1 wpa_supplicant and Wi-Fi P2P
2 ============================
4 This document describes how the Wi-Fi P2P implementation in
5 wpa_supplicant can be configured and how an external component on the
6 client (e.g., management GUI) is used to enable WPS enrollment and
7 registrar registration.
10 Introduction to Wi-Fi P2P
11 -------------------------
15 More information about Wi-Fi P2P is available from Wi-Fi Alliance:
16 http://www.wi-fi.org/Wi-Fi_Direct.php
19 wpa_supplicant implementation
20 -----------------------------
25 wpa_supplicant configuration
26 ----------------------------
28 Wi-Fi P2P is an optional component that needs to be enabled in the
29 wpa_supplicant build configuration (.config). Here is an example
30 configuration that includes Wi-Fi P2P support and Linux nl80211
31 -based driver interface:
33 CONFIG_DRIVER_NL80211=y
40 In run-time configuration file (wpa_supplicant.conf), some parameters
41 for P2P may be set. In order to make the devices easier to recognize,
42 device_name and device_type should be specified. For example,
43 something like this should be included:
45 ctrl_interface=/var/run/wpa_supplicant
46 device_name=My P2P Device
47 device_type=1-0050F204-1
53 Actual Wi-Fi P2P operations are requested during runtime. These can be
54 done for example using wpa_cli (which is described below) or a GUI
58 wpa_cli starts in interactive mode if no command string is included on
59 the command line. By default, it will select the first network interface
60 that it can find (and that wpa_supplicant controls). If more than one
61 interface is in use, it may be necessary to select one of the explicitly
62 by adding -i argument on the command line (e.g., 'wpa_cli -i wlan1').
64 Most of the P2P operations are done on the main interface (e.g., the
65 interface that is automatically added when the driver is loaded, e.g.,
66 wlan0). When using a separate virtual interface for group operations
67 (e.g., wlan1), the control interface for that group interface may need
68 to be used for some operations (mainly WPS activation in GO). This may
69 change in the future so that all the needed operations could be done
70 over the main control interface.
74 p2p_find [timeout in seconds] [type=<social|progressive>]
76 The default behavior is to run a single full scan in the beginning and
77 then scan only social channels. type=social will scan only social
78 channels, i.e., it skips the initial full scan. type=progressive is
79 like the default behavior, but it will scan through all the channels
80 progressively one channel at the time in the Search state rounds. This
81 will help in finding new groups or groups missed during the initial
84 p2p_listen [timeout in seconds]
86 Start Listen-only state (become discoverable without searching for
87 other devices). Optional parameter can be used to specify the duration
88 for the Listen operation in seconds. This command may not be of that
89 much use during normal operations and is mainly designed for
90 testing. It can also be used to keep the device discoverable without
91 having to maintain a group.
95 Stop ongoing P2P device discovery or other operation (connect, listen
100 Flush P2P peer table and state.
104 p2p_prov_disc <peer device address> <display|keypad|pbc>
106 Send P2P provision discovery request to the specified peer. The
107 parameters for this command are the P2P device address of the peer and
108 the desired configuration method. For example, "p2p_prov_disc
109 02:01:02:03:04:05 display" would request the peer to display a PIN for
110 us and "p2p_prov_disc 02:01:02:03:04:05 keypad" would request the peer
111 to enter a PIN that we display.
113 p2p_connect <peer device address> <pbc|pin|PIN#> [display|keypad]
114 [persistent] [join|auth] [go_intent=<0..15>] [freq=<in MHz>]
116 Start P2P group formation with a discovered P2P peer. This includes
117 optional group owner negotiation, group interface setup, provisioning,
118 and establishing data connection.
120 The <pbc|pin|PIN#> parameter specifies the WPS provisioning
121 method. "pbc" string starts pushbutton method, "pin" string start PIN
122 method using an automatically generated PIN (which will be returned as
123 the command return code), PIN# means that a pre-selected PIN can be
124 used (e.g., 12345670). [display|keypad] is used with PIN method
125 to specify which PIN is used (display=dynamically generated random PIN
126 from local display, keypad=PIN entered from peer display). "persistent"
127 parameter can be used to request a persistent group to be formed.
