xref: /freebsd/contrib/wpa/src/p2p/p2p_go_neg.c (revision f078c492a9b57877c723586db26d789cda1b98ea)
1 /*
2  * Wi-Fi Direct - P2P Group Owner Negotiation
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 "utils/eloop.h"
13 #include "common/ieee802_11_defs.h"
14 #include "common/wpa_ctrl.h"
15 #include "wps/wps_defs.h"
16 #include "p2p_i.h"
17 #include "p2p.h"
18 
19 
20 static int p2p_go_det(u8 own_intent, u8 peer_value)
21 {
22 	u8 peer_intent = peer_value >> 1;
23 	if (own_intent == peer_intent) {
24 		if (own_intent == P2P_MAX_GO_INTENT)
25 			return -1; /* both devices want to become GO */
26 
27 		/* Use tie breaker bit to determine GO */
28 		return (peer_value & 0x01) ? 0 : 1;
29 	}
30 
31 	return own_intent > peer_intent;
32 }
33 
34 
35 int p2p_peer_channels_check(struct p2p_data *p2p, struct p2p_channels *own,
36 			    struct p2p_device *dev,
37 			    const u8 *channel_list, size_t channel_list_len)
38 {
39 	const u8 *pos, *end;
40 	struct p2p_channels *ch;
41 	u8 channels;
42 	struct p2p_channels intersection;
43 
44 	ch = &dev->channels;
45 	os_memset(ch, 0, sizeof(*ch));
46 	pos = channel_list;
47 	end = channel_list + channel_list_len;
48 
49 	if (end - pos < 3)
50 		return -1;
51 	os_memcpy(dev->country, pos, 3);
52 	wpa_hexdump_ascii(MSG_DEBUG, "P2P: Peer country", pos, 3);
53 	if (pos[2] != 0x04 && os_memcmp(pos, p2p->cfg->country, 2) != 0) {
54 		p2p_info(p2p, "Mismatching country (ours=%c%c peer's=%c%c)",
55 			p2p->cfg->country[0], p2p->cfg->country[1],
56 			pos[0], pos[1]);
57 		return -1;
58 	}
59 	pos += 3;
60 
61 	while (end - pos > 2) {
62 		struct p2p_reg_class *cl = &ch->reg_class[ch->reg_classes];
63 		cl->reg_class = *pos++;
64 		channels = *pos++;
65 		if (channels > end - pos) {
66 			p2p_info(p2p, "Invalid peer Channel List");
67 			return -1;
68 		}
69 		cl->channels = channels > P2P_MAX_REG_CLASS_CHANNELS ?
70 			P2P_MAX_REG_CLASS_CHANNELS : channels;
71 		os_memcpy(cl->channel, pos, cl->channels);
72 		pos += channels;
73 		ch->reg_classes++;
74 		if (ch->reg_classes == P2P_MAX_REG_CLASSES)
75 			break;
76 	}
77 
78 	p2p_channels_intersect(own, &dev->channels, &intersection);
79 	p2p_dbg(p2p, "Own reg_classes %d peer reg_classes %d intersection reg_classes %d",
80 		(int) own->reg_classes,
81 		(int) dev->channels.reg_classes,
82 		(int) intersection.reg_classes);
83 	if (intersection.reg_classes == 0) {
84 		p2p_info(p2p, "No common channels found");
85 		return -1;
86 	}
87 	return 0;
88 }
89 
90 
91 static int p2p_peer_channels(struct p2p_data *p2p, struct p2p_device *dev,
92 			     const u8 *channel_list, size_t channel_list_len)
93 {
94 	return p2p_peer_channels_check(p2p, &p2p->channels, dev,
95 				       channel_list, channel_list_len);
96 }
97 
98 
99 u16 p2p_wps_method_pw_id(enum p2p_wps_method wps_method)
100 {
101 	switch (wps_method) {
102 	case WPS_PIN_DISPLAY:
103 		return DEV_PW_REGISTRAR_SPECIFIED;
104 	case WPS_PIN_KEYPAD:
105 		return DEV_PW_USER_SPECIFIED;
106 	case WPS_PBC:
107 		return DEV_PW_PUSHBUTTON;
108 	case WPS_NFC:
109 		return DEV_PW_NFC_CONNECTION_HANDOVER;
110 	case WPS_P2PS:
111 		return DEV_PW_P2PS_DEFAULT;
112 	default:
113 		return DEV_PW_DEFAULT;
114 	}
115 }
116 
117 
118 static const char * p2p_wps_method_str(enum p2p_wps_method wps_method)
119 {
120 	switch (wps_method) {
121 	case WPS_PIN_DISPLAY:
122 		return "Display";
123 	case WPS_PIN_KEYPAD:
124 		return "Keypad";
125 	case WPS_PBC:
126 		return "PBC";
127 	case WPS_NFC:
128 		return "NFC";
129 	case WPS_P2PS:
130 		return "P2PS";
131 	default:
132 		return "??";
133 	}
134 }
135 
136 
137 static struct wpabuf * p2p_build_go_neg_req(struct p2p_data *p2p,
138 					    struct p2p_device *peer)
139 {
140 	struct wpabuf *buf;
141 	u8 *len;
142 	u8 group_capab;
143 	size_t extra = 0;
144 	u16 pw_id;
145 
146 #ifdef CONFIG_WIFI_DISPLAY
147 	if (p2p->wfd_ie_go_neg)
148 		extra = wpabuf_len(p2p->wfd_ie_go_neg);
149 #endif /* CONFIG_WIFI_DISPLAY */
150 
151 	if (p2p->vendor_elem && p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_REQ])
152 		extra += wpabuf_len(p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_REQ]);
153 
154 	buf = wpabuf_alloc(1000 + extra);
155 	if (buf == NULL)
156 		return NULL;
157 
158 	p2p_buf_add_public_action_hdr(buf, P2P_GO_NEG_REQ, peer->dialog_token);
159 
160 	len = p2p_buf_add_ie_hdr(buf);
161 	group_capab = 0;
162 	if (peer->flags & P2P_DEV_PREFER_PERSISTENT_GROUP) {
163 		group_capab |= P2P_GROUP_CAPAB_PERSISTENT_GROUP;
164 		if (peer->flags & P2P_DEV_PREFER_PERSISTENT_RECONN)
165 			group_capab |= P2P_GROUP_CAPAB_PERSISTENT_RECONN;
166 	}
167 	if (p2p->cross_connect)
168 		group_capab |= P2P_GROUP_CAPAB_CROSS_CONN;
169 	if (p2p->cfg->p2p_intra_bss)
170 		group_capab |= P2P_GROUP_CAPAB_INTRA_BSS_DIST;
171 	p2p_buf_add_capability(buf, p2p->dev_capab &
172 			       ~P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY,
173 			       group_capab);
174 	p2p_buf_add_go_intent(buf, (p2p->go_intent << 1) | peer->tie_breaker);
