p2p_pd.c revision 91c40cdce17424d9a4718876becf0b7811cf68f2
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 "wps/wps_defs.h"
14#include "p2p_i.h"
15#include "p2p.h"
16
17
18/*
19 * Number of retries to attempt for provision discovery requests
20 * in case the peer is not listening.
21 */
22#define MAX_PROV_DISC_REQ_RETRIES 10
23
24
25static void p2p_build_wps_ie_config_methods(struct wpabuf *buf,
26					    u16 config_methods)
27{
28	u8 *len;
29	wpabuf_put_u8(buf, WLAN_EID_VENDOR_SPECIFIC);
30	len = wpabuf_put(buf, 1);
31	wpabuf_put_be32(buf, WPS_DEV_OUI_WFA);
32
33	/* Config Methods */
34	wpabuf_put_be16(buf, ATTR_CONFIG_METHODS);
35	wpabuf_put_be16(buf, 2);
36	wpabuf_put_be16(buf, config_methods);
37
38	p2p_buf_update_ie_hdr(buf, len);
39}
40
41
42static struct wpabuf * p2p_build_prov_disc_req(struct p2p_data *p2p,
43					       u8 dialog_token,
44					       u16 config_methods,
45					       struct p2p_device *go)
46{
47	struct wpabuf *buf;
48	u8 *len;
49	size_t extra = 0;
50
51#ifdef CONFIG_WIFI_DISPLAY
52	if (p2p->wfd_ie_prov_disc_req)
53		extra = wpabuf_len(p2p->wfd_ie_prov_disc_req);
54#endif /* CONFIG_WIFI_DISPLAY */
55
56	buf = wpabuf_alloc(1000 + extra);
57	if (buf == NULL)
58		return NULL;
59
60	p2p_buf_add_public_action_hdr(buf, P2P_PROV_DISC_REQ, dialog_token);
61
62	len = p2p_buf_add_ie_hdr(buf);
63	p2p_buf_add_capability(buf, p2p->dev_capab &
64			       ~P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY, 0);
65	p2p_buf_add_device_info(buf, p2p, NULL);
66	if (go) {
67		p2p_buf_add_group_id(buf, go->info.p2p_device_addr,
68				     go->oper_ssid, go->oper_ssid_len);
69	}
70	p2p_buf_update_ie_hdr(buf, len);
71
72	/* WPS IE with Config Methods attribute */
73	p2p_build_wps_ie_config_methods(buf, config_methods);
74
75#ifdef CONFIG_WIFI_DISPLAY
76	if (p2p->wfd_ie_prov_disc_req)
77		wpabuf_put_buf(buf, p2p->wfd_ie_prov_disc_req);
78#endif /* CONFIG_WIFI_DISPLAY */
79
80	return buf;
81}
82
83
84static struct wpabuf * p2p_build_prov_disc_resp(struct p2p_data *p2p,
85						u8 dialog_token,
86						u16 config_methods,
87						const u8 *group_id,
88						size_t group_id_len)
89{
90	struct wpabuf *buf;
91	size_t extra = 0;
92
93#ifdef CONFIG_WIFI_DISPLAY
94	struct wpabuf *wfd_ie = p2p->wfd_ie_prov_disc_resp;
95	if (wfd_ie && group_id) {
96		size_t i;
97		for (i = 0; i < p2p->num_groups; i++) {
98			struct p2p_group *g = p2p->groups[i];
99			struct wpabuf *ie;
100			if (!p2p_group_is_group_id_match(g, group_id,
101							 group_id_len))
102				continue;
103			ie = p2p_group_get_wfd_ie(g);
104			if (ie) {
105				wfd_ie = ie;
106				break;
107			}
108		}
109	}
110	if (wfd_ie)
111		extra = wpabuf_len(wfd_ie);
112#endif /* CONFIG_WIFI_DISPLAY */
113
114	buf = wpabuf_alloc(100 + extra);
115	if (buf == NULL)
116		return NULL;
117
118	p2p_buf_add_public_action_hdr(buf, P2P_PROV_DISC_RESP, dialog_token);
119
120	/* WPS IE with Config Methods attribute */
121	p2p_build_wps_ie_config_methods(buf, config_methods);
122
123#ifdef CONFIG_WIFI_DISPLAY
124	if (wfd_ie)
125		wpabuf_put_buf(buf, wfd_ie);
126#endif /* CONFIG_WIFI_DISPLAY */
127
128	return buf;
129}
130
131
132void p2p_process_prov_disc_req(struct p2p_data *p2p, const u8 *sa,
133			       const u8 *data, size_t len, int rx_freq)
134{
135	struct p2p_message msg;
136	struct p2p_device *dev;
137	int freq;
138	int reject = 1;
139	struct wpabuf *resp;
140
141	if (p2p_parse(data, len, &msg))
142		return;
143
144	wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
145		"P2P: Received Provision Discovery Request from " MACSTR
146		" with config methods 0x%x (freq=%d)",
147		MAC2STR(sa), msg.wps_config_methods, rx_freq);
