bg (atheros, mac80211)
+    option rxantenna  0,1,2 (atheros, broadcom)
+    option txantenna  0,1,2 (atheros, broadcom)
+    option txpower  transmission power in dBm
+
+config wifi-iface
+    option network  the interface you want wifi to bridge with
+    option device   wifi0, wifi1, wifi2, wifiN
+    option mode     ap, sta, adhoc, monitor, mesh, or wds
+    option txpower  (deprecated) transmission power in dBm
+    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 passphrase 0,1
+    option server   ip address
+    option port     port
+    option hidden   0,1
+    option isolate  0,1        (broadcom)
+    option doth     0,1        (atheros, broadcom)
+    option wmm      0,1        (atheros, broadcom)
+\end{Verbatim}
+

 \paragraph{Options for the \texttt{wifi-device}:}
 
 \begin{itemize}
     \item \texttt{type} \\
         The driver to use for this interface.
        
 \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.
 
     \item \texttt{country} \\
         The country code used to determine the regulatory settings.
 


@@ -53,13 +139,38 @@ of that (if supported by the driver).
         The wifi channel (e.g. 1-14, depending on your country setting).
 
     \item \texttt{maxassoc} \\
         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 chipsets.
+
+    \item \texttt{distance} \\
+       Optional: Distance between the ap and the furthest client in meters. This feature is supported only on the Atheros chipsets.
+
+       \item \texttt{mode} \\
+               The frequency band (\texttt{b}, \texttt{g}, \texttt{bg}, \texttt{a}). This feature is only supported on the Atheros chipsets.
+
+    \item \texttt{diversity} \\
+       Optional: Enable diversity for the Wi-Fi device. This feature is supported only on the Atheros chipsets.
+
+    \item \texttt{rxantenna} \\
+       Optional: Antenna identifier (0, 1 or 2) for reception. This feature is supported by Atheros and some Broadcom chipsets.
+
+    \item \texttt{txantenna} \\
+       Optional: Antenna identifier (0, 1 or 2) for emission. This feature is supported by Atheros and some Broadcom chipsets.
+
+    \item \texttt{txpower}
+       Set the transmission power to be used. The amount is specified in dBm.

 
 \end{itemize}
 
 \paragraph{Options for the \texttt{wifi-iface}:}
 
 \begin{itemize}
 
 \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:
 
     \item \texttt{mode} \\
         Operating mode:
 


@@ -73,40 +184,188 @@ of that (if supported by the driver).
             \item \texttt{adhoc} \\
                 Ad-Hoc mode
 
             \item \texttt{adhoc} \\
                 Ad-Hoc mode
 

+            \item \texttt{monitor} \\
+                Monitor mode
+
+           \item \texttt{mesh} \\
+               Mesh Point mode (802.11s)
+

             \item \texttt{wds} \\
                 WDS point-to-point link
 
         \end{itemize}
 
             \item \texttt{wds} \\
                 WDS point-to-point link
 
         \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{txpower}
+       (Deprecated, set in wifi-device) Set the transmission power to be used. The amount is specified in dBm.

 
     \item \texttt{encryption} \\
         Encryption setting. Accepts the following values:
 
         \begin{itemize}
 
     \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
             \item \texttt{psk}, \texttt{psk2} \\
                 WPA(2) Pre-shared Key
 
             \item \texttt{wpa}, \texttt{wpa2} \\
                 WPA(2) RADIUS

-

         \end{itemize}
 
         \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{passphrase} (wpa) \\
+        0 treats the wpa psk as a text passphrase; 1 treats wpa psk as
+        encoded passphrase. You can generate an encoded passphrase with
+        the wpa\_passphrase utility. This is especially useful if your
+        passphrase contains special characters. This option only works
+        when using mac80211 or atheros type devices.

 
     \item \texttt{server} (wpa) \\
 
     \item \texttt{server} (wpa) \\

-        The RADIUS server address
+        The RADIUS server ip address

 
     \item \texttt{port} (wpa) \\
 
     \item \texttt{port} (wpa) \\

-        The RADIUS server port
+        The RADIUS server port (defaults to 1812)
+
+    \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.
+
+    \item \texttt{doth} \\
+        Optional: Toggle 802.11h mode.
+        0 disables 802.11h (default); 1 enables it.
+
+    \item \texttt{wmm} \\
+        Optional: Toggle 802.11e mode.
+        0 disables 802.11e (default); 1 enables it.

