1 wpa_supplicant and Wi-Fi P2P 2 ============================ 3 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. 8 9 10 Introduction to Wi-Fi P2P 11 ------------------------- 12 13 TODO 14 15 More information about Wi-Fi P2P is available from Wi-Fi Alliance: 16 http://www.wi-fi.org/Wi-Fi_Direct.php 17 18 19 wpa_supplicant implementation 20 ----------------------------- 21 22 TODO 23 24 25 wpa_supplicant configuration 26 ---------------------------- 27 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: 32 33 CONFIG_DRIVER_NL80211=y 34 CONFIG_CTRL_IFACE=y 35 CONFIG_P2P=y 36 CONFIG_AP=y 37 CONFIG_WPS=y 38 39 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: 44 45 ctrl_interface=/var/run/wpa_supplicant 46 device_name=My P2P Device 47 device_type=1-0050F204-1 48 49 50 wpa_cli 51 ------- 52 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 55 like wpa_gui-qt4. 56 57 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'). 63 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. 71 72 Device Discovery 73 74 p2p_find [timeout in seconds] [type=<social|progressive>] 75 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 82 full scan. 83 84 p2p_listen [timeout in seconds] 85 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. 92 93 p2p_stop_find 94 95 Stop ongoing P2P device discovery or other operation (connect, listen 96 mode). 97 98 p2p_flush 99 100 Flush P2P peer table and state. 101 102 Group Formation 103 104 p2p_prov_disc <peer device address> <display|keypad|pbc> 105 106 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. 112 113 p2p_connect <peer device address> <pbc|pin|PIN#> [label|display|keypad] 114 [persistent] [join|auth] [go_intent=<0..15>] [freq=<in MHz>] 115 116 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. 119 120 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). [label|display|keypad] is used with PIN method 125 to specify which PIN is used (label=PIN from local label, 126 display=dynamically generated random PIN from local display, 127 keypad=PIN entered from peer device label or display). "persistent" 128 parameter can be used to request a persistent group to be formed. 129 130 "join" indicates that this is a command to join an existing group as a 131 client. It skips the GO Negotiation part. This will send a Provision 132 Discovery Request message to the target GO before associating for WPS 133 provisioning. 134 135 "auth" indicates that the WPS parameters are authorized for the peer 136 device without actually starting GO Negotiation (i.e., the peer is 137 expected to initiate GO Negotiation). This is mainly for testing 138 purposes. 139 140 "go_intent" can be used to override the default GO Intent for this GO 141 Negotiation. 142 143 "freq" can be used to set a forced operating channel (e.g., freq=2412 144 to select 2.4 GHz channel 1). 145 146 p2p_group_add [persistent|persistent=<network id>] [freq=<freq in MHz>] 147 148 Set up a P2P group owner manually (i.e., without group owner 149 negotiation with a specific peer). This is also known as autonomous 150 GO. Optional persistent=<network id> can be used to specify restart of 151 a persistent group. Optional freq=<freq in MHz> can be used to force 152 the GO to be started on a specific frequency. Special freq=2 or freq=5 153 options can be used to request the best 2.4 GHz or 5 GHz band channel 154 to be selected automatically. 155 156 p2p_reject <peer device address> 157 158 Reject connection attempt from a peer (specified with a device 159 address). This is a mechanism to reject a pending GO Negotiation with 160 a peer and request to automatically block any further connection or 161 discovery of the peer. 162 163 p2p_group_remove <group interface> 164 165 Terminate a P2P group. If a new virtual network interface was used for 166 the group, it will also be removed. The network interface name of the 167 group interface is used as a parameter for this command. 168 169 p2p_cancel 170 171 Cancel an ongoing P2P group formation related operation. 