129 "join" indicates that this is a command to join an existing group as a
130 client. It skips the GO Negotiation part. This will send a Provision
131 Discovery Request message to the target GO before associating for WPS
134 "auth" indicates that the WPS parameters are authorized for the peer
135 device without actually starting GO Negotiation (i.e., the peer is
136 expected to initiate GO Negotiation). This is mainly for testing
139 "go_intent" can be used to override the default GO Intent for this GO
142 "freq" can be used to set a forced operating channel (e.g., freq=2412
143 to select 2.4 GHz channel 1).
145 p2p_group_add [persistent|persistent=<network id>] [freq=<freq in MHz>]
147 Set up a P2P group owner manually (i.e., without group owner
148 negotiation with a specific peer). This is also known as autonomous
149 GO. Optional persistent=<network id> can be used to specify restart of
150 a persistent group. Optional freq=<freq in MHz> can be used to force
151 the GO to be started on a specific frequency. Special freq=2 or freq=5
152 options can be used to request the best 2.4 GHz or 5 GHz band channel
153 to be selected automatically.
155 p2p_reject <peer device address>
157 Reject connection attempt from a peer (specified with a device
158 address). This is a mechanism to reject a pending GO Negotiation with
159 a peer and request to automatically block any further connection or
160 discovery of the peer.
162 p2p_group_remove <group interface>
164 Terminate a P2P group. If a new virtual network interface was used for
165 the group, it will also be removed. The network interface name of the
166 group interface is used as a parameter for this command.
170 Cancel an ongoing P2P group formation related operation.
176 Schedule a P2P service discovery request. The parameters for this
177 command are the device address of the peer device (or 00:00:00:00:00:00
178 for wildcard query that is sent to every discovered P2P peer that
179 supports service discovery) and P2P Service Query TLV(s) as hexdump. For
182 p2p_serv_disc_req 00:00:00:00:00:00 02000001
184 schedules a request for listing all available services of all service
185 discovery protocols and requests this to be sent to all discovered
186 peers (note: this can result in long response frames). The pending
187 requests are sent during device discovery (see p2p_find).
189 Only a single pending wildcard query is supported, but there can be
190 multiple pending peer device specific queries (each will be sent in
191 sequence whenever the peer is found).
193 This command returns an identifier for the pending query (e.g.,
194 "1f77628") that can be used to cancel the request. Directed requests
195 will be automatically removed when the specified peer has replied to
198 For UPnP, an alternative command format can be used to specify a
199 single query TLV (i.e., a service discovery for a specific UPnP
202 p2p_serv_disc_req 00:00:00:00:00:00 upnp <version hex> <ST: from M-SEARCH>
206 p2p_serv_disc_req 00:00:00:00:00:00 upnp 10 urn:schemas-upnp-org:device:InternetGatewayDevice:1
208 Additional examples for queries:
210 # list of all Bonjour services
211 p2p_serv_disc_req 00:00:00:00:00:00 02000101
213 # list of all UPnP services
214 p2p_serv_disc_req 00:00:00:00:00:00 02000201
216 # list of all WS-Discovery services
217 p2p_serv_disc_req 00:00:00:00:00:00 02000301
219 # list of all Bonjour and UPnP services
220 p2p_serv_disc_req 00:00:00:00:00:00 0200010102000202
222 # Apple File Sharing over TCP
223 p2p_serv_disc_req 00:00:00:00:00:00 130001010b5f6166706f766572746370c00c000c01
225 # Bonjour SSTH (supported service type hash)
226 p2p_serv_disc_req 00:00:00:00:00:00 05000101000000
229 p2p_serv_disc_req 00:00:00:00:00:00 upnp 10 ssdp:all
230 p2p_serv_disc_req 00:00:00:00:00:00 upnp 10 upnp:rootdevice
231 p2p_serv_disc_req 00:00:00:00:00:00 upnp 10 urn:schemas-upnp-org:service:ContentDirectory:2
232 p2p_serv_disc_req 00:00:00:00:00:00 upnp 10 uuid:6859dede-8574-59ab-9332-123456789012
233 p2p_serv_disc_req 00:00:00:00:00:00 upnp 10 urn:schemas-upnp-org:device:InternetGatewayDevice:1
235 p2p_serv_disc_cancel_req <query identifier>
237 Cancel a pending P2P service discovery request. This command takes a
238 single parameter: identifier for the pending query (the value returned
239 by p2p_serv_disc_req, e.g., "p2p_serv_disc_cancel_req 1f77628".
