mac80211: add initial support for AR9330
[openwrt/svn-archive/archive.git] / docs / wireless.tex
1 The WiFi settings are configured in the file \texttt{/etc/config/wireless}
2 (currently supported on Broadcom, Atheros and mac80211). When booting the router for the first time
3 it should detect your card and create a sample configuration file. By default '\texttt{option network lan}' is
4 commented. This prevents unsecured sharing of the network over the wireless interface.
5
6 Each wireless driver has its own configuration script in \texttt{/lib/wifi/driver\_name.sh} which handles
7 driver specific options and configurations. This script is also calling driver specific binaries like wlc for
8 Broadcom, or hostapd and wpa\_supplicant for atheros and mac80211.
9
10 The reason for using such architecture, is that it abstracts the driver configuration.
11
12 \paragraph{Generic Broadcom wireless config:}
13
14 \begin{Verbatim}
15 config wifi-device "wl0"
16 option type "broadcom"
17 option channel "5"
18
19 config wifi-iface
20 option device "wl0"
21 # option network lan
22 option mode "ap"
23 option ssid "OpenWrt"
24 option hidden "0"
25 option encryption "none"
26 \end{Verbatim}
27
28 \paragraph{Generic Atheros wireless config:}
29
30 \begin{Verbatim}
31 config wifi-device "wifi0"
32 option type "atheros"
33 option channel "5"
34 option hwmode "11g"
35
36 config wifi-iface
37 option device "wifi0"
38 # option network lan
39 option mode "ap"
40 option ssid "OpenWrt"
41 option hidden "0"
42 option encryption "none"
43 \end{Verbatim}
44
45 \paragraph{Generic mac80211 wireless config:}
46
47 \begin{Verbatim}
48 config wifi-device "wifi0"
49 option type "mac80211"
50 option channel "5"
51
52 config wifi-iface
53 option device "wlan0"
54 # option network lan
55 option mode "ap"
56 option ssid "OpenWrt"
57 option hidden "0"
58 option encryption "none"
59 \end{Verbatim}
60
61 \paragraph{Generic multi-radio Atheros wireless config:}
62
63 \begin{Verbatim}
64 config wifi-device wifi0
65 option type atheros
66 option channel 1
67
68 config wifi-iface
69 option device wifi0
70 # option network lan
71 option mode ap
72 option ssid OpenWrt_private
73 option hidden 0
74 option encryption none
75
76 config wifi-device wifi1
77 option type atheros
78 option channel 11
79
80 config wifi-iface
81 option device wifi1
82 # option network lan
83 option mode ap
84 option ssid OpenWrt_public
85 option hidden 1
86 option encryption none
87 \end{Verbatim}
88
89 There are two types of config sections in this file. The '\texttt{wifi-device}' refers to
90 the physical wifi interface and '\texttt{wifi-iface}' configures a virtual interface on top
91 of that (if supported by the driver).
92
93 A full outline of the wireless configuration file with description of each field:
94
95 \begin{Verbatim}
96 config wifi-device wifi device name
97 option type broadcom, atheros, mac80211
98 option country us, uk, fr, de, etc.
99 option channel 1-14
100 option maxassoc 1-128 (broadcom only)
101 option distance 1-n (meters)
102 option hwmode 11b, 11g, 11a, 11bg (atheros, mac80211)
103 option rxantenna 0,1,2 (atheros, broadcom)
104 option txantenna 0,1,2 (atheros, broadcom)
105 option txpower transmission power in dBm
106
107 config wifi-iface
108 option network the interface you want wifi to bridge with
109 option device wifi0, wifi1, wifi2, wifiN
110 option mode ap, sta, adhoc, monitor, mesh, or wds
111 option txpower (deprecated) transmission power in dBm
112 option ssid ssid name
113 option bssid bssid address
114 option encryption none, wep, psk, psk2, wpa, wpa2
115 option key encryption key
116 option key1 key 1
117 option key2 key 2
118 option key3 key 3
119 option key4 key 4
120 option passphrase 0,1
121 option server ip address
122 option port port
123 option hidden 0,1
124 option isolate 0,1 (broadcom)
125 option doth 0,1 (atheros, broadcom)
126 option wmm 0,1 (atheros, broadcom)