148
149	dev = p2p_get_device(p2p, sa);
150	if (dev == NULL || (dev->flags & P2P_DEV_PROBE_REQ_ONLY)) {
151		wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
152			"P2P: Provision Discovery Request from "
153			"unknown peer " MACSTR, MAC2STR(sa));
154		if (p2p_add_device(p2p, sa, rx_freq, 0, data + 1, len - 1, 0))
155		{
156			wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
157			        "P2P: Provision Discovery Request add device "
158				"failed " MACSTR, MAC2STR(sa));
159		}
160	} else if (msg.wfd_subelems) {
161		wpabuf_free(dev->info.wfd_subelems);
162		dev->info.wfd_subelems = wpabuf_dup(msg.wfd_subelems);
163	}
164
165	if (!(msg.wps_config_methods &
166	      (WPS_CONFIG_DISPLAY | WPS_CONFIG_KEYPAD |
167	       WPS_CONFIG_PUSHBUTTON))) {
168		wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Unsupported "
169			"Config Methods in Provision Discovery Request");
170		goto out;
171	}
172
173	if (msg.group_id) {
174		size_t i;
175		for (i = 0; i < p2p->num_groups; i++) {
176			if (p2p_group_is_group_id_match(p2p->groups[i],
177							msg.group_id,
178							msg.group_id_len))
179				break;
180		}
181		if (i == p2p->num_groups) {
182			wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: PD "
183				"request for unknown P2P Group ID - reject");
184			goto out;
185		}
186	}
187
188	if (dev)
189		dev->flags &= ~(P2P_DEV_PD_PEER_DISPLAY |
190				P2P_DEV_PD_PEER_KEYPAD);
191	if (msg.wps_config_methods & WPS_CONFIG_DISPLAY) {
192		wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Peer " MACSTR
193			" requested us to show a PIN on display", MAC2STR(sa));
194		if (dev)
195			dev->flags |= P2P_DEV_PD_PEER_KEYPAD;
196	} else if (msg.wps_config_methods & WPS_CONFIG_KEYPAD) {
197		wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Peer " MACSTR
198			" requested us to write its PIN using keypad",
199			MAC2STR(sa));
200		if (dev)
201			dev->flags |= P2P_DEV_PD_PEER_DISPLAY;
202	}
203
204	reject = 0;
205
206out:
207	resp = p2p_build_prov_disc_resp(p2p, msg.dialog_token,
208					reject ? 0 : msg.wps_config_methods,
209					msg.group_id, msg.group_id_len);
210	if (resp == NULL) {
211		p2p_parse_free(&msg);
212		return;
213	}
214	wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
215		"P2P: Sending Provision Discovery Response");
216	if (rx_freq > 0)
217		freq = rx_freq;
218	else
219		freq = p2p_channel_to_freq(p2p->cfg->country,
220					   p2p->cfg->reg_class,
221					   p2p->cfg->channel);
222	if (freq < 0) {
223		wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
224			"P2P: Unknown regulatory class/channel");
225		wpabuf_free(resp);
226		p2p_parse_free(&msg);
227		return;
228	}
229	p2p->pending_action_state = P2P_NO_PENDING_ACTION;
230	if (p2p_send_action(p2p, freq, sa, p2p->cfg->dev_addr,
231			    p2p->cfg->dev_addr,
232			    wpabuf_head(resp), wpabuf_len(resp), 200) < 0) {
233		wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
234			"P2P: Failed to send Action frame");
235	}
236
237	wpabuf_free(resp);
238
239	if (!reject && p2p->cfg->prov_disc_req) {
240		const u8 *dev_addr = sa;
241		if (msg.p2p_device_addr)
242			dev_addr = msg.p2p_device_addr;
243		p2p->cfg->prov_disc_req(p2p->cfg->cb_ctx, sa,
244					msg.wps_config_methods,
245					dev_addr, msg.pri_dev_type,
246					msg.device_name, msg.config_methods,
247					msg.capability ? msg.capability[0] : 0,
248					msg.capability ? msg.capability[1] :
249					0,
250					msg.group_id, msg.group_id_len);
251	}
252	p2p_parse_free(&msg);
253}
254
255
256void p2p_process_prov_disc_resp(struct p2p_data *p2p, const u8 *sa,
257				const u8 *data, size_t len)
258{