243 Reply to a service discovery query. This command takes following
244 parameters: frequency in MHz, destination address, dialog token,
245 response TLV(s). The first three parameters are copied from the
246 request event. For example, "p2p_serv_disc_resp 2437 02:40:61:c2:f3:b7
247 1 0300000101". This command is used only if external program is used
248 to process the request (see p2p_serv_disc_external).
252 Indicate that local services have changed. This is used to increment
253 the P2P service indicator value so that peers know when previously
254 cached information may have changed. This is only needed when external
255 service discovery processing is enabled since the commands to
256 pre-configure services for internal processing will increment the
257 indicator automatically.
259 p2p_serv_disc_external <0|1>
261 Configure external processing of P2P service requests: 0 (default) =
262 no external processing of requests (i.e., internal code will process
263 each request based on pre-configured services), 1 = external
264 processing of requests (external program is responsible for replying
265 to service discovery requests with p2p_serv_disc_resp). Please note
266 that there is quite strict limit on how quickly the response needs to
267 be transmitted, so use of the internal processing is strongly
270 p2p_service_add bonjour <query hexdump> <RDATA hexdump>
272 Add a local Bonjour service for internal SD query processing.
277 p2p_service_add bonjour 0b5f6166706f766572746370c00c000c01 074578616d706c65c027
278 # AFP Over TCP (TXT) (RDATA=null)
279 p2p_service_add bonjour 076578616d706c650b5f6166706f766572746370c00c001001 00
281 # IP Printing over TCP (PTR) (RDATA=MyPrinter._ipp._tcp.local.)
282 p2p_service_add bonjour 045f697070c00c000c01 094d795072696e746572c027
283 # IP Printing over TCP (TXT) (RDATA=txtvers=1,pdl=application/postscript)
284 p2p_service_add bonjour 096d797072696e746572045f697070c00c001001 09747874766572733d311a70646c3d6170706c69636174696f6e2f706f7374736372797074
286 # Supported Service Type Hash (SSTH)
287 p2p_service_add bonjour 000000 <32-byte bitfield as hexdump>
288 (note: see P2P spec Annex E.4 for information on how to construct the bitfield)
290 p2p_service_del bonjour <query hexdump>
292 Remove a local Bonjour service from internal SD query processing.
294 p2p_service_add upnp <version hex> <service>
296 Add a local UPnP service for internal SD query processing.
300 p2p_service_add upnp 10 uuid:6859dede-8574-59ab-9332-123456789012::upnp:rootdevice
301 p2p_service_add upnp 10 uuid:5566d33e-9774-09ab-4822-333456785632::upnp:rootdevice
302 p2p_service_add upnp 10 uuid:1122de4e-8574-59ab-9322-333456789044::urn:schemas-upnp-org:service:ContentDirectory:2
303 p2p_service_add upnp 10 uuid:5566d33e-9774-09ab-4822-333456785632::urn:schemas-upnp-org:service:ContentDirectory:2
304 p2p_service_add upnp 10 uuid:6859dede-8574-59ab-9332-123456789012::urn:schemas-upnp-org:device:InternetGatewayDevice:1
306 p2p_service_del upnp <version hex> <service>
308 Remove a local UPnP service from internal SD query processing.
312 Remove all local services from internal SD query processing.
316 p2p_invite [persistent=<network id>|group=<group ifname>] [peer=address]
317 [go_dev_addr=address]
319 Invite a peer to join a group (e.g., group=wlan1) or to reinvoke a
320 persistent group (e.g., persistent=4). If the peer device is the GO of
321 the persisten group, the peer parameter is not needed. Otherwise it is
322 used to specify which device to invite. go_dev_addr parameter can be
323 used to override the GO device address for Invitation Request should
324 it be not known for some reason (this should not be needed in most
329 (These are used on the group interface.)
331 wps_pin <any|address> <PIN>
333 Start WPS PIN method. This allows a single WPS Enrollee to connect to
334 the AP/GO. This is used on the GO when a P2P client joins an existing
335 group. The second parameter is the address of the Enrollee or a string
336 "any" to allow any station to use the entered PIN (which will restrict
337 the PIN for one-time-use). PIN is the Enrollee PIN read either from a
338 label or display on the P2P Client/WPS Enrollee.