127 \end{Verbatim}
128
129 \paragraph{Options for the \texttt{wifi-device}:}
130
131 \begin{itemize}
132 \item \texttt{type} \\
133 The driver to use for this interface.
134
135 \item \texttt{country} \\
136 The country code used to determine the regulatory settings.
137
138 \item \texttt{channel} \\
139 The wifi channel (e.g. 1-14, depending on your country setting).
140
141 \item \texttt{maxassoc} \\
142 Optional: Maximum number of associated clients. This feature is supported only on the Broadcom chipsets.
143
144 \item \texttt{distance} \\
145 Optional: Distance between the ap and the furthest client in meters. This feature is supported only on the Atheros chipsets.
146
147 \item \texttt{mode} \\
148 The frequency band (\texttt{b}, \texttt{g}, \texttt{bg}, \texttt{a}). This feature is only supported on the Atheros chipsets.
149
150 \item \texttt{diversity} \\
151 Optional: Enable diversity for the Wi-Fi device. This feature is supported only on the Atheros chipsets.
152
153 \item \texttt{rxantenna} \\
154 Optional: Antenna identifier (0, 1 or 2) for reception. This feature is supported by Atheros and some Broadcom chipsets.
155
156 \item \texttt{txantenna} \\
157 Optional: Antenna identifier (0, 1 or 2) for emission. This feature is supported by Atheros and some Broadcom chipsets.
158
159 \item \texttt{txpower}
160 Set the transmission power to be used. The amount is specified in dBm.
161
162 \end{itemize}
163
164 \paragraph{Options for the \texttt{wifi-iface}:}
165
166 \begin{itemize}
167 \item \texttt{network} \\
168 Selects the interface section from \texttt{/etc/config/network} to be
169 used with this interface
170
171 \item \texttt{device} \\
172 Set the wifi device name.
173
174 \item \texttt{mode} \\
175 Operating mode:
176
177 \begin{itemize}
178 \item \texttt{ap} \\
179 Access point mode
180
181 \item \texttt{sta} \\
182 Client mode
183
184 \item \texttt{adhoc} \\
185 Ad-Hoc mode
186
187 \item \texttt{monitor} \\
188 Monitor mode
189
190 \item \texttt{mesh} \\
191 Mesh Point mode (802.11s)
192
193 \item \texttt{wds} \\
194 WDS point-to-point link
195
196 \end{itemize}
197
198 \item \texttt{ssid}
199 Set the SSID to be used on the wifi device.
200
201 \item \texttt{bssid}
202 Set the BSSID address to be used for wds to set the mac address of the other wds unit.
203
204 \item \texttt{txpower}
205 (Deprecated, set in wifi-device) Set the transmission power to be used. The amount is specified in dBm.
206
207 \item \texttt{encryption} \\
208 Encryption setting. Accepts the following values:
209
210 \begin{itemize}
211 \item \texttt{none}
212 \item \texttt{wep}
213 \item \texttt{psk}, \texttt{psk2} \\
214 WPA(2) Pre-shared Key
215
216 \item \texttt{wpa}, \texttt{wpa2} \\
217 WPA(2) RADIUS
218 \end{itemize}
219
220 \item \texttt{key, key1, key2, key3, key4} (wep, wpa and psk) \\
221 WEP key, WPA key (PSK mode) or the RADIUS shared secret (WPA RADIUS mode)
222
223 \item \texttt{passphrase} (wpa) \\
224 0 treats the wpa psk as a text passphrase; 1 treats wpa psk as
225 encoded passphrase. You can generate an encoded passphrase with
226 the wpa\_passphrase utility. This is especially useful if your
227 passphrase contains special characters. This option only works
228 when using mac80211 or atheros type devices.
229
230 \item \texttt{server} (wpa) \\
231 The RADIUS server ip address
232
233 \item \texttt{port} (wpa) \\
234 The RADIUS server port (defaults to 1812)
235
236 \item \texttt{hidden} \\
237 0 broadcasts the ssid; 1 disables broadcasting of the ssid
238
239 \item \texttt{isolate} \\
240 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.