259	struct p2p_message msg;
260	struct p2p_device *dev;
261	u16 report_config_methods = 0;
262	int success = 0;
263
264	if (p2p_parse(data, len, &msg))
265		return;
266
267	wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
268		"P2P: Received Provision Discovery Response from " MACSTR
269		" with config methods 0x%x",
270		MAC2STR(sa), msg.wps_config_methods);
271
272	dev = p2p_get_device(p2p, sa);
273	if (dev == NULL || !dev->req_config_methods) {
274		wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
275			"P2P: Ignore Provision Discovery Response from "
276			MACSTR " with no pending request", MAC2STR(sa));
277		p2p_parse_free(&msg);
278		return;
279	}
280
281	if (dev->dialog_token != msg.dialog_token) {
282		wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
283			"P2P: Ignore Provision Discovery Response with "
284			"unexpected Dialog Token %u (expected %u)",
285			msg.dialog_token, dev->dialog_token);
286		p2p_parse_free(&msg);
287		return;
288	}
289
290	if (p2p->pending_action_state == P2P_PENDING_PD) {
291		os_memset(p2p->pending_pd_devaddr, 0, ETH_ALEN);
292		p2p->pending_action_state = P2P_NO_PENDING_ACTION;
293	}
294
295	/*
296	 * If the response is from the peer to whom a user initiated request
297	 * was sent earlier, we reset that state info here.
298	 */
299	if (p2p->user_initiated_pd &&
300	    os_memcmp(p2p->pending_pd_devaddr, sa, ETH_ALEN) == 0)
301		p2p_reset_pending_pd(p2p);
302
303	if (msg.wps_config_methods != dev->req_config_methods) {
304		wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Peer rejected "
305			"our Provision Discovery Request");
306		if (p2p->cfg->prov_disc_fail)
307			p2p->cfg->prov_disc_fail(p2p->cfg->cb_ctx, sa,
308						 P2P_PROV_DISC_REJECTED);
309		p2p_parse_free(&msg);
310		goto out;
311	}
312
313	report_config_methods = dev->req_config_methods;
314	dev->flags &= ~(P2P_DEV_PD_PEER_DISPLAY |
315			P2P_DEV_PD_PEER_KEYPAD);
316	if (dev->req_config_methods & WPS_CONFIG_DISPLAY) {
317		wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Peer " MACSTR
318			" accepted to show a PIN on display", MAC2STR(sa));
319		dev->flags |= P2P_DEV_PD_PEER_DISPLAY;
320	} else if (msg.wps_config_methods & WPS_CONFIG_KEYPAD) {
321		wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Peer " MACSTR
322			" accepted to write our PIN using keypad",
323			MAC2STR(sa));
324		dev->flags |= P2P_DEV_PD_PEER_KEYPAD;
325	}
326
327	/* Store the provisioning info */
328	dev->wps_prov_info = msg.wps_config_methods;
329
330	p2p_parse_free(&msg);
331	success = 1;
332
333out:
334	dev->req_config_methods = 0;
335	p2p->cfg->send_action_done(p2p->cfg->cb_ctx);
336	if (dev->flags & P2P_DEV_PD_BEFORE_GO_NEG) {
337		wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
338			"P2P: Start GO Neg after the PD-before-GO-Neg "
339			"workaround with " MACSTR,
340			MAC2STR(dev->info.p2p_device_addr));
341		dev->flags &= ~P2P_DEV_PD_BEFORE_GO_NEG;
342		p2p_connect_send(p2p, dev);
343		return;
344	}
345	if (success && p2p->cfg->prov_disc_resp)
346		p2p->cfg->prov_disc_resp(p2p->cfg->cb_ctx, sa,
347					 report_config_methods);
348}
349
350
351int p2p_send_prov_disc_req(struct p2p_data *p2p, struct p2p_device *dev,
352			   int join, int force_freq)
353{
354	struct wpabuf *req;
355	int freq;
356
357	if (force_freq > 0)
358		freq = force_freq;
359	else
360		freq = dev->listen_freq > 0 ? dev->listen_freq :
361			dev->oper_freq;
362	if (freq <= 0) {
363		wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
364			"P2P: No Listen/Operating frequency known for the "
365			"peer " MACSTR " to send Provision Discovery Request",
