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> [join]
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 The optional "join" parameter can be used to indicate that this command
114 is requesting an already running GO to prepare for a new client. This is
115 mainly used with "display" to request it to display a PIN.
117 p2p_connect <peer device address> <pbc|pin|PIN#> [display|keypad]
118 [persistent] [join|auth] [go_intent=<0..15>] [freq=<in MHz>]
120 Start P2P group formation with a discovered P2P peer. This includes
121 optional group owner negotiation, group interface setup, provisioning,
122 and establishing data connection.
124 The <pbc|pin|PIN#> parameter specifies the WPS provisioning
125 method. "pbc" string starts pushbutton method, "pin" string start PIN
126 method using an automatically generated PIN (which will be returned as
127 the command return code), PIN# means that a pre-selected PIN can be
128 used (e.g., 12345670). [display|keypad] is used with PIN method
129 to specify which PIN is used (display=dynamically generated random PIN
130 from local display, keypad=PIN entered from peer display). "persistent"
131 parameter can be used to request a persistent group to be formed.
133 "join" indicates that this is a command to join an existing group as a
134 client. It skips the GO Negotiation part. This will send a Provision
135 Discovery Request message to the target GO before associating for WPS
138 "auth" indicates that the WPS parameters are authorized for the peer
139 device without actually starting GO Negotiation (i.e., the peer is
140 expected to initiate GO Negotiation). This is mainly for testing
143 "go_intent" can be used to override the default GO Intent for this GO
146 "freq" can be used to set a forced operating channel (e.g., freq=2412
147 to select 2.4 GHz channel 1).
149 p2p_group_add [persistent|persistent=<network id>] [freq=<freq in MHz>]
151 Set up a P2P group owner manually (i.e., without group owner
152 negotiation with a specific peer). This is also known as autonomous
153 GO. Optional persistent=<network id> can be used to specify restart of
154 a persistent group. Optional freq=<freq in MHz> can be used to force
155 the GO to be started on a specific frequency. Special freq=2 or freq=5
156 options can be used to request the best 2.4 GHz or 5 GHz band channel
157 to be selected automatically.
159 p2p_reject <peer device address>
161 Reject connection attempt from a peer (specified with a device
162 address). This is a mechanism to reject a pending GO Negotiation with
163 a peer and request to automatically block any further connection or
164 discovery of the peer.
166 p2p_group_remove <group interface>
168 Terminate a P2P group. If a new virtual network interface was used for
169 the group, it will also be removed. The network interface name of the
170 group interface is used as a parameter for this command.
174 Cancel an ongoing P2P group formation related operation.
180 Schedule a P2P service discovery request. The parameters for this
181 command are the device address of the peer device (or 00:00:00:00:00:00
182 for wildcard query that is sent to every discovered P2P peer that
183 supports service discovery) and P2P Service Query TLV(s) as hexdump. For
186 p2p_serv_disc_req 00:00:00:00:00:00 02000001
188 schedules a request for listing all available services of all service
189 discovery protocols and requests this to be sent to all discovered
190 peers (note: this can result in long response frames). The pending
191 requests are sent during device discovery (see p2p_find).
193 Only a single pending wildcard query is supported, but there can be
194 multiple pending peer device specific queries (each will be sent in
195 sequence whenever the peer is found).
197 This command returns an identifier for the pending query (e.g.,
198 "1f77628") that can be used to cancel the request. Directed requests
199 will be automatically removed when the specified peer has replied to
202 For UPnP, an alternative command format can be used to specify a
203 single query TLV (i.e., a service discovery for a specific UPnP
206 p2p_serv_disc_req 00:00:00:00:00:00 upnp <version hex> <ST: from M-SEARCH>
210 p2p_serv_disc_req 00:00:00:00:00:00 upnp 10 urn:schemas-upnp-org:device:InternetGatewayDevice:1
212 Additional examples for queries:
214 # list of all Bonjour services
215 p2p_serv_disc_req 00:00:00:00:00:00 02000101
217 # list of all UPnP services
218 p2p_serv_disc_req 00:00:00:00:00:00 02000201
220 # list of all WS-Discovery services
221 p2p_serv_disc_req 00:00:00:00:00:00 02000301
223 # list of all Bonjour and UPnP services
224 p2p_serv_disc_req 00:00:00:00:00:00 0200010102000202
226 # Apple File Sharing over TCP
227 p2p_serv_disc_req 00:00:00:00:00:00 130001010b5f6166706f766572746370c00c000c01
229 # Bonjour SSTH (supported service type hash)
230 p2p_serv_disc_req 00:00:00:00:00:00 05000101000000
233 p2p_serv_disc_req 00:00:00:00:00:00 upnp 10 ssdp:all
234 p2p_serv_disc_req 00:00:00:00:00:00 upnp 10 upnp:rootdevice
235 p2p_serv_disc_req 00:00:00:00:00:00 upnp 10 urn:schemas-upnp-org:service:ContentDirectory:2
236 p2p_serv_disc_req 00:00:00:00:00:00 upnp 10 uuid:6859dede-8574-59ab-9332-123456789012
237 p2p_serv_disc_req 00:00:00:00:00:00 upnp 10 urn:schemas-upnp-org:device:InternetGatewayDevice:1
239 p2p_serv_disc_cancel_req <query identifier>
241 Cancel a pending P2P service discovery request. This command takes a
242 single parameter: identifier for the pending query (the value returned
243 by p2p_serv_disc_req, e.g., "p2p_serv_disc_cancel_req 1f77628".