241 0 disables ap isolation (default); 1 enables ap isolation.
242
243 \item \texttt{doth} \\
244 Optional: Toggle 802.11h mode.
245 0 disables 802.11h (default); 1 enables it.
246
247 \item \texttt{wmm} \\
248 Optional: Toggle 802.11e mode.
249 0 disables 802.11e (default); 1 enables it.
250
251 \end{itemize}
252
253 \paragraph{Mesh Point}
254
255 Mesh Point (802.11s) is only supported by some mac80211 drivers. It requires the iw package
256 to be installed to setup mesh links. OpenWrt creates mshN mesh point interfaces. A sample
257 configuration looks like this:
258
259 \begin{Verbatim}
260 config wifi-device "wlan0"
261 option type "mac80211"
262 option channel "5"
263
264 config wifi-iface
265 option device "wlan0"
266 option network lan
267 option mode "mesh"
268 option mesh_id "OpenWrt"
269 \end{Verbatim}
270
271 \paragraph{Wireless Distribution System}
272
273 WDS is a non-standard mode which will be working between two Broadcom devices for instance
274 but not between a Broadcom and Atheros device.
275
276 \subparagraph{Unencrypted WDS connections}
277
278 This configuration example shows you how to setup unencrypted WDS connections.
279 We assume that the peer configured as below as the BSSID ca:fe:ba:be:00:01
280 and the remote WDS endpoint ca:fe:ba:be:00:02 (option bssid field).
281
282 \begin{Verbatim}
283 config wifi-device "wl0"
284 option type "broadcom"
285 option channel "5"
286
287 config wifi-iface
288 option device "wl0"
289 option network lan
290 option mode "ap"
291 option ssid "OpenWrt"
292 option hidden "0"
293 option encryption "none"
294
295 config wifi-iface
296 option device "wl0"
297 option network lan
298 option mode wds
299 option ssid "OpenWrt WDS"
300 option bssid "ca:fe:ba:be:00:02"
301 \end{Verbatim}
302
303 \subparagraph{Encrypted WDS connections}
304
305 It is also possible to encrypt WDS connections. \texttt{psk}, \texttt{psk2} and
306 \texttt{psk+psk2} modes are supported. Configuration below is an example
307 configuration using Pre-Shared-Keys with AES algorithm.
308
309 \begin{Verbatim}
310 config wifi-device wl0
311 option type broadcom
312 option channel 5
313
314 config wifi-iface
315 option device "wl0"
316 option network lan
317 option mode ap
318 option ssid "OpenWrt"
319 option encryption psk2
320 option key "<key for clients>"
321
322 config wifi-iface
323 option device "wl0"
324 option network lan
325 option mode wds
326 option bssid ca:fe:ba:be:00:02
327 option ssid "OpenWrt WDS"
328 option encryption psk2
329 option key "<psk for WDS>"
330 \end{Verbatim}
331
332 \paragraph{802.1x configurations}
333
334 OpenWrt supports both 802.1x client and Access Point
335 configurations. 802.1x client is only working with
336 drivers supported by wpa-supplicant. Configuration
337 only supports EAP types TLS, TTLS or PEAP.
338
339 \subparagraph{EAP-TLS}
340
341 \begin{Verbatim}
342 config wifi-iface
343 option device "ath0"
344 option network lan
345 option ssid OpenWrt
346 option eap_type tls
347 option ca_cert "/etc/config/certs/ca.crt"
348 option priv_key "/etc/config/certs/priv.crt"
349 option priv_key_pwd "PKCS#12 passphrase"
350 \end{Verbatim}
351
352 \subparagraph{EAP-PEAP}
353
354 \begin{Verbatim}
355 config wifi-iface
356 option device "ath0"
357 option network lan
358 option ssid OpenWrt
359 option eap_type peap
360 option ca_cert "/etc/config/certs/ca.crt"
361 option auth MSCHAPV2
362 option identity username
363 option password password
364 \end{Verbatim}
365
366 \paragraph{Limitations:}
367
368 There are certain limitations when combining modes.
369 Only the following mode combinations are supported:
370
371 \begin{itemize}
372 \item \textbf{Broadcom}: \\
373 \begin{itemize}
374 \item 1x \texttt{sta}, 0-3x \texttt{ap}
375 \item 1-4x \texttt{ap}
376 \item 1x \texttt{adhoc}
377 \item 1x \texttt{monitor}
378 \end{itemize}
379
380 WDS links can only be used in pure AP mode and cannot use WEP (except when sharing the
381 settings with the master interface, which is done automatically).