172 173 Service Discovery 174 175 p2p_serv_disc_req 176 177 Schedule a P2P service discovery request. The parameters for this 178 command are the device address of the peer device (or 00:00:00:00:00:00 179 for wildcard query that is sent to every discovered P2P peer that 180 supports service discovery) and P2P Service Query TLV(s) as hexdump. For 181 example, 182 183 p2p_serv_disc_req 00:00:00:00:00:00 02000001 184 185 schedules a request for listing all available services of all service 186 discovery protocols and requests this to be sent to all discovered 187 peers (note: this can result in long response frames). The pending 188 requests are sent during device discovery (see p2p_find). 189 190 Only a single pending wildcard query is supported, but there can be 191 multiple pending peer device specific queries (each will be sent in 192 sequence whenever the peer is found). 193 194 This command returns an identifier for the pending query (e.g., 195 "1f77628") that can be used to cancel the request. Directed requests 196 will be automatically removed when the specified peer has replied to 197 it. 198 199 For UPnP, an alternative command format can be used to specify a 200 single query TLV (i.e., a service discovery for a specific UPnP 201 service): 202 203 p2p_serv_disc_req 00:00:00:00:00:00 upnp <version hex> <ST: from M-SEARCH> 204 205 For example: 206 207 p2p_serv_disc_req 00:00:00:00:00:00 upnp 10 urn:schemas-upnp-org:device:InternetGatewayDevice:1 208 209 Additional examples for queries: 210 211 # list of all Bonjour services 212 p2p_serv_disc_req 00:00:00:00:00:00 02000101 213 214 # list of all UPnP services 215 p2p_serv_disc_req 00:00:00:00:00:00 02000201 216 217 # list of all WS-Discovery services 218 p2p_serv_disc_req 00:00:00:00:00:00 02000301 219 220 # list of all Bonjour and UPnP services 221 p2p_serv_disc_req 00:00:00:00:00:00 0200010102000202 222 223 # Apple File Sharing over TCP 224 p2p_serv_disc_req 00:00:00:00:00:00 130001010b5f6166706f766572746370c00c000c01 225 226 # Bonjour SSTH (supported service type hash) 227 p2p_serv_disc_req 00:00:00:00:00:00 05000101000000 228 229 # UPnP examples 230 p2p_serv_disc_req 00:00:00:00:00:00 upnp 10 ssdp:all 231 p2p_serv_disc_req 00:00:00:00:00:00 upnp 10 upnp:rootdevice 232 p2p_serv_disc_req 00:00:00:00:00:00 upnp 10 urn:schemas-upnp-org:service:ContentDirectory:2 233 p2p_serv_disc_req 00:00:00:00:00:00 upnp 10 uuid:6859dede-8574-59ab-9332-123456789012 234 p2p_serv_disc_req 00:00:00:00:00:00 upnp 10 urn:schemas-upnp-org:device:InternetGatewayDevice:1 235 236 p2p_serv_disc_cancel_req <query identifier> 237 238 Cancel a pending P2P service discovery request. This command takes a 239 single parameter: identifier for the pending query (the value returned 240 by p2p_serv_disc_req, e.g., "p2p_serv_disc_cancel_req 1f77628". 241 242 p2p_serv_disc_resp 243 244 Reply to a service discovery query. This command takes following 245 parameters: frequency in MHz, destination address, dialog token, 246 response TLV(s). The first three parameters are copied from the 247 request event. For example, "p2p_serv_disc_resp 2437 02:40:61:c2:f3:b7 248 1 0300000101". This command is used only if external program is used 249 to process the request (see p2p_serv_disc_external). 250 251 p2p_service_update 252 253 Indicate that local services have changed. This is used to increment 254 the P2P service indicator value so that peers know when previously 255 cached information may have changed. This is only needed when external 256 service discovery processing is enabled since the commands to 257 pre-configure services for internal processing will increment the 258 indicator automatically. 259 260 p2p_serv_disc_external <0|1> 261 262 Configure external processing of P2P service requests: 0 (default) = 263 no external processing of requests (i.e., internal code will process 264 each request based on pre-configured services), 1 = external 265 processing of requests (external program is responsible for replying 266 to service discovery requests with p2p_serv_disc_resp). Please note 267 that there is quite strict limit on how quickly the response needs to 268 be transmitted, so use of the internal processing is strongly 269 recommended. 270 271 p2p_service_add bonjour <query hexdump> <RDATA hexdump> 272 273 Add a local Bonjour service for internal SD query processing. 