175 	p2p_buf_add_config_timeout(buf, p2p->go_timeout, p2p->client_timeout);
176 	p2p_buf_add_listen_channel(buf, p2p->cfg->country, p2p->cfg->reg_class,
177 				   p2p->cfg->channel);
178 	if (p2p->ext_listen_interval)
179 		p2p_buf_add_ext_listen_timing(buf, p2p->ext_listen_period,
180 					      p2p->ext_listen_interval);
181 	p2p_buf_add_intended_addr(buf, p2p->intended_addr);
182 	p2p_buf_add_channel_list(buf, p2p->cfg->country, &p2p->channels);
183 	p2p_buf_add_device_info(buf, p2p, peer);
184 	p2p_buf_add_operating_channel(buf, p2p->cfg->country,
185 				      p2p->op_reg_class, p2p->op_channel);
186 	p2p_buf_update_ie_hdr(buf, len);
187 
188 	p2p_buf_add_pref_channel_list(buf, p2p->pref_freq_list,
189 				      p2p->num_pref_freq);
190 
191 	/* WPS IE with Device Password ID attribute */
192 	pw_id = p2p_wps_method_pw_id(peer->wps_method);
193 	if (peer->oob_pw_id)
194 		pw_id = peer->oob_pw_id;
195 	if (p2p_build_wps_ie(p2p, buf, pw_id, 0) < 0) {
196 		p2p_dbg(p2p, "Failed to build WPS IE for GO Negotiation Request");
197 		wpabuf_free(buf);
198 		return NULL;
199 	}
200 
201 #ifdef CONFIG_WIFI_DISPLAY
202 	if (p2p->wfd_ie_go_neg)
203 		wpabuf_put_buf(buf, p2p->wfd_ie_go_neg);
204 #endif /* CONFIG_WIFI_DISPLAY */
205 
206 	if (p2p->vendor_elem && p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_REQ])
207 		wpabuf_put_buf(buf, p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_REQ]);
208 
209 	return buf;
210 }
211 
212 
213 int p2p_connect_send(struct p2p_data *p2p, struct p2p_device *dev)
214 {
215 	struct wpabuf *req;
216 	int freq;
217 
218 	if (dev->flags & P2P_DEV_PD_BEFORE_GO_NEG) {
219 		u16 config_method;
220 		p2p_dbg(p2p, "Use PD-before-GO-Neg workaround for " MACSTR,
221 			MAC2STR(dev->info.p2p_device_addr));
222 		if (dev->wps_method == WPS_PIN_DISPLAY)
223 			config_method = WPS_CONFIG_KEYPAD;
224 		else if (dev->wps_method == WPS_PIN_KEYPAD)
225 			config_method = WPS_CONFIG_DISPLAY;
226 		else if (dev->wps_method == WPS_PBC)
227 			config_method = WPS_CONFIG_PUSHBUTTON;
228 		else if (dev->wps_method == WPS_P2PS)
229 			config_method = WPS_CONFIG_P2PS;
230 		else
231 			return -1;
232 		return p2p_prov_disc_req(p2p, dev->info.p2p_device_addr,
233 					 NULL, config_method, 0, 0, 1);
234 	}
235 
236 	freq = dev->listen_freq > 0 ? dev->listen_freq : dev->oper_freq;
237 	if (dev->oob_go_neg_freq > 0)
238 		freq = dev->oob_go_neg_freq;
239 	if (freq <= 0) {
240 		p2p_dbg(p2p, "No Listen/Operating frequency known for the peer "
241 			MACSTR " to send GO Negotiation Request",
242 			MAC2STR(dev->info.p2p_device_addr));
243 		return -1;
244 	}
245 
246 	req = p2p_build_go_neg_req(p2p, dev);
247 	if (req == NULL)
248 		return -1;
249 	p2p_dbg(p2p, "Sending GO Negotiation Request");
250 	p2p_set_state(p2p, P2P_CONNECT);
251 	p2p->pending_action_state = P2P_PENDING_GO_NEG_REQUEST;
252 	p2p->go_neg_peer = dev;
253 	eloop_cancel_timeout(p2p_go_neg_wait_timeout, p2p, NULL);
254 	dev->flags |= P2P_DEV_WAIT_GO_NEG_RESPONSE;
255 	dev->connect_reqs++;
256 	if (p2p_send_action(p2p, freq, dev->info.p2p_device_addr,
257 			    p2p->cfg->dev_addr, dev->info.p2p_device_addr,
258 			    wpabuf_head(req), wpabuf_len(req), 500) < 0) {
259 		p2p_dbg(p2p, "Failed to send Action frame");
260 		/* Use P2P find to recover and retry */
261 		p2p_set_timeout(p2p, 0, 0);
262 	} else
263 		dev->go_neg_req_sent++;
264 
265 	wpabuf_free(req);
266 
267 	return 0;
268 }
269 
270 
271 static struct wpabuf * p2p_build_go_neg_resp(struct p2p_data *p2p,
272 					     struct p2p_device *peer,
273 					     u8 dialog_token, u8 status,
274 					     u8 tie_breaker)
275 {
276 	struct wpabuf *buf;
277 	u8 *len;
278 	u8 group_capab;
279 	size_t extra = 0;
280 	u16 pw_id;
281 
282 	p2p_dbg(p2p, "Building GO Negotiation Response");
283 
284 #ifdef CONFIG_WIFI_DISPLAY
285 	if (p2p->wfd_ie_go_neg)
286 		extra = wpabuf_len(p2p->wfd_ie_go_neg);
287 #endif /* CONFIG_WIFI_DISPLAY */
288 
289 	if (p2p->vendor_elem && p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_RESP])
290 		extra += wpabuf_len(p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_RESP]);
291 
292 	buf = wpabuf_alloc(1000 + extra);
293 	if (buf == NULL)
294 		return NULL;
295 
296 	p2p_buf_add_public_action_hdr(buf, P2P_GO_NEG_RESP, dialog_token);
297 
298 	len = p2p_buf_add_ie_hdr(buf);
299 	p2p_buf_add_status(buf, status);
300 	group_capab = 0;
301 	if (peer && peer->go_state == LOCAL_GO) {
302 		if (peer->flags & P2P_DEV_PREFER_PERSISTENT_GROUP) {
303 			group_capab |= P2P_GROUP_CAPAB_PERSISTENT_GROUP;
304 			if (peer->flags & P2P_DEV_PREFER_PERSISTENT_RECONN)
305 				group_capab |=
306 					P2P_GROUP_CAPAB_PERSISTENT_RECONN;
307 		}
308 		if (p2p->cross_connect)
309 			group_capab |= P2P_GROUP_CAPAB_CROSS_CONN;
310 		if (p2p->cfg->p2p_intra_bss)
311 			group_capab |= P2P_GROUP_CAPAB_INTRA_BSS_DIST;
312 	}
313 	p2p_buf_add_capability(buf, p2p->dev_capab &
314 			       ~P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY,
315 			       group_capab);
316 	p2p_buf_add_go_intent(buf, (p2p->go_intent << 1) | tie_breaker);