247 Reply to a service discovery query. This command takes following
248 parameters: frequency in MHz, destination address, dialog token,
249 response TLV(s). The first three parameters are copied from the
250 request event. For example, "p2p_serv_disc_resp 2437 02:40:61:c2:f3:b7
251 1 0300000101". This command is used only if external program is used
252 to process the request (see p2p_serv_disc_external).
256 Indicate that local services have changed. This is used to increment
257 the P2P service indicator value so that peers know when previously
258 cached information may have changed. This is only needed when external
259 service discovery processing is enabled since the commands to
260 pre-configure services for internal processing will increment the
261 indicator automatically.
263 p2p_serv_disc_external <0|1>
265 Configure external processing of P2P service requests: 0 (default) =
266 no external processing of requests (i.e., internal code will process
267 each request based on pre-configured services), 1 = external
268 processing of requests (external program is responsible for replying
269 to service discovery requests with p2p_serv_disc_resp). Please note
270 that there is quite strict limit on how quickly the response needs to
271 be transmitted, so use of the internal processing is strongly
274 p2p_service_add bonjour <query hexdump> <RDATA hexdump>
276 Add a local Bonjour service for internal SD query processing.
281 p2p_service_add bonjour 0b5f6166706f766572746370c00c000c01 074578616d706c65c027
282 # AFP Over TCP (TXT) (RDATA=null)
283 p2p_service_add bonjour 076578616d706c650b5f6166706f766572746370c00c001001 00
285 # IP Printing over TCP (PTR) (RDATA=MyPrinter._ipp._tcp.local.)
286 p2p_service_add bonjour 045f697070c00c000c01 094d795072696e746572c027
287 # IP Printing over TCP (TXT) (RDATA=txtvers=1,pdl=application/postscript)
288 p2p_service_add bonjour 096d797072696e746572045f697070c00c001001 09747874766572733d311a70646c3d6170706c69636174696f6e2f706f7374736372797074
290 # Supported Service Type Hash (SSTH)
291 p2p_service_add bonjour 000000 <32-byte bitfield as hexdump>
292 (note: see P2P spec Annex E.4 for information on how to construct the bitfield)
294 p2p_service_del bonjour <query hexdump>
296 Remove a local Bonjour service from internal SD query processing.
298 p2p_service_add upnp <version hex> <service>
300 Add a local UPnP service for internal SD query processing.
304 p2p_service_add upnp 10 uuid:6859dede-8574-59ab-9332-123456789012::upnp:rootdevice
305 p2p_service_add upnp 10 uuid:5566d33e-9774-09ab-4822-333456785632::upnp:rootdevice
306 p2p_service_add upnp 10 uuid:1122de4e-8574-59ab-9322-333456789044::urn:schemas-upnp-org:service:ContentDirectory:2
307 p2p_service_add upnp 10 uuid:5566d33e-9774-09ab-4822-333456785632::urn:schemas-upnp-org:service:ContentDirectory:2
308 p2p_service_add upnp 10 uuid:6859dede-8574-59ab-9332-123456789012::urn:schemas-upnp-org:device:InternetGatewayDevice:1
310 p2p_service_del upnp <version hex> <service>
312 Remove a local UPnP service from internal SD query processing.
316 Remove all local services from internal SD query processing.
320 p2p_invite [persistent=<network id>|group=<group ifname>] [peer=address]
321 [go_dev_addr=address]
323 Invite a peer to join a group (e.g., group=wlan1) or to reinvoke a
324 persistent group (e.g., persistent=4). If the peer device is the GO of
325 the persisten group, the peer parameter is not needed. Otherwise it is
326 used to specify which device to invite. go_dev_addr parameter can be
327 used to override the GO device address for Invitation Request should
328 it be not known for some reason (this should not be needed in most
333 (These are used on the group interface.)
