1 /*
2 * Wi-Fi Direct - P2P provision discovery
3 * Copyright (c) 2009-2010, Atheros Communications
4 *
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
7 */
8
9 #include "includes.h"
10
11 #include "common.h"
12 #include "common/ieee802_11_defs.h"
13 #include "common/wpa_ctrl.h"
14 #include "wps/wps_defs.h"
15 #include "p2p_i.h"
16 #include "p2p.h"
17
18
19 /*
20 * Number of retries to attempt for provision discovery requests
21 * in case the peer is not listening.
22 */
23 #define MAX_PROV_DISC_REQ_RETRIES 120
24
25
p2p_build_wps_ie_config_methods(struct wpabuf * buf,u16 config_methods)26 static void p2p_build_wps_ie_config_methods(struct wpabuf *buf,
27 u16 config_methods)
28 {
29 u8 *len;
30 wpabuf_put_u8(buf, WLAN_EID_VENDOR_SPECIFIC);
31 len = wpabuf_put(buf, 1);
32 wpabuf_put_be32(buf, WPS_DEV_OUI_WFA);
33
34 /* Config Methods */
35 wpabuf_put_be16(buf, ATTR_CONFIG_METHODS);
36 wpabuf_put_be16(buf, 2);
37 wpabuf_put_be16(buf, config_methods);
38
39 p2p_buf_update_ie_hdr(buf, len);
40 }
41
42
p2p_build_prov_disc_req(struct p2p_data * p2p,u8 dialog_token,u16 config_methods,struct p2p_device * go)43 static struct wpabuf * p2p_build_prov_disc_req(struct p2p_data *p2p,
44 u8 dialog_token,
45 u16 config_methods,
46 struct p2p_device *go)
47 {
48 struct wpabuf *buf;
49 u8 *len;
50 size_t extra = 0;
51
52 #ifdef CONFIG_WIFI_DISPLAY
53 if (p2p->wfd_ie_prov_disc_req)
54 extra = wpabuf_len(p2p->wfd_ie_prov_disc_req);
55 #endif /* CONFIG_WIFI_DISPLAY */
56
57 if (p2p->vendor_elem && p2p->vendor_elem[VENDOR_ELEM_P2P_PD_REQ])
58 extra += wpabuf_len(p2p->vendor_elem[VENDOR_ELEM_P2P_PD_REQ]);
59
60 buf = wpabuf_alloc(1000 + extra);
61 if (buf == NULL)
62 return NULL;
63
64 p2p_buf_add_public_action_hdr(buf, P2P_PROV_DISC_REQ, dialog_token);
65
66 len = p2p_buf_add_ie_hdr(buf);
67 p2p_buf_add_capability(buf, p2p->dev_capab &
68 ~P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY, 0);
69 p2p_buf_add_device_info(buf, p2p, NULL);
70 if (go) {
71 p2p_buf_add_group_id(buf, go->info.p2p_device_addr,
72 go->oper_ssid, go->oper_ssid_len);
73 }
74 p2p_buf_update_ie_hdr(buf, len);
75
76 /* WPS IE with Config Methods attribute */
77 p2p_build_wps_ie_config_methods(buf, config_methods);
78
79 #ifdef CONFIG_WIFI_DISPLAY
80 if (p2p->wfd_ie_prov_disc_req)
81 wpabuf_put_buf(buf, p2p->wfd_ie_prov_disc_req);
82 #endif /* CONFIG_WIFI_DISPLAY */
83
84 if (p2p->vendor_elem && p2p->vendor_elem[VENDOR_ELEM_P2P_PD_REQ])
85 wpabuf_put_buf(buf, p2p->vendor_elem[VENDOR_ELEM_P2P_PD_REQ]);
86
87 return buf;
88 }
89
90
p2p_build_prov_disc_resp(struct p2p_data * p2p,u8 dialog_token,u16 config_methods,const u8 * group_id,size_t group_id_len)91 static struct wpabuf * p2p_build_prov_disc_resp(struct p2p_data *p2p,
92 u8 dialog_token,
93 u16 config_methods,
94 const u8 *group_id,
95 size_t group_id_len)
96 {
97 struct wpabuf *buf;
98 size_t extra = 0;
99
100 #ifdef CONFIG_WIFI_DISPLAY
101 struct wpabuf *wfd_ie = p2p->wfd_ie_prov_disc_resp;