317 	p2p_buf_add_config_timeout(buf, p2p->go_timeout, p2p->client_timeout);
318 	if (p2p->override_pref_op_class) {
319 		p2p_dbg(p2p, "Override operating channel preference");
320 		p2p_buf_add_operating_channel(buf, p2p->cfg->country,
321 					      p2p->override_pref_op_class,
322 					      p2p->override_pref_channel);
323 	} else if (peer && peer->go_state == REMOTE_GO && !p2p->num_pref_freq) {
324 		p2p_dbg(p2p, "Omit Operating Channel attribute");
325 	} else {
326 		p2p_buf_add_operating_channel(buf, p2p->cfg->country,
327 					      p2p->op_reg_class,
328 					      p2p->op_channel);
329 	}
330 	p2p_buf_add_intended_addr(buf, p2p->intended_addr);
331 	if (status || peer == NULL) {
332 		p2p_buf_add_channel_list(buf, p2p->cfg->country,
333 					 &p2p->channels);
334 	} else if (peer->go_state == REMOTE_GO) {
335 		p2p_buf_add_channel_list(buf, p2p->cfg->country,
336 					 &p2p->channels);
337 	} else {
338 		struct p2p_channels res;
339 		p2p_channels_intersect(&p2p->channels, &peer->channels,
340 				       &res);
341 		p2p_buf_add_channel_list(buf, p2p->cfg->country, &res);
342 	}
343 	p2p_buf_add_device_info(buf, p2p, peer);
344 	if (peer && peer->go_state == LOCAL_GO) {
345 		p2p_buf_add_group_id(buf, p2p->cfg->dev_addr, p2p->ssid,
346 				     p2p->ssid_len);
347 	}
348 	p2p_buf_update_ie_hdr(buf, len);
349 
350 	/* WPS IE with Device Password ID attribute */
351 	pw_id = p2p_wps_method_pw_id(peer ? peer->wps_method : WPS_NOT_READY);
352 	if (peer && peer->oob_pw_id)
353 		pw_id = peer->oob_pw_id;
354 	if (p2p_build_wps_ie(p2p, buf, pw_id, 0) < 0) {
355 		p2p_dbg(p2p, "Failed to build WPS IE for GO Negotiation Response");
356 		wpabuf_free(buf);
357 		return NULL;
358 	}
359 
360 #ifdef CONFIG_WIFI_DISPLAY
361 	if (p2p->wfd_ie_go_neg)
362 		wpabuf_put_buf(buf, p2p->wfd_ie_go_neg);
363 #endif /* CONFIG_WIFI_DISPLAY */
364 
365 	if (p2p->vendor_elem && p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_RESP])
366 		wpabuf_put_buf(buf, p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_RESP]);
367 
368 	return buf;
369 }
370 
371 
372 /**
373  * p2p_reselect_channel - Re-select operating channel based on peer information
374  * @p2p: P2P module context from p2p_init()
375  * @intersection: Support channel list intersection from local and peer
376  *
377  * This function is used to re-select the best channel after having received
378  * information from the peer to allow supported channel lists to be intersected.
379  * This can be used to improve initial channel selection done in
380  * p2p_prepare_channel() prior to the start of GO Negotiation. In addition, this
381  * can be used for Invitation case.
382  */
383 void p2p_reselect_channel(struct p2p_data *p2p,
384 			  struct p2p_channels *intersection)
385 {
386 	struct p2p_reg_class *cl;
387 	int freq;
388 	u8 op_reg_class, op_channel;
389 	unsigned int i;
390 	const int op_classes_5ghz[] = { 124, 125, 115, 0 };
391 	const int op_classes_ht40[] = { 126, 127, 116, 117, 0 };
392 	const int op_classes_vht[] = { 128, 129, 130, 0 };
393 
394 	if (p2p->own_freq_preference > 0 &&
395 	    p2p_freq_to_channel(p2p->own_freq_preference,
396 				&op_reg_class, &op_channel) == 0 &&
397 	    p2p_channels_includes(intersection, op_reg_class, op_channel)) {
398 		p2p_dbg(p2p, "Pick own channel preference (reg_class %u channel %u) from intersection",
399 			op_reg_class, op_channel);
400 		p2p->op_reg_class = op_reg_class;
401 		p2p->op_channel = op_channel;
402 		return;
403 	}
404 
405 	if (p2p->best_freq_overall > 0 &&
406 	    p2p_freq_to_channel(p2p->best_freq_overall,
407 				&op_reg_class, &op_channel) == 0 &&
408 	    p2p_channels_includes(intersection, op_reg_class, op_channel)) {
409 		p2p_dbg(p2p, "Pick best overall channel (reg_class %u channel %u) from intersection",
410 			op_reg_class, op_channel);
411 		p2p->op_reg_class = op_reg_class;
412 		p2p->op_channel = op_channel;
413 		return;
414 	}
415 
416 	/* First, try to pick the best channel from another band */
417 	freq = p2p_channel_to_freq(p2p->op_reg_class, p2p->op_channel);
418 	if (freq >= 2400 && freq < 2500 && p2p->best_freq_5 > 0 &&
419 	    !p2p_channels_includes(intersection, p2p->op_reg_class,
420 				   p2p->op_channel) &&
421 	    p2p_freq_to_channel(p2p->best_freq_5,
422 				&op_reg_class, &op_channel) == 0 &&
423 	    p2p_channels_includes(intersection, op_reg_class, op_channel)) {
424 		p2p_dbg(p2p, "Pick best 5 GHz channel (reg_class %u channel %u) from intersection",
425 			op_reg_class, op_channel);
426 		p2p->op_reg_class = op_reg_class;
427 		p2p->op_channel = op_channel;
428 		return;
429 	}
430 
431 	if (freq >= 4900 && freq < 6000 && p2p->best_freq_24 > 0 &&
432 	    !p2p_channels_includes(intersection, p2p->op_reg_class,
433 				   p2p->op_channel) &&
434 	    p2p_freq_to_channel(p2p->best_freq_24,
435 				&op_reg_class, &op_channel) == 0 &&
436 	    p2p_channels_includes(intersection, op_reg_class, op_channel)) {
437 		p2p_dbg(p2p, "Pick best 2.4 GHz channel (reg_class %u channel %u) from intersection",