366			MAC2STR(dev->info.p2p_device_addr));
367		return -1;
368	}
369
370	if (dev->flags & P2P_DEV_GROUP_CLIENT_ONLY) {
371		if (!(dev->info.dev_capab &
372		      P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY)) {
373			wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
374				"P2P: Cannot use PD with P2P Device " MACSTR
375				" that is in a group and is not discoverable",
376				MAC2STR(dev->info.p2p_device_addr));
377			return -1;
378		}
379		/* TODO: use device discoverability request through GO */
380	}
381
382	dev->dialog_token++;
383	if (dev->dialog_token == 0)
384		dev->dialog_token = 1;
385	req = p2p_build_prov_disc_req(p2p, dev->dialog_token,
386				      dev->req_config_methods,
387				      join ? dev : NULL);
388	if (req == NULL)
389		return -1;
390
391	if (p2p->state != P2P_IDLE)
392		p2p_stop_listen_for_freq(p2p, freq);
393	p2p->pending_action_state = P2P_PENDING_PD;
394	if (p2p_send_action(p2p, freq, dev->info.p2p_device_addr,
395			    p2p->cfg->dev_addr, dev->info.p2p_device_addr,
396			    wpabuf_head(req), wpabuf_len(req), 200) < 0) {
397		wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
398			"P2P: Failed to send Action frame");
399		wpabuf_free(req);
400		return -1;
401	}
402
403	os_memcpy(p2p->pending_pd_devaddr, dev->info.p2p_device_addr, ETH_ALEN);
404
405	wpabuf_free(req);
406	return 0;
407}
408
409
410int p2p_prov_disc_req(struct p2p_data *p2p, const u8 *peer_addr,
411		      u16 config_methods, int join, int force_freq)
412{
413	struct p2p_device *dev;
414
415	dev = p2p_get_device(p2p, peer_addr);
416	if (dev == NULL)
417		dev = p2p_get_device_interface(p2p, peer_addr);
418	if (dev == NULL || (dev->flags & P2P_DEV_PROBE_REQ_ONLY)) {
419		wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Provision "
420			"Discovery Request destination " MACSTR
421			" not yet known", MAC2STR(peer_addr));
422		return -1;
423	}
424
425	wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Provision Discovery "
426		"Request with " MACSTR " (config methods 0x%x)",
427		MAC2STR(peer_addr), config_methods);
428	if (config_methods == 0)
429		return -1;
430
431	/* Reset provisioning info */
432	dev->wps_prov_info = 0;
433
434	dev->req_config_methods = config_methods;
435	if (join)
436		dev->flags |= P2P_DEV_PD_FOR_JOIN;
437	else
438		dev->flags &= ~P2P_DEV_PD_FOR_JOIN;
439
440	if (p2p->state != P2P_IDLE && p2p->state != P2P_SEARCH &&
441	    p2p->state != P2P_LISTEN_ONLY) {
442		wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Busy with other "
443			"operations; postpone Provision Discovery Request "
444			"with " MACSTR " (config methods 0x%x)",
445			MAC2STR(peer_addr), config_methods);
446		return 0;
447	}
448
449	/*
450	 * We use the join param as a cue to differentiate between user
451	 * initiated PD request and one issued during finds (internal).
452	 */
453	p2p->user_initiated_pd = !join;
454
455	if (p2p->user_initiated_pd)
456		p2p->pd_retries = MAX_PROV_DISC_REQ_RETRIES;
457
458	return p2p_send_prov_disc_req(p2p, dev, join, force_freq);
459}
460
461
462void p2p_reset_pending_pd(struct p2p_data *p2p)
463{
464	struct p2p_device *dev;
465
466	dl_list_for_each(dev, &p2p->devices, struct p2p_device, list) {
467		if (os_memcmp(p2p->pending_pd_devaddr,
468			      dev->info.p2p_device_addr, ETH_ALEN))
469			continue;
470		if (!dev->req_config_methods)
471			continue;
472		if (dev->flags & P2P_DEV_PD_FOR_JOIN)
473			continue;
474		/* Reset the config methods of the device */
475		dev->req_config_methods = 0;
476	}
477
478	p2p->user_initiated_pd = 0;
479	os_memset(p2p->pending_pd_devaddr, 0, ETH_ALEN);
480	p2p->pd_retries = 0;
481}
482