102 if (wfd_ie && group_id) {
103 size_t i;
104 for (i = 0; i < p2p->num_groups; i++) {
105 struct p2p_group *g = p2p->groups[i];
106 struct wpabuf *ie;
107 if (!p2p_group_is_group_id_match(g, group_id,
108 group_id_len))
109 continue;
110 ie = p2p_group_get_wfd_ie(g);
111 if (ie) {
112 wfd_ie = ie;
113 break;
114 }
115 }
116 }
117 if (wfd_ie)
118 extra = wpabuf_len(wfd_ie);
119 #endif /* CONFIG_WIFI_DISPLAY */
120
121 if (p2p->vendor_elem && p2p->vendor_elem[VENDOR_ELEM_P2P_PD_RESP])
122 extra += wpabuf_len(p2p->vendor_elem[VENDOR_ELEM_P2P_PD_RESP]);
123
124 buf = wpabuf_alloc(100 + extra);
125 if (buf == NULL)
126 return NULL;
127
128 p2p_buf_add_public_action_hdr(buf, P2P_PROV_DISC_RESP, dialog_token);
129
130 /* WPS IE with Config Methods attribute */
131 p2p_build_wps_ie_config_methods(buf, config_methods);
132
133 #ifdef CONFIG_WIFI_DISPLAY
134 if (wfd_ie)
135 wpabuf_put_buf(buf, wfd_ie);
136 #endif /* CONFIG_WIFI_DISPLAY */
137
138 if (p2p->vendor_elem && p2p->vendor_elem[VENDOR_ELEM_P2P_PD_RESP])
139 wpabuf_put_buf(buf, p2p->vendor_elem[VENDOR_ELEM_P2P_PD_RESP]);
140
141 return buf;
142 }
143
144
p2p_process_prov_disc_req(struct p2p_data * p2p,const u8 * sa,const u8 * data,size_t len,int rx_freq)145 void p2p_process_prov_disc_req(struct p2p_data *p2p, const u8 *sa,
146 const u8 *data, size_t len, int rx_freq)
147 {
148 struct p2p_message msg;
149 struct p2p_device *dev;
150 int freq;
151 int reject = 1;
152 struct wpabuf *resp;
153
154 if (p2p_parse(data, len, &msg))
155 return;
156
157 p2p_dbg(p2p, "Received Provision Discovery Request from " MACSTR
158 " with config methods 0x%x (freq=%d)",
159 MAC2STR(sa), msg.wps_config_methods, rx_freq);
160
161 dev = p2p_get_device(p2p, sa);
162 if (dev == NULL || (dev->flags & P2P_DEV_PROBE_REQ_ONLY)) {
163 p2p_dbg(p2p, "Provision Discovery Request from unknown peer "
164 MACSTR, MAC2STR(sa));
165
166 if (p2p_add_device(p2p, sa, rx_freq, NULL, 0, data + 1, len - 1,
167 0)) {
168 p2p_dbg(p2p, "Provision Discovery Request add device failed "
169 MACSTR, MAC2STR(sa));
170 }
171 } else if (msg.wfd_subelems) {
172 wpabuf_free(dev->info.wfd_subelems);
173 dev->info.wfd_subelems = wpabuf_dup(msg.wfd_subelems);
174 }
175
176 if (!(msg.wps_config_methods &
177 (WPS_CONFIG_DISPLAY | WPS_CONFIG_KEYPAD |
178 WPS_CONFIG_PUSHBUTTON))) {
179 p2p_dbg(p2p, "Unsupported Config Methods in Provision Discovery Request");
180 goto out;
181 }
182
183 if (msg.group_id) {
184 size_t i;
185 for (i = 0; i < p2p->num_groups; i++) {
186 if (p2p_group_is_group_id_match(p2p->groups[i],
187 msg.group_id,
188 msg.group_id_len))
189 break;
190 }
191 if (i == p2p->num_groups) {
192 p2p_dbg(p2p, "PD request for unknown P2P Group ID - reject");
193 goto out;
194 }
195 }
196
197 if (dev)
198 dev->flags &= ~(P2P_DEV_PD_PEER_DISPLAY |
199 P2P_DEV_PD_PEER_KEYPAD);
200 if (msg.wps_config_methods & WPS_CONFIG_DISPLAY) {
201 p2p_dbg(p2p, "Peer " MACSTR
202 " requested us to show a PIN on display", MAC2STR(sa));