438 			op_reg_class, op_channel);
439 		p2p->op_reg_class = op_reg_class;
440 		p2p->op_channel = op_channel;
441 		return;
442 	}
443 
444 	/* Select channel with highest preference if the peer supports it */
445 	for (i = 0; p2p->cfg->pref_chan && i < p2p->cfg->num_pref_chan; i++) {
446 		if (p2p_channels_includes(intersection,
447 					  p2p->cfg->pref_chan[i].op_class,
448 					  p2p->cfg->pref_chan[i].chan)) {
449 			p2p->op_reg_class = p2p->cfg->pref_chan[i].op_class;
450 			p2p->op_channel = p2p->cfg->pref_chan[i].chan;
451 			p2p_dbg(p2p, "Pick highest preferred channel (op_class %u channel %u) from intersection",
452 				p2p->op_reg_class, p2p->op_channel);
453 			return;
454 		}
455 	}
456 
457 	/* Try a channel where we might be able to use VHT */
458 	if (p2p_channel_select(intersection, op_classes_vht,
459 			       &p2p->op_reg_class, &p2p->op_channel) == 0) {
460 		p2p_dbg(p2p, "Pick possible VHT channel (op_class %u channel %u) from intersection",
461 			p2p->op_reg_class, p2p->op_channel);
462 		return;
463 	}
464 
465 	/* Try a channel where we might be able to use HT40 */
466 	if (p2p_channel_select(intersection, op_classes_ht40,
467 			       &p2p->op_reg_class, &p2p->op_channel) == 0) {
468 		p2p_dbg(p2p, "Pick possible HT40 channel (op_class %u channel %u) from intersection",
469 			p2p->op_reg_class, p2p->op_channel);
470 		return;
471 	}
472 
473 	/* Prefer a 5 GHz channel */
474 	if (p2p_channel_select(intersection, op_classes_5ghz,
475 			       &p2p->op_reg_class, &p2p->op_channel) == 0) {
476 		p2p_dbg(p2p, "Pick possible 5 GHz channel (op_class %u channel %u) from intersection",
477 			p2p->op_reg_class, p2p->op_channel);
478 		return;
479 	}
480 
481 	/*
482 	 * Try to see if the original channel is in the intersection. If
483 	 * so, no need to change anything, as it already contains some
484 	 * randomness.
485 	 */
486 	if (p2p_channels_includes(intersection, p2p->op_reg_class,
487 				  p2p->op_channel)) {
488 		p2p_dbg(p2p, "Using original operating class and channel (op_class %u channel %u) from intersection",
489 			p2p->op_reg_class, p2p->op_channel);
490 		return;
491 	}
492 
493 	/*
494 	 * Fall back to whatever is included in the channel intersection since
495 	 * no better options seems to be available.
496 	 */
497 	cl = &intersection->reg_class[0];
498 	p2p_dbg(p2p, "Pick another channel (reg_class %u channel %u) from intersection",
499 		cl->reg_class, cl->channel[0]);
500 	p2p->op_reg_class = cl->reg_class;
501 	p2p->op_channel = cl->channel[0];
502 }
503 
504 
505 int p2p_go_select_channel(struct p2p_data *p2p, struct p2p_device *dev,
506 			  u8 *status)
507 {
508 	struct p2p_channels tmp, intersection;
509 
510 	p2p_channels_dump(p2p, "own channels", &p2p->channels);
511 	p2p_channels_dump(p2p, "peer channels", &dev->channels);
512 	p2p_channels_intersect(&p2p->channels, &dev->channels, &tmp);
513 	p2p_channels_dump(p2p, "intersection", &tmp);
514 	p2p_channels_remove_freqs(&tmp, &p2p->no_go_freq);
515 	p2p_channels_dump(p2p, "intersection after no-GO removal", &tmp);
516 	p2p_channels_intersect(&tmp, &p2p->cfg->channels, &intersection);
517 	p2p_channels_dump(p2p, "intersection with local channel list",
518 			  &intersection);
519 	if (intersection.reg_classes == 0 ||
520 	    intersection.reg_class[0].channels == 0) {
521 		*status = P2P_SC_FAIL_NO_COMMON_CHANNELS;
522 		p2p_dbg(p2p, "No common channels found");
523 		return -1;
524 	}
525 
526 	if (!p2p_channels_includes(&intersection, p2p->op_reg_class,
527 				   p2p->op_channel)) {
528 		if (dev->flags & P2P_DEV_FORCE_FREQ) {
529 			*status = P2P_SC_FAIL_NO_COMMON_CHANNELS;
530 			p2p_dbg(p2p, "Peer does not support the forced channel");
531 			return -1;
532 		}
533 
534 		p2p_dbg(p2p, "Selected operating channel (op_class %u channel %u) not acceptable to the peer",
535 			p2p->op_reg_class, p2p->op_channel);
536 		p2p_reselect_channel(p2p, &intersection);
537 	} else if (!(dev->flags & P2P_DEV_FORCE_FREQ) &&
538 		   !p2p->cfg->cfg_op_channel) {
539 		p2p_dbg(p2p, "Try to optimize channel selection with peer information received; previously selected op_class %u channel %u",
540 			p2p->op_reg_class, p2p->op_channel);
541 		p2p_reselect_channel(p2p, &intersection);
542 	}
543 
544 	if (!p2p->ssid_set) {
545 		p2p_build_ssid(p2p, p2p->ssid, &p2p->ssid_len);
546 		p2p->ssid_set = 1;
547 	}
548 
549 	return 0;
550 }
551 
552 
553 static void p2p_check_pref_chan_no_recv(struct p2p_data *p2p, int go,
554 					struct p2p_device *dev,
555 					struct p2p_message *msg,
556 					unsigned freq_list[], unsigned int size)
557 {
558 	u8 op_class, op_channel;
559 	unsigned int oper_freq = 0, i, j;
560 	int found = 0;
561 
562 	p2p_dbg(p2p,
563 		"Peer didn't provide a preferred frequency list, see if any of our preferred channels are supported by peer device");
564 
565 	/*
566 	 * Search for a common channel in our preferred frequency list which is
567 	 * also supported by the peer device.