382
383 \item \textbf{Atheros}: \\
384 \begin{itemize}
385 \item 1x \texttt{sta}, 0-Nx \texttt{ap}
386 \item 1-Nx \texttt{ap}
387 \item 1x \texttt{adhoc}
388 \end{itemize}
389
390 N is the maximum number of VAPs that the module allows, it defaults to 4, but can be
391 changed by loading the module with the maxvaps=N parameter.
392 \end{itemize}
393
394 \paragraph{Adding a new driver configuration}
395
396 Since we currently only support thread different wireless drivers : Broadcom, Atheros and mac80211,
397 you might be interested in adding support for another driver like Ralink RT2x00,
398 Texas Instruments ACX100/111.
399
400 The driver specific script should be placed in \texttt{/lib/wifi/<driver>.sh} and has to
401 include several functions providing :
402
403 \begin{itemize}
404 \item detection of the driver presence
405 \item enabling/disabling the wifi interface(s)
406 \item configuration reading and setting
407 \item third-party programs calling (nas, supplicant)
408 \end{itemize}
409
410 Each driver script should append the driver to a global DRIVERS variable :
411
412 \begin{Verbatim}
413 append DRIVERS "driver name"
414 \end{Verbatim}
415
416 \subparagraph{\texttt{scan\_<driver>}}
417
418 This function will parse the \texttt{/etc/config/wireless} and make sure there
419 are no configuration incompatibilities, like enabling hidden SSIDS with ad-hoc mode
420 for instance. This can be more complex if your driver supports a lof of configuration
421 options. It does not change the state of the interface.
422
423 Example:
424 \begin{Verbatim}
425 scan_dummy() {
426 local device="$1"
427
428 config_get vifs "$device" vifs
429 for vif in $vifs; do
430 # check config consistency for wifi-iface sections
431 done
432 # check mode combination
433 }
434 \end{Verbatim}
435
436 \subparagraph{\texttt{enable\_<driver>}}
437
438 This function will bring up the wifi device and optionally create application specific
439 configuration files, e.g. for the WPA authenticator or supplicant.
440
441 Example:
442 \begin{Verbatim}
443 enable_dummy() {
444 local device="$1"
445
446 config_get vifs "$device" vifs
447 for vif in $vifs; do
448 # bring up virtual interface belonging to
449 # the wifi-device "$device"
450 done
451 }
452 \end{Verbatim}
453
454 \subparagraph{\texttt{disable\_<driver>}}
455
456 This function will bring down the wifi device and all its virtual interfaces (if supported).
457
458 Example:
459 \begin{Verbatim}
460 disable_dummy() {
461 local device="$1"
462
463 # bring down virtual interfaces belonging to
464 # "$device" regardless of whether they are
465 # configured or not. Don't rely on the vifs
466 # variable at this point
467 }
468 \end{Verbatim}
469
470 \subparagraph{\texttt{detect\_<driver>}}
471
472 This function looks for interfaces that are usable with the driver. Template config sections
473 for new devices should be written to stdout. Must check for already existing config sections
474 belonging to the interfaces before creating new templates.
475
476 Example:
477 \begin{Verbatim}
478 detect_dummy() {
479 [ wifi-device = "$(config_get dummydev type)" ] && return 0
480 cat <<EOF
481 config wifi-device dummydev
482 option type dummy
483 # REMOVE THIS LINE TO ENABLE WIFI:
484 option disabled 1
485
486 config wifi-iface
487 option device dummydev
488 option mode ap
489 option ssid OpenWrt
490 EOF
491 }
492 \end{Verbatim}