203 if (dev)
204 dev->flags |= P2P_DEV_PD_PEER_KEYPAD;
205 } else if (msg.wps_config_methods & WPS_CONFIG_KEYPAD) {
206 p2p_dbg(p2p, "Peer " MACSTR
207 " requested us to write its PIN using keypad",
208 MAC2STR(sa));
209 if (dev)
210 dev->flags |= P2P_DEV_PD_PEER_DISPLAY;
211 }
212
213 reject = 0;
214
215 out:
216 resp = p2p_build_prov_disc_resp(p2p, msg.dialog_token,
217 reject ? 0 : msg.wps_config_methods,
218 msg.group_id, msg.group_id_len);
219 if (resp == NULL) {
220 p2p_parse_free(&msg);
221 return;
222 }
223 p2p_dbg(p2p, "Sending Provision Discovery Response");
224 if (rx_freq > 0)
225 freq = rx_freq;
226 else
227 freq = p2p_channel_to_freq(p2p->cfg->reg_class,
228 p2p->cfg->channel);
229 if (freq < 0) {
230 p2p_dbg(p2p, "Unknown regulatory class/channel");
231 wpabuf_free(resp);
232 p2p_parse_free(&msg);
233 return;
234 }
235 p2p->pending_action_state = P2P_NO_PENDING_ACTION;
236 if (p2p_send_action(p2p, freq, sa, p2p->cfg->dev_addr,
237 p2p->cfg->dev_addr,
238 wpabuf_head(resp), wpabuf_len(resp), 200) < 0) {
239 p2p_dbg(p2p, "Failed to send Action frame");
240 } else
241 p2p->send_action_in_progress = 1;
242
243 wpabuf_free(resp);
244
245 if (!reject && p2p->cfg->prov_disc_req) {
246 const u8 *dev_addr = sa;
247 if (msg.p2p_device_addr)
248 dev_addr = msg.p2p_device_addr;
249 p2p->cfg->prov_disc_req(p2p->cfg->cb_ctx, sa,
250 msg.wps_config_methods,
251 dev_addr, msg.pri_dev_type,
252 msg.device_name, msg.config_methods,
253 msg.capability ? msg.capability[0] : 0,
254 msg.capability ? msg.capability[1] :
255 0,
256 msg.group_id, msg.group_id_len);
257 }
258 p2p_parse_free(&msg);
259 }
260
261
p2p_process_prov_disc_resp(struct p2p_data * p2p,const u8 * sa,const u8 * data,size_t len)262 void p2p_process_prov_disc_resp(struct p2p_data *p2p, const u8 *sa,
263 const u8 *data, size_t len)
264 {
265 struct p2p_message msg;
266 struct p2p_device *dev;
267 u16 report_config_methods = 0, req_config_methods;
268 int success = 0;
269
270 if (p2p_parse(data, len, &msg))
271 return;
272
273 p2p_dbg(p2p, "Received Provision Discovery Response from " MACSTR
274 " with config methods 0x%x",
275 MAC2STR(sa), msg.wps_config_methods);
276
277 dev = p2p_get_device(p2p, sa);
278 if (dev == NULL || !dev->req_config_methods) {
279 p2p_dbg(p2p, "Ignore Provision Discovery Response from " MACSTR
280 " with no pending request", MAC2STR(sa));
281 p2p_parse_free(&msg);
282 return;
283 }
284
285 if (dev->dialog_token != msg.dialog_token) {
286 p2p_dbg(p2p, "Ignore Provision Discovery Response with unexpected Dialog Token %u (expected %u)",
287 msg.dialog_token, dev->dialog_token);
288 p2p_parse_free(&msg);
289 return;
290 }
291
292 if (p2p->pending_action_state == P2P_PENDING_PD) {
293 os_memset(p2p->pending_pd_devaddr, 0, ETH_ALEN);
294 p2p->pending_action_state = P2P_NO_PENDING_ACTION;
295 }
296
297 /*
298 * Use a local copy of the requested config methods since
299 * p2p_reset_pending_pd() can clear this in the peer entry.