568 	 */
569 	for (i = 0; i < size && !found; i++) {
570 		/* Make sure that the common frequency is supported by peer. */
571 		oper_freq = freq_list[i];
572 		if (p2p_freq_to_channel(oper_freq, &op_class,
573 					&op_channel) < 0)
574 			continue; /* cannot happen due to earlier check */
575 		for (j = 0; j < msg->channel_list_len; j++) {
576 
577 			if (op_channel != msg->channel_list[j])
578 				continue;
579 
580 			p2p->op_reg_class = op_class;
581 			p2p->op_channel = op_channel;
582 			os_memcpy(&p2p->channels, &p2p->cfg->channels,
583 				  sizeof(struct p2p_channels));
584 			found = 1;
585 			break;
586 		}
587 	}
588 
589 	if (found) {
590 		p2p_dbg(p2p,
591 			"Freq %d MHz is a preferred channel and is also supported by peer, use it as the operating channel",
592 			oper_freq);
593 	} else {
594 		p2p_dbg(p2p,
595 			"None of our preferred channels are supported by peer!");
596 	}
597 }
598 
599 
600 static void p2p_check_pref_chan_recv(struct p2p_data *p2p, int go,
601 				     struct p2p_device *dev,
602 				     struct p2p_message *msg,
603 				     unsigned freq_list[], unsigned int size)
604 {
605 	u8 op_class, op_channel;
606 	unsigned int oper_freq = 0, i, j;
607 	int found = 0;
608 
609 	/*
610 	 * Peer device supports a Preferred Frequency List.
611 	 * Search for a common channel in the preferred frequency lists
612 	 * of both peer and local devices.
613 	 */
614 	for (i = 0; i < size && !found; i++) {
615 		for (j = 2; j < (msg->pref_freq_list_len / 2); j++) {
616 			oper_freq = p2p_channel_to_freq(
617 				msg->pref_freq_list[2 * j],
618 				msg->pref_freq_list[2 * j + 1]);
619 			if (freq_list[i] != oper_freq)
620 				continue;
621 			if (p2p_freq_to_channel(oper_freq, &op_class,
622 						&op_channel) < 0)
623 				continue; /* cannot happen */
624 			p2p->op_reg_class = op_class;
625 			p2p->op_channel = op_channel;
626 			os_memcpy(&p2p->channels, &p2p->cfg->channels,
627 				  sizeof(struct p2p_channels));
628 			found = 1;
629 			break;
630 		}
631 	}
632 
633 	if (found) {
634 		p2p_dbg(p2p,
635 			"Freq %d MHz is a common preferred channel for both peer and local, use it as operating channel",
636 			oper_freq);
637 	} else {
638 		p2p_dbg(p2p, "No common preferred channels found!");
639 	}
640 }
641 
642 
643 void p2p_check_pref_chan(struct p2p_data *p2p, int go,
644 			 struct p2p_device *dev, struct p2p_message *msg)
645 {
646 	unsigned int freq_list[P2P_MAX_PREF_CHANNELS], size;
647 	unsigned int i;
648 	u8 op_class, op_channel;
649 	char txt[100], *pos, *end;
650 	int res;
651 
652 	/*
653 	 * Use the preferred channel list from the driver only if there is no
654 	 * forced_freq, e.g., P2P_CONNECT freq=..., and no preferred operating
655 	 * channel hardcoded in the configuration file.
656 	 */
657 	if (!p2p->cfg->get_pref_freq_list || p2p->cfg->num_pref_chan ||
658 	    (dev->flags & P2P_DEV_FORCE_FREQ) || p2p->cfg->cfg_op_channel)
659 		return;
660 
661 	/* Obtain our preferred frequency list from driver based on P2P role. */
662 	size = P2P_MAX_PREF_CHANNELS;
663 	if (p2p->cfg->get_pref_freq_list(p2p->cfg->cb_ctx, go, &size,
664 					 freq_list))
665 		return;
666 	/* Filter out frequencies that are not acceptable for P2P use */
667 	i = 0;
668 	while (i < size) {
669 		if (p2p_freq_to_channel(freq_list[i], &op_class,
670 					&op_channel) < 0 ||
671 		    (!p2p_channels_includes(&p2p->cfg->channels,
672 					    op_class, op_channel) &&
673 		     (go || !p2p_channels_includes(&p2p->cfg->cli_channels,
674 						   op_class, op_channel)))) {
675 			p2p_dbg(p2p,
676 				"Ignore local driver frequency preference %u MHz since it is not acceptable for P2P use (go=%d)",
677 				freq_list[i], go);
678 			if (size - i - 1 > 0)
679 				os_memmove(&freq_list[i], &freq_list[i + 1],
680 					   (size - i - 1) *
681 					   sizeof(unsigned int));
682 			size--;
683 			continue;
684 		}
685 
686 		/* Preferred frequency is acceptable for P2P use */
687 		i++;
688 	}
689 
690 	pos = txt;
691 	end = pos + sizeof(txt);
692 	for (i = 0; i < size; i++) {
693 		res = os_snprintf(pos, end - pos, " %u", freq_list[i]);
694 		if (os_snprintf_error(end - pos, res))
695 			break;
696 		pos += res;
697 	}
698 	*pos = '\0';
699 	p2p_dbg(p2p, "Local driver frequency preference (size=%u):%s",
700 		size, txt);
701 
702 	/*
703 	 * Check if peer's preference of operating channel is in
704 	 * our preferred channel list.