 
 \end{itemize}
 
 
 \end{itemize}
 

+\paragraph{Mesh Point}
+
+Mesh Point (802.11s) is only supported by some mac80211 drivers. It requires the iw package
+to be installed to setup mesh links. OpenWrt creates mshN mesh point interfaces. A sample
+configuration looks like this:
+
+\begin{Verbatim}
+config wifi-device      "wlan0"
+    option type                "mac80211"
+    option channel      "5"
+
+config wifi-iface
+    option device       "wlan0"
+    option network     lan
+    option mode         "mesh"
+    option mesh_id     "OpenWrt"
+\end{Verbatim}
+
+\paragraph{Wireless Distribution System}
+
+WDS is a non-standard mode which will be working between two Broadcom devices for instance
+but not between a Broadcom and Atheros device.
+
+\subparagraph{Unencrypted WDS connections}
+
+This configuration example shows you how to setup unencrypted WDS connections.
+We assume that the peer configured as below as the BSSID ca:fe:ba:be:00:01
+and the remote WDS endpoint ca:fe:ba:be:00:02 (option bssid field).
+
+\begin{Verbatim}
+config wifi-device      "wl0"
+    option type                "broadcom"
+    option channel      "5"
+
+config wifi-iface
+    option device       "wl0"
+    option network     lan
+    option mode         "ap"
+    option ssid         "OpenWrt"
+    option hidden       "0"
+    option encryption   "none"
+
+config wifi-iface
+    option device       "wl0"
+    option network      lan
+    option mode         wds
+    option ssid         "OpenWrt WDS"
+    option bssid        "ca:fe:ba:be:00:02"
+\end{Verbatim}
+
+\subparagraph{Encrypted WDS connections}
+
+It is also possible to encrypt WDS connections. \texttt{psk}, \texttt{psk2} and
+\texttt{psk+psk2} modes are supported. Configuration below is an example
+configuration using Pre-Shared-Keys with AES algorithm.
+
+\begin{Verbatim}
+config wifi-device  wl0
+    option type     broadcom
+    option channel  5
+
+config wifi-iface
+    option device   "wl0"
+    option network  lan
+    option mode     ap
+    option ssid     "OpenWrt"
+    option encryption  psk2
+    option key      "<key for clients>"
+
+config wifi-iface
+    option device   "wl0"
+    option network  lan
+    option mode     wds
+    option bssid    ca:fe:ba:be:00:02
+    option ssid     "OpenWrt WDS"
+    option encryption  psk2
+    option key      "<psk for WDS>"
+\end{Verbatim}
+
+\paragraph{802.1x configurations}
+
+OpenWrt supports both 802.1x client and Access Point
+configurations. 802.1x client is only working with
+drivers supported by wpa-supplicant. Configuration
+only supports EAP types TLS, TTLS or PEAP.
+
+\subparagraph{EAP-TLS}
+
+\begin{Verbatim}
+config wifi-iface
+    option device         "ath0"
+    option network        lan
+    option ssid           OpenWrt
+    option eap_type       tls
+    option ca_cert        "/etc/config/certs/ca.crt"
+    option priv_key       "/etc/config/certs/priv.crt"
+    option priv_key_pwd   "PKCS#12 passphrase"
+\end{Verbatim}
+
+\subparagraph{EAP-PEAP}
+
+\begin{Verbatim}
+config wifi-iface
+    option device         "ath0"
+    option network        lan
+    option ssid           OpenWrt
+    option eap_type       peap
+    option ca_cert        "/etc/config/certs/ca.crt"
+    option auth           MSCHAPV2
+    option identity       username
+    option password       password
+\end{Verbatim}
+

 \paragraph{Limitations:}
 
 \paragraph{Limitations:}
 

+There are certain limitations when combining modes.

 Only the following mode combinations are supported:
 
 \begin{itemize}
 Only the following mode combinations are supported:
 
 \begin{itemize}


@@ -115,18 +374,119 @@ Only the following mode combinations are supported:
             \item 1x \texttt{sta}, 0-3x \texttt{ap}
             \item 1-4x \texttt{ap}
             \item 1x \texttt{adhoc}
             \item 1x \texttt{sta}, 0-3x \texttt{ap}
             \item 1-4x \texttt{ap}
             \item 1x \texttt{adhoc}

+            \item 1x \texttt{monitor}

         \end{itemize}
 
         \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}: \\
         \begin{itemize}
         settings with the master interface, which is done automatically).
 
     \item \textbf{Atheros}: \\
         \begin{itemize}

-            \item 1x \texttt{sta}, 0-4x \texttt{ap}
-            \item 1-4x \texttt{ap}
+            \item 1x \texttt{sta}, 0-Nx \texttt{ap}
+            \item 1-Nx \texttt{ap}

             \item 1x \texttt{adhoc}
         \end{itemize}
 
             \item 1x \texttt{adhoc}
         \end{itemize}
 

+       N is the maximum number of VAPs that the module allows, it defaults to 4, but can be
+       changed by loading the module with the maxvaps=N parameter.
+\end{itemize}
+
+\paragraph{Adding a new driver configuration}
+
+Since we currently only support thread different wireless drivers : Broadcom, Atheros and mac80211,
+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}
 
 \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}