274 275 Examples: 276 277 # AFP Over TCP (PTR) 278 p2p_service_add bonjour 0b5f6166706f766572746370c00c000c01 074578616d706c65c027 279 # AFP Over TCP (TXT) (RDATA=null) 280 p2p_service_add bonjour 076578616d706c650b5f6166706f766572746370c00c001001 00 281 282 # IP Printing over TCP (PTR) (RDATA=MyPrinter._ipp._tcp.local.) 283 p2p_service_add bonjour 045f697070c00c000c01 094d795072696e746572c027 284 # IP Printing over TCP (TXT) (RDATA=txtvers=1,pdl=application/postscript) 285 p2p_service_add bonjour 096d797072696e746572045f697070c00c001001 09747874766572733d311a70646c3d6170706c69636174696f6e2f706f7374736372797074 286 287 # Supported Service Type Hash (SSTH) 288 p2p_service_add bonjour 000000 <32-byte bitfield as hexdump> 289 (note: see P2P spec Annex E.4 for information on how to construct the bitfield) 290 291 p2p_service_del bonjour <query hexdump> 292 293 Remove a local Bonjour service from internal SD query processing. 294 295 p2p_service_add upnp <version hex> <service> 296 297 Add a local UPnP service for internal SD query processing. 298 299 Examples: 300 301 p2p_service_add upnp 10 uuid:6859dede-8574-59ab-9332-123456789012::upnp:rootdevice 302 p2p_service_add upnp 10 uuid:5566d33e-9774-09ab-4822-333456785632::upnp:rootdevice 303 p2p_service_add upnp 10 uuid:1122de4e-8574-59ab-9322-333456789044::urn:schemas-upnp-org:service:ContentDirectory:2 304 p2p_service_add upnp 10 uuid:5566d33e-9774-09ab-4822-333456785632::urn:schemas-upnp-org:service:ContentDirectory:2 305 p2p_service_add upnp 10 uuid:6859dede-8574-59ab-9332-123456789012::urn:schemas-upnp-org:device:InternetGatewayDevice:1 306 307 p2p_service_del upnp <version hex> <service> 308 309 Remove a local UPnP service from internal SD query processing. 310 311 p2p_service_flush 312 313 Remove all local services from internal SD query processing. 314 315 Invitation 316 317 p2p_invite [persistent=<network id>|group=<group ifname>] [peer=address] 318 [go_dev_addr=address] 319 320 Invite a peer to join a group (e.g., group=wlan1) or to reinvoke a 321 persistent group (e.g., persistent=4). If the peer device is the GO of 322 the persisten group, the peer parameter is not needed. Otherwise it is 323 used to specify which device to invite. go_dev_addr parameter can be 324 used to override the GO device address for Invitation Request should 325 it be not known for some reason (this should not be needed in most 326 cases). 327 328 Group Operations 329 330 (These are used on the group interface.) 331 332 wps_pin <any|address> <PIN> 333 334 Start WPS PIN method. This allows a single WPS Enrollee to connect to 335 the AP/GO. This is used on the GO when a P2P client joins an existing 336 group. The second parameter is the address of the Enrollee or a string 337 "any" to allow any station to use the entered PIN (which will restrict 338 the PIN for one-time-use). PIN is the Enrollee PIN read either from a 339 label or display on the P2P Client/WPS Enrollee. 340 341 wps_pbc 342 343 Start WPS PBC method (i.e., push the button). This allows a single WPS 344 Enrollee to connect to the AP/GO. This is used on the GO when a P2P 345 client joins an existing group. 346 347 p2p_get_passphrase 348 349 Get the passphrase for a group (only available when acting as a GO). 350 351 p2p_presence_req [<duration> <interval>] [<duration> <interval>] 352 353 Send a P2P Presence Request to the GO (this is only available when 354 acting as a P2P client). If no duration/interval pairs are given, the 355 request indicates that this client has no special needs for GO 356 presence. the first parameter pair gives the preferred duration and 357 interval values in microseconds. If the second pair is included, that 358 indicates which value would be acceptable. 359 360 Parameters 361 362 p2p_ext_listen [<period> <interval>] 363 364 Configure Extended Listen Timing. If the parameters are omitted, this 365 feature is disabled. If the parameters are included, Listen State will 366 be entered every interval msec for at least period msec. Both values 367 have acceptable range of 1-65535 (with interval obviously having to be 368 larger than or equal to duration). If the P2P module is not idle at 369 the time the Extended Listen Timing timeout occurs, the Listen State 370 operation will be skipped. 