705 	 */
706 	for (i = 0; i < size; i++) {
707 		if (freq_list[i] == (unsigned int) dev->oper_freq)
708 			break;
709 	}
710 	if (i != size &&
711 	    p2p_freq_to_channel(freq_list[i], &op_class, &op_channel) == 0) {
712 		/* Peer operating channel preference matches our preference */
713 		p2p->op_reg_class = op_class;
714 		p2p->op_channel = op_channel;
715 		os_memcpy(&p2p->channels, &p2p->cfg->channels,
716 			  sizeof(struct p2p_channels));
717 		return;
718 	}
719 
720 	p2p_dbg(p2p,
721 		"Peer operating channel preference: %d MHz is not in our preferred channel list",
722 		dev->oper_freq);
723 
724 	/*
725 	  Check if peer's preferred channel list is
726 	  * _not_ included in the GO Negotiation Request or Invitation Request.
727 	  */
728 	if (msg->pref_freq_list_len == 0)
729 		p2p_check_pref_chan_no_recv(p2p, go, dev, msg, freq_list, size);
730 	else
731 		p2p_check_pref_chan_recv(p2p, go, dev, msg, freq_list, size);
732 }
733 
734 
735 void p2p_process_go_neg_req(struct p2p_data *p2p, const u8 *sa,
736 			    const u8 *data, size_t len, int rx_freq)
737 {
738 	struct p2p_device *dev = NULL;
739 	struct wpabuf *resp;
740 	struct p2p_message msg;
741 	u8 status = P2P_SC_FAIL_INVALID_PARAMS;
742 	int tie_breaker = 0;
743 	int freq;
744 
745 	p2p_dbg(p2p, "Received GO Negotiation Request from " MACSTR "(freq=%d)",
746 		MAC2STR(sa), rx_freq);
747 
748 	if (p2p_parse(data, len, &msg))
749 		return;
750 
751 	if (!msg.capability) {
752 		p2p_dbg(p2p, "Mandatory Capability attribute missing from GO Negotiation Request");
753 #ifdef CONFIG_P2P_STRICT
754 		goto fail;
755 #endif /* CONFIG_P2P_STRICT */
756 	}
757 
758 	if (msg.go_intent)
759 		tie_breaker = *msg.go_intent & 0x01;
760 	else {
761 		p2p_dbg(p2p, "Mandatory GO Intent attribute missing from GO Negotiation Request");
762 #ifdef CONFIG_P2P_STRICT
763 		goto fail;
764 #endif /* CONFIG_P2P_STRICT */
765 	}
766 
767 	if (!msg.config_timeout) {
768 		p2p_dbg(p2p, "Mandatory Configuration Timeout attribute missing from GO Negotiation Request");
769 #ifdef CONFIG_P2P_STRICT
770 		goto fail;
771 #endif /* CONFIG_P2P_STRICT */
772 	}
773 
774 	if (!msg.listen_channel) {
775 		p2p_dbg(p2p, "No Listen Channel attribute received");
776 		goto fail;
777 	}
778 	if (!msg.operating_channel) {
779 		p2p_dbg(p2p, "No Operating Channel attribute received");
780 		goto fail;
781 	}
782 	if (!msg.channel_list) {
783 		p2p_dbg(p2p, "No Channel List attribute received");
784 		goto fail;
785 	}
786 	if (!msg.intended_addr) {
787 		p2p_dbg(p2p, "No Intended P2P Interface Address attribute received");
788 		goto fail;
789 	}
790 	if (!msg.p2p_device_info) {
791 		p2p_dbg(p2p, "No P2P Device Info attribute received");
792 		goto fail;
793 	}
794 
795 	if (os_memcmp(msg.p2p_device_addr, sa, ETH_ALEN) != 0) {
796 		p2p_dbg(p2p, "Unexpected GO Negotiation Request SA=" MACSTR
797 			" != dev_addr=" MACSTR,
798 			MAC2STR(sa), MAC2STR(msg.p2p_device_addr));
799 		goto fail;
800 	}
801 
802 	dev = p2p_get_device(p2p, sa);
803 
804 	if (msg.status && *msg.status) {
805 		p2p_dbg(p2p, "Unexpected Status attribute (%d) in GO Negotiation Request",
806 			*msg.status);
807 		if (dev && p2p->go_neg_peer == dev &&
808 		    *msg.status == P2P_SC_FAIL_REJECTED_BY_USER) {
809 			/*
810 			 * This mechanism for using Status attribute in GO
811 			 * Negotiation Request is not compliant with the P2P
812 			 * specification, but some deployed devices use it to
813 			 * indicate rejection of GO Negotiation in a case where
814 			 * they have sent out GO Negotiation Response with
815 			 * status 1. The P2P specification explicitly disallows
816 			 * this. To avoid unnecessary interoperability issues
817 			 * and extra frames, mark the pending negotiation as
818 			 * failed and do not reply to this GO Negotiation
819 			 * Request frame.
820 			 */
821 			p2p->cfg->send_action_done(p2p->cfg->cb_ctx);
822 			p2p_go_neg_failed(p2p, *msg.status);
823 			p2p_parse_free(&msg);
824 			return;
825 		}
826 		goto fail;
827 	}
828 
829 	if (dev == NULL)
830 		dev = p2p_add_dev_from_go_neg_req(p2p, sa, &msg);
831 	else if ((dev->flags & P2P_DEV_PROBE_REQ_ONLY) ||
832 		  !(dev->flags & P2P_DEV_REPORTED))
833 		p2p_add_dev_info(p2p, sa, dev, &msg);
834 	else if (!dev->listen_freq && !dev->oper_freq) {
835 		/*
836 		 * This may happen if the peer entry was added based on PD
837 		 * Request and no Probe Request/Response frame has been received
838 		 * from this peer (or that information has timed out).