342 Start WPS PBC method (i.e., push the button). This allows a single WPS
343 Enrollee to connect to the AP/GO. This is used on the GO when a P2P
344 client joins an existing group.
348 Get the passphrase for a group (only available when acting as a GO).
350 p2p_presence_req [<duration> <interval>] [<duration> <interval>]
352 Send a P2P Presence Request to the GO (this is only available when
353 acting as a P2P client). If no duration/interval pairs are given, the
354 request indicates that this client has no special needs for GO
355 presence. the first parameter pair gives the preferred duration and
356 interval values in microseconds. If the second pair is included, that
357 indicates which value would be acceptable.
361 p2p_ext_listen [<period> <interval>]
363 Configure Extended Listen Timing. If the parameters are omitted, this
364 feature is disabled. If the parameters are included, Listen State will
365 be entered every interval msec for at least period msec. Both values
366 have acceptable range of 1-65535 (with interval obviously having to be
367 larger than or equal to duration). If the P2P module is not idle at
368 the time the Extended Listen Timing timeout occurs, the Listen State
369 operation will be skipped.
371 The configured values will also be advertised to other P2P Devices. The
372 received values are available in the p2p_peer command output:
374 ext_listen_period=100 ext_listen_interval=5000
376 p2p_set <field> <value>
378 Change dynamic P2P parameters
380 p2p_set discoverability <0/1>
382 Disable/enable advertisement of client discoverability. This is
383 enabled by default and this parameter is mainly used to allow testing
384 of device discoverability.
386 p2p_set managed <0/1>
388 Disable/enable managed P2P Device operations. This is disabled by
391 p2p_set listen_channel <1/6/11>
393 Set P2P Listen channel. This is mainly meant for testing purposes and
394 changing the Listen channel during normal operations can result in
397 p2p_set ssid_postfix <postfix>
399 Set postfix string to be added to the automatically generated P2P SSID
400 (DIRECT-<two random characters>). For example, postfix of "-testing"
401 could result in the SSID becoming DIRECT-ab-testing.
405 Set global configuration parameters which may also affect P2P
406 operations. The format on these parameters is same as is used in
407 wpa_supplicant.conf. Only the parameters listen here should be
408 changed. Modifying other parameters may result in incorrect behavior
409 since not all existing users of the parameters are updated.
413 Set WPS UUID (by default, this is generated based on the MAC address).
415 set device_name <device name>
417 Set WPS Device Name (also included in some P2P messages).
419 set manufacturer <manufacturer>
421 Set WPS Manufacturer.
423 set model_name <model name>
427 set model_number <model number>
429 Set WPS Model Number.
431 set serial_number <serial number>
433 Set WPS Serial Number.
435 set device_type <device type>
439 set os_version <OS version>
443 set config_methods <config methods>
445 Set WPS Configuration Methods.
447 set sec_device_type <device type>
449 Add a new Secondary Device Type.
451 set p2p_go_intent <GO intent>
453 Set the default P2P GO Intent. Note: This value can be overridden in
454 p2p_connect command and as such, there should be no need to change the
455 default value here during normal operations.
457 set p2p_ssid_postfix <P2P SSID postfix>
459 Set P2P SSID postfix.
461 set persistent_reconnect <0/1>
463 Disable/enabled persistent reconnect for reinvocation of persistent
464 groups. If enabled, invitations to reinvoke a persistent group will be
465 accepted without separate authorization (e.g., user interaction).
467 set country <two character country code>
469 Set country code (this is included in some P2P messages).
473 p2p_peers [discovered]
475 List P2P Device Addresses of all the P2P peers we know. The optional
476 "discovered" parameter filters out the peers that we have not fully
477 discovered, i.e., which we have only seen in a received Probe Request
480 p2p_peer <P2P Device Address>
482 Fetch information about a known P2P peer.
486 (These are used on the group interface.)
490 Show status information (connection state, role, use encryption
491 parameters, IP address, etc.).
495 Show information about an associated station (when acting in AP/GO role).
499 Lists the currently associated stations.
505 Lists the configured networks, including stored information for
506 persistent groups. The identifier in this list is used with
507 p2p_group_add and p2p_invite to indicate which persistent group is to
510 remove_network <network id>
512 Remove a network entry from configuration.
515 wpa_cli action script
516 ---------------------
518 See examples/p2p-action.sh
520 TODO: describe DHCP/DNS setup
521 TODO: cross-connection