335 wps_pin <any|address> <PIN>
337 Start WPS PIN method. This allows a single WPS Enrollee to connect to
338 the AP/GO. This is used on the GO when a P2P client joins an existing
339 group. The second parameter is the address of the Enrollee or a string
340 "any" to allow any station to use the entered PIN (which will restrict
341 the PIN for one-time-use). PIN is the Enrollee PIN read either from a
342 label or display on the P2P Client/WPS Enrollee.
346 Start WPS PBC method (i.e., push the button). This allows a single WPS
347 Enrollee to connect to the AP/GO. This is used on the GO when a P2P
348 client joins an existing group.
352 Get the passphrase for a group (only available when acting as a GO).
354 p2p_presence_req [<duration> <interval>] [<duration> <interval>]
356 Send a P2P Presence Request to the GO (this is only available when
357 acting as a P2P client). If no duration/interval pairs are given, the
358 request indicates that this client has no special needs for GO
359 presence. the first parameter pair gives the preferred duration and
360 interval values in microseconds. If the second pair is included, that
361 indicates which value would be acceptable.
365 p2p_ext_listen [<period> <interval>]
367 Configure Extended Listen Timing. If the parameters are omitted, this
368 feature is disabled. If the parameters are included, Listen State will
369 be entered every interval msec for at least period msec. Both values
370 have acceptable range of 1-65535 (with interval obviously having to be
371 larger than or equal to duration). If the P2P module is not idle at
372 the time the Extended Listen Timing timeout occurs, the Listen State
373 operation will be skipped.
375 The configured values will also be advertised to other P2P Devices. The
376 received values are available in the p2p_peer command output:
378 ext_listen_period=100 ext_listen_interval=5000
380 p2p_set <field> <value>
382 Change dynamic P2P parameters
384 p2p_set discoverability <0/1>
386 Disable/enable advertisement of client discoverability. This is
387 enabled by default and this parameter is mainly used to allow testing
388 of device discoverability.
390 p2p_set managed <0/1>
392 Disable/enable managed P2P Device operations. This is disabled by
395 p2p_set listen_channel <1/6/11>
397 Set P2P Listen channel. This is mainly meant for testing purposes and
398 changing the Listen channel during normal operations can result in
401 p2p_set ssid_postfix <postfix>
403 Set postfix string to be added to the automatically generated P2P SSID
404 (DIRECT-<two random characters>). For example, postfix of "-testing"
405 could result in the SSID becoming DIRECT-ab-testing.
409 Set global configuration parameters which may also affect P2P
410 operations. The format on these parameters is same as is used in
411 wpa_supplicant.conf. Only the parameters listen here should be
412 changed. Modifying other parameters may result in incorrect behavior
413 since not all existing users of the parameters are updated.
417 Set WPS UUID (by default, this is generated based on the MAC address).
419 set device_name <device name>
421 Set WPS Device Name (also included in some P2P messages).
423 set manufacturer <manufacturer>
425 Set WPS Manufacturer.
427 set model_name <model name>
431 set model_number <model number>
433 Set WPS Model Number.
435 set serial_number <serial number>
437 Set WPS Serial Number.
439 set device_type <device type>
443 set os_version <OS version>
447 set config_methods <config methods>
449 Set WPS Configuration Methods.
451 set sec_device_type <device type>
453 Add a new Secondary Device Type.
455 set p2p_go_intent <GO intent>
457 Set the default P2P GO Intent. Note: This value can be overridden in
458 p2p_connect command and as such, there should be no need to change the
459 default value here during normal operations.
461 set p2p_ssid_postfix <P2P SSID postfix>
463 Set P2P SSID postfix.
465 set persistent_reconnect <0/1>
467 Disable/enabled persistent reconnect for reinvocation of persistent
468 groups. If enabled, invitations to reinvoke a persistent group will be
469 accepted without separate authorization (e.g., user interaction).
471 set country <two character country code>
473 Set country code (this is included in some P2P messages).
477 p2p_peers [discovered]
479 List P2P Device Addresses of all the P2P peers we know. The optional
480 "discovered" parameter filters out the peers that we have not fully
481 discovered, i.e., which we have only seen in a received Probe Request
484 p2p_peer <P2P Device Address>
486 Fetch information about a known P2P peer.
490 (These are used on the group interface.)
494 Show status information (connection state, role, use encryption
495 parameters, IP address, etc.).
499 Show information about an associated station (when acting in AP/GO role).
503 Lists the currently associated stations.
509 Lists the configured networks, including stored information for
510 persistent groups. The identifier in this list is used with
511 p2p_group_add and p2p_invite to indicate which persistent group is to
514 remove_network <network id>
516 Remove a network entry from configuration.
519 wpa_cli action script
520 ---------------------
522 See examples/p2p-action.sh
524 TODO: describe DHCP/DNS setup
525 TODO: cross-connection