839 		 */
840 		p2p_dbg(p2p, "Update peer " MACSTR
841 			" based on GO Neg Req since listen/oper freq not known",
842 			MAC2STR(dev->info.p2p_device_addr));
843 		p2p_add_dev_info(p2p, sa, dev, &msg);
844 	}
845 
846 	if (p2p->go_neg_peer && p2p->go_neg_peer == dev)
847 		eloop_cancel_timeout(p2p_go_neg_wait_timeout, p2p, NULL);
848 
849 	if (dev && dev->flags & P2P_DEV_USER_REJECTED) {
850 		p2p_dbg(p2p, "User has rejected this peer");
851 		status = P2P_SC_FAIL_REJECTED_BY_USER;
852 	} else if (dev == NULL ||
853 		   (dev->wps_method == WPS_NOT_READY &&
854 		    (p2p->authorized_oob_dev_pw_id == 0 ||
855 		     p2p->authorized_oob_dev_pw_id !=
856 		     msg.dev_password_id))) {
857 		p2p_dbg(p2p, "Not ready for GO negotiation with " MACSTR,
858 			MAC2STR(sa));
859 		status = P2P_SC_FAIL_INFO_CURRENTLY_UNAVAILABLE;
860 		p2p->cfg->go_neg_req_rx(p2p->cfg->cb_ctx, sa,
861 					msg.dev_password_id,
862 					msg.go_intent ? (*msg.go_intent >> 1) :
863 					0);
864 	} else if (p2p->go_neg_peer && p2p->go_neg_peer != dev) {
865 		p2p_dbg(p2p, "Already in Group Formation with another peer");
866 		status = P2P_SC_FAIL_UNABLE_TO_ACCOMMODATE;
867 	} else {
868 		int go;
869 
870 		if (!p2p->go_neg_peer) {
871 			p2p_dbg(p2p, "Starting GO Negotiation with previously authorized peer");
872 			if (!(dev->flags & P2P_DEV_FORCE_FREQ)) {
873 				p2p_dbg(p2p, "Use default channel settings");
874 				p2p->op_reg_class = p2p->cfg->op_reg_class;
875 				p2p->op_channel = p2p->cfg->op_channel;
876 				os_memcpy(&p2p->channels, &p2p->cfg->channels,
877 					  sizeof(struct p2p_channels));
878 			} else {
879 				p2p_dbg(p2p, "Use previously configured forced channel settings");
880 			}
881 		}
882 
883 		dev->flags &= ~P2P_DEV_NOT_YET_READY;
884 
885 		if (!msg.go_intent) {
886 			p2p_dbg(p2p, "No GO Intent attribute received");
887 			goto fail;
888 		}
889 		if ((*msg.go_intent >> 1) > P2P_MAX_GO_INTENT) {
890 			p2p_dbg(p2p, "Invalid GO Intent value (%u) received",
891 				*msg.go_intent >> 1);
892 			goto fail;
893 		}
894 
895 		if (dev->go_neg_req_sent &&
896 		    os_memcmp(sa, p2p->cfg->dev_addr, ETH_ALEN) > 0) {
897 			p2p_dbg(p2p, "Do not reply since peer has higher address and GO Neg Request already sent");
898 			p2p_parse_free(&msg);
899 			return;
900 		}
901 
902 		if (dev->go_neg_req_sent &&
903 		    (dev->flags & P2P_DEV_PEER_WAITING_RESPONSE)) {
904 			p2p_dbg(p2p,
905 				"Do not reply since peer is waiting for us to start a new GO Negotiation and GO Neg Request already sent");
906 			p2p_parse_free(&msg);
907 			return;
908 		}
909 
910 		go = p2p_go_det(p2p->go_intent, *msg.go_intent);
911 		if (go < 0) {
912 			p2p_dbg(p2p, "Incompatible GO Intent");
913 			status = P2P_SC_FAIL_BOTH_GO_INTENT_15;
914 			goto fail;
915 		}
916 
917 		if (p2p_peer_channels(p2p, dev, msg.channel_list,
918 				      msg.channel_list_len) < 0) {
919 			p2p_dbg(p2p, "No common channels found");
920 			status = P2P_SC_FAIL_NO_COMMON_CHANNELS;
921 			goto fail;
922 		}
923 
924 		switch (msg.dev_password_id) {
925 		case DEV_PW_REGISTRAR_SPECIFIED:
926 			p2p_dbg(p2p, "PIN from peer Display");
927 			if (dev->wps_method != WPS_PIN_KEYPAD) {
928 				p2p_dbg(p2p, "We have wps_method=%s -> incompatible",
929 					p2p_wps_method_str(dev->wps_method));
930 				status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
931 				goto fail;
932 			}
933 			break;
934 		case DEV_PW_USER_SPECIFIED:
935 			p2p_dbg(p2p, "Peer entered PIN on Keypad");
936 			if (dev->wps_method != WPS_PIN_DISPLAY) {
937 				p2p_dbg(p2p, "We have wps_method=%s -> incompatible",
938 					p2p_wps_method_str(dev->wps_method));
939 				status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
940 				goto fail;
941 			}
942 			break;
943 		case DEV_PW_PUSHBUTTON:
944 			p2p_dbg(p2p, "Peer using pushbutton");
945 			if (dev->wps_method != WPS_PBC) {
946 				p2p_dbg(p2p, "We have wps_method=%s -> incompatible",
947 					p2p_wps_method_str(dev->wps_method));
948 				status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
949 				goto fail;
950 			}
951 			break;
952 		case DEV_PW_P2PS_DEFAULT:
953 			p2p_dbg(p2p, "Peer using P2PS pin");
954 			if (dev->wps_method != WPS_P2PS) {
955 				p2p_dbg(p2p,
956 					"We have wps_method=%s -> incompatible",
957 					p2p_wps_method_str(dev->wps_method));
958 				status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
959 				goto fail;
960 			}
961 			break;
962 		default:
963 			if (msg.dev_password_id &&
964 			    msg.dev_password_id == dev->oob_pw_id) {
965 				p2p_dbg(p2p, "Peer using NFC");
966 				if (dev->wps_method != WPS_NFC) {
967 					p2p_dbg(p2p, "We have wps_method=%s -> incompatible",
968 						p2p_wps_method_str(
969 							dev->wps_method));
970 					status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
971 					goto fail;
972 				}
973 				break;
974 			}
975 #ifdef CONFIG_WPS_NFC
976 			if (p2p->authorized_oob_dev_pw_id &&
977 			    msg.dev_password_id ==
978 			    p2p->authorized_oob_dev_pw_id) {
979 				p2p_dbg(p2p, "Using static handover with our device password from NFC Tag");
980 				dev->wps_method = WPS_NFC;
981 				dev->oob_pw_id = p2p->authorized_oob_dev_pw_id;
982 				break;
983 			}
984 #endif /* CONFIG_WPS_NFC */
985 			p2p_dbg(p2p, "Unsupported Device Password ID %d",
986 				msg.dev_password_id);
987 			status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
988 			goto fail;
989 		}
990 
991 		if (go && p2p_go_select_channel(p2p, dev, &status) < 0)
992 			goto fail;
993 
994 		dev->go_state = go ? LOCAL_GO : REMOTE_GO;
995 		dev->oper_freq = p2p_channel_to_freq(msg.operating_channel[3],
996 						     msg.operating_channel[4]);
997 		p2p_dbg(p2p, "Peer operating channel preference: %d MHz",
998 			dev->oper_freq);
999 
1000 		/*
1001 		 * Use the driver preferred frequency list extension if
1002 		 * supported.