300 */
301 req_config_methods = dev->req_config_methods;
302
303 /*
304 * If the response is from the peer to whom a user initiated request
305 * was sent earlier, we reset that state info here.
306 */
307 if (p2p->user_initiated_pd &&
308 os_memcmp(p2p->pending_pd_devaddr, sa, ETH_ALEN) == 0)
309 p2p_reset_pending_pd(p2p);
310
311 if (msg.wps_config_methods != req_config_methods) {
312 p2p_dbg(p2p, "Peer rejected our Provision Discovery Request (received config_methods 0x%x expected 0x%x",
313 msg.wps_config_methods, req_config_methods);
314 if (p2p->cfg->prov_disc_fail)
315 p2p->cfg->prov_disc_fail(p2p->cfg->cb_ctx, sa,
316 P2P_PROV_DISC_REJECTED);
317 p2p_parse_free(&msg);
318 goto out;
319 }
320
321 report_config_methods = req_config_methods;
322 dev->flags &= ~(P2P_DEV_PD_PEER_DISPLAY |
323 P2P_DEV_PD_PEER_KEYPAD);
324 if (req_config_methods & WPS_CONFIG_DISPLAY) {
325 p2p_dbg(p2p, "Peer " MACSTR
326 " accepted to show a PIN on display", MAC2STR(sa));
327 dev->flags |= P2P_DEV_PD_PEER_DISPLAY;
328 } else if (msg.wps_config_methods & WPS_CONFIG_KEYPAD) {
329 p2p_dbg(p2p, "Peer " MACSTR
330 " accepted to write our PIN using keypad",
331 MAC2STR(sa));
332 dev->flags |= P2P_DEV_PD_PEER_KEYPAD;
333 }
334
335 /* Store the provisioning info */
336 dev->wps_prov_info = msg.wps_config_methods;
337
338 p2p_parse_free(&msg);
339 success = 1;
340
341 out:
342 dev->req_config_methods = 0;
343 p2p->cfg->send_action_done(p2p->cfg->cb_ctx);
344 if (dev->flags & P2P_DEV_PD_BEFORE_GO_NEG) {
345 p2p_dbg(p2p, "Start GO Neg after the PD-before-GO-Neg workaround with "
346 MACSTR, MAC2STR(dev->info.p2p_device_addr));
347 dev->flags &= ~P2P_DEV_PD_BEFORE_GO_NEG;
348 p2p_connect_send(p2p, dev);
349 return;
350 }
351 if (success && p2p->cfg->prov_disc_resp)
352 p2p->cfg->prov_disc_resp(p2p->cfg->cb_ctx, sa,
353 report_config_methods);
354
355 if (p2p->state == P2P_PD_DURING_FIND) {
356 p2p_clear_timeout(p2p);
357 p2p_continue_find(p2p);
358 }
359 }
360
361
p2p_send_prov_disc_req(struct p2p_data * p2p,struct p2p_device * dev,int join,int force_freq)362 int p2p_send_prov_disc_req(struct p2p_data *p2p, struct p2p_device *dev,
363 int join, int force_freq)
364 {
365 struct wpabuf *req;
366 int freq;
367
368 if (force_freq > 0)
369 freq = force_freq;
370 else
371 freq = dev->listen_freq > 0 ? dev->listen_freq :
372 dev->oper_freq;
373 if (freq <= 0) {
374 p2p_dbg(p2p, "No Listen/Operating frequency known for the peer "
375 MACSTR " to send Provision Discovery Request",
376 MAC2STR(dev->info.p2p_device_addr));
377 return -1;
378 }
379
380 if (dev->flags & P2P_DEV_GROUP_CLIENT_ONLY) {
381 if (!(dev->info.dev_capab &
382 P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY)) {
383 p2p_dbg(p2p, "Cannot use PD with P2P Device " MACSTR
384 " that is in a group and is not discoverable",
385 MAC2STR(dev->info.p2p_device_addr));
386 return -1;
387 }
388 /* TODO: use device discoverability request through GO */
389 }
390
391 req = p2p_build_prov_disc_req(p2p, dev->dialog_token,