371 372 The configured values will also be advertised to other P2P Devices. The 373 received values are available in the p2p_peer command output: 374 375 ext_listen_period=100 ext_listen_interval=5000 376 377 p2p_set <field> <value> 378 379 Change dynamic P2P parameters 380 381 p2p_set discoverability <0/1> 382 383 Disable/enable advertisement of client discoverability. This is 384 enabled by default and this parameter is mainly used to allow testing 385 of device discoverability. 386 387 p2p_set managed <0/1> 388 389 Disable/enable managed P2P Device operations. This is disabled by 390 default. 391 392 p2p_set listen_channel <1/6/11> 393 394 Set P2P Listen channel. This is mainly meant for testing purposes and 395 changing the Listen channel during normal operations can result in 396 protocol failures. 397 398 p2p_set ssid_postfix <postfix> 399 400 Set postfix string to be added to the automatically generated P2P SSID 401 (DIRECT-<two random characters>). For example, postfix of "-testing" 402 could result in the SSID becoming DIRECT-ab-testing. 403 404 set <field> <value> 405 406 Set global configuration parameters which may also affect P2P 407 operations. The format on these parameters is same as is used in 408 wpa_supplicant.conf. Only the parameters listen here should be 409 changed. Modifying other parameters may result in incorrect behavior 410 since not all existing users of the parameters are updated. 411 412 set uuid <UUID> 413 414 Set WPS UUID (by default, this is generated based on the MAC address). 415 416 set device_name <device name> 417 418 Set WPS Device Name (also included in some P2P messages). 419 420 set manufacturer <manufacturer> 421 422 Set WPS Manufacturer. 423 424 set model_name <model name> 425 426 Set WPS Model Name. 427 428 set model_number <model number> 429 430 Set WPS Model Number. 431 432 set serial_number <serial number> 433 434 Set WPS Serial Number. 435 436 set device_type <device type> 437 438 Set WPS Device Type. 439 440 set os_version <OS version> 441 442 Set WPS OS Version. 443 444 set config_methods <config methods> 445 446 Set WPS Configuration Methods. 447 448 set sec_device_type <device type> 449 450 Add a new Secondary Device Type. 451 452 set p2p_go_intent <GO intent> 453 454 Set the default P2P GO Intent. Note: This value can be overridden in 455 p2p_connect command and as such, there should be no need to change the 456 default value here during normal operations. 457 458 set p2p_ssid_postfix <P2P SSID postfix> 459 460 Set P2P SSID postfix. 461 462 set persistent_reconnect <0/1> 463 464 Disable/enabled persistent reconnect for reinvocation of persistent 465 groups. If enabled, invitations to reinvoke a persistent group will be 466 accepted without separate authorization (e.g., user interaction). 467 468 set country <two character country code> 469 470 Set country code (this is included in some P2P messages). 471 472 Status 473 474 p2p_peers [discovered] 475 476 List P2P Device Addresses of all the P2P peers we know. The optional 477 "discovered" parameter filters out the peers that we have not fully 478 discovered, i.e., which we have only seen in a received Probe Request 479 frame. 480 481 p2p_peer <P2P Device Address> 482 483 Fetch information about a known P2P peer. 484 485 Group Status 486 487 (These are used on the group interface.) 488 489 status 490 491 Show status information (connection state, role, use encryption 492 parameters, IP address, etc.). 493 494 sta 495 496 Show information about an associated station (when acting in AP/GO role). 497 498 all_sta 499 500 Lists the currently associated stations. 501 502 Configuration data 503 504 list_networks 505 506 Lists the configured networks, including stored information for 507 persistent groups. The identifier in this list is used with 508 p2p_group_add and p2p_invite to indicate which persistent group is to 509 be reinvoked. 510 511 remove_network <network id> 512 513 Remove a network entry from configuration. 514 515 516 wpa_cli action script 517 --------------------- 518 519 See examples/p2p-action.sh 520 521 TODO: describe DHCP/DNS setup 522 TODO: cross-connection 523