392 dev->req_config_methods,
393 join ? dev : NULL);
394 if (req == NULL)
395 return -1;
396
397 if (p2p->state != P2P_IDLE)
398 p2p_stop_listen_for_freq(p2p, freq);
399 p2p->pending_action_state = P2P_PENDING_PD;
400 if (p2p_send_action(p2p, freq, dev->info.p2p_device_addr,
401 p2p->cfg->dev_addr, dev->info.p2p_device_addr,
402 wpabuf_head(req), wpabuf_len(req), 200) < 0) {
403 p2p_dbg(p2p, "Failed to send Action frame");
404 wpabuf_free(req);
405 return -1;
406 }
407
408 os_memcpy(p2p->pending_pd_devaddr, dev->info.p2p_device_addr, ETH_ALEN);
409
410 wpabuf_free(req);
411 return 0;
412 }
413
414
p2p_prov_disc_req(struct p2p_data * p2p,const u8 * peer_addr,u16 config_methods,int join,int force_freq,int user_initiated_pd)415 int p2p_prov_disc_req(struct p2p_data *p2p, const u8 *peer_addr,
416 u16 config_methods, int join, int force_freq,
417 int user_initiated_pd)
418 {
419 struct p2p_device *dev;
420
421 dev = p2p_get_device(p2p, peer_addr);
422 if (dev == NULL)
423 dev = p2p_get_device_interface(p2p, peer_addr);
424 if (dev == NULL || (dev->flags & P2P_DEV_PROBE_REQ_ONLY)) {
425 p2p_dbg(p2p, "Provision Discovery Request destination " MACSTR
426 " not yet known", MAC2STR(peer_addr));
427 return -1;
428 }
429
430 p2p_dbg(p2p, "Provision Discovery Request with " MACSTR
431 " (config methods 0x%x)",
432 MAC2STR(peer_addr), config_methods);
433 if (config_methods == 0)
434 return -1;
435
436 /* Reset provisioning info */
437 dev->wps_prov_info = 0;
438
439 dev->req_config_methods = config_methods;
440 if (join)
441 dev->flags |= P2P_DEV_PD_FOR_JOIN;
442 else
443 dev->flags &= ~P2P_DEV_PD_FOR_JOIN;
444
445 if (p2p->state != P2P_IDLE && p2p->state != P2P_SEARCH &&
446 p2p->state != P2P_LISTEN_ONLY) {
447 p2p_dbg(p2p, "Busy with other operations; postpone Provision Discovery Request with "
448 MACSTR " (config methods 0x%x)",
449 MAC2STR(peer_addr), config_methods);
450 return 0;
451 }
452
453 p2p->user_initiated_pd = user_initiated_pd;
454 p2p->pd_force_freq = force_freq;
455
456 if (p2p->user_initiated_pd)
457 p2p->pd_retries = MAX_PROV_DISC_REQ_RETRIES;
458
459 /*
460 * Assign dialog token here to use the same value in each retry within
461 * the same PD exchange.
462 */
463 dev->dialog_token++;
464 if (dev->dialog_token == 0)
465 dev->dialog_token = 1;
466
467 return p2p_send_prov_disc_req(p2p, dev, join, force_freq);
468 }
469
470
p2p_reset_pending_pd(struct p2p_data * p2p)471 void p2p_reset_pending_pd(struct p2p_data *p2p)
472 {
473 struct p2p_device *dev;
474
475 dl_list_for_each(dev, &p2p->devices, struct p2p_device, list) {
476 if (os_memcmp(p2p->pending_pd_devaddr,
477 dev->info.p2p_device_addr, ETH_ALEN))
478 continue;
479 if (!dev->req_config_methods)
480 continue;
481 if (dev->flags & P2P_DEV_PD_FOR_JOIN)
482 continue;
483 /* Reset the config methods of the device */
484 dev->req_config_methods = 0;
485 }
486
487 p2p->user_initiated_pd = 0;
488 os_memset(p2p->pending_pd_devaddr, 0, ETH_ALEN);
489 p2p->pd_retries = 0;
490 p2p->pd_force_freq = 0;
491 }
492