1003 		 */
1004 		p2p_check_pref_chan(p2p, go, dev, &msg);
1005 
1006 		if (msg.config_timeout) {
1007 			dev->go_timeout = msg.config_timeout[0];
1008 			dev->client_timeout = msg.config_timeout[1];
1009 		}
1010 
1011 		p2p_dbg(p2p, "GO Negotiation with " MACSTR, MAC2STR(sa));
1012 		if (p2p->state != P2P_IDLE)
1013 			p2p_stop_find_for_freq(p2p, rx_freq);
1014 		p2p_set_state(p2p, P2P_GO_NEG);
1015 		p2p_clear_timeout(p2p);
1016 		dev->dialog_token = msg.dialog_token;
1017 		os_memcpy(dev->intended_addr, msg.intended_addr, ETH_ALEN);
1018 		p2p->go_neg_peer = dev;
1019 		eloop_cancel_timeout(p2p_go_neg_wait_timeout, p2p, NULL);
1020 		status = P2P_SC_SUCCESS;
1021 	}
1022 
1023 fail:
1024 	if (dev)
1025 		dev->status = status;
1026 	resp = p2p_build_go_neg_resp(p2p, dev, msg.dialog_token, status,
1027 				     !tie_breaker);
1028 	p2p_parse_free(&msg);
1029 	if (resp == NULL)
1030 		return;
1031 	p2p_dbg(p2p, "Sending GO Negotiation Response");
1032 	if (rx_freq > 0)
1033 		freq = rx_freq;
1034 	else
1035 		freq = p2p_channel_to_freq(p2p->cfg->reg_class,
1036 					   p2p->cfg->channel);
1037 	if (freq < 0) {
1038 		p2p_dbg(p2p, "Unknown regulatory class/channel");
1039 		wpabuf_free(resp);
1040 		return;
1041 	}
1042 	if (status == P2P_SC_SUCCESS) {
1043 		p2p->pending_action_state = P2P_PENDING_GO_NEG_RESPONSE;
1044 		dev->flags |= P2P_DEV_WAIT_GO_NEG_CONFIRM;
1045 		if (os_memcmp(sa, p2p->cfg->dev_addr, ETH_ALEN) < 0) {
1046 			/*
1047 			 * Peer has smaller address, so the GO Negotiation
1048 			 * Response from us is expected to complete
1049 			 * negotiation. Ignore a GO Negotiation Response from
1050 			 * the peer if it happens to be received after this
1051 			 * point due to a race condition in GO Negotiation
1052 			 * Request transmission and processing.
1053 			 */
1054 			dev->flags &= ~P2P_DEV_WAIT_GO_NEG_RESPONSE;
1055 		}
1056 	} else
1057 		p2p->pending_action_state =
1058 			P2P_PENDING_GO_NEG_RESPONSE_FAILURE;
1059 	if (p2p_send_action(p2p, freq, sa, p2p->cfg->dev_addr,
1060 			    p2p->cfg->dev_addr,
1061 			    wpabuf_head(resp), wpabuf_len(resp), 100) < 0) {
1062 		p2p_dbg(p2p, "Failed to send Action frame");
1063 	}
1064 
1065 	wpabuf_free(resp);
1066 }
1067 
1068 
1069 static struct wpabuf * p2p_build_go_neg_conf(struct p2p_data *p2p,
1070 					     struct p2p_device *peer,
1071 					     u8 dialog_token, u8 status,
1072 					     const u8 *resp_chan, int go)
1073 {
1074 	struct wpabuf *buf;
1075 	u8 *len;
1076 	struct p2p_channels res;
1077 	u8 group_capab;
1078 	size_t extra = 0;
1079 
1080 	p2p_dbg(p2p, "Building GO Negotiation Confirm");
1081 
1082 #ifdef CONFIG_WIFI_DISPLAY
1083 	if (p2p->wfd_ie_go_neg)
1084 		extra = wpabuf_len(p2p->wfd_ie_go_neg);
1085 #endif /* CONFIG_WIFI_DISPLAY */
1086 
1087 	if (p2p->vendor_elem && p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_CONF])
1088 		extra += wpabuf_len(p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_CONF]);
1089 
1090 	buf = wpabuf_alloc(1000 + extra);
1091 	if (buf == NULL)
1092 		return NULL;
1093 
1094 	p2p_buf_add_public_action_hdr(buf, P2P_GO_NEG_CONF, dialog_token);
1095 
1096 	len = p2p_buf_add_ie_hdr(buf);
1097 	p2p_buf_add_status(buf, status);
1098 	group_capab = 0;
1099 	if (peer->go_state == LOCAL_GO) {
1100 		if (peer->flags & P2P_DEV_PREFER_PERSISTENT_GROUP) {
1101 			group_capab |= P2P_GROUP_CAPAB_PERSISTENT_GROUP;
1102 			if (peer->flags & P2P_DEV_PREFER_PERSISTENT_RECONN)
1103 				group_capab |=
1104 					P2P_GROUP_CAPAB_PERSISTENT_RECONN;
1105 		}
1106 		if (p2p->cross_connect)
1107 			group_capab |= P2P_GROUP_CAPAB_CROSS_CONN;
1108 		if (p2p->cfg->p2p_intra_bss)
1109 			group_capab |= P2P_GROUP_CAPAB_INTRA_BSS_DIST;
1110 	}
1111 	p2p_buf_add_capability(buf, p2p->dev_capab &
1112 			       ~P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY,
1113 			       group_capab);
1114 	if (go || resp_chan == NULL)
1115 		p2p_buf_add_operating_channel(buf, p2p->cfg->country,
1116 					      p2p->op_reg_class,
1117 					      p2p->op_channel);
1118 	else
1119 		p2p_buf_add_operating_channel(buf, (const char *) resp_chan,
1120 					      resp_chan[3], resp_chan[4]);
1121 	p2p_channels_intersect(&p2p->channels, &peer->channels, &res);
1122 	p2p_buf_add_channel_list(buf, p2p->cfg->country, &res);
1123 	if (go) {
1124 		p2p_buf_add_group_id(buf, p2p->cfg->dev_addr, p2p->ssid,
1125 				     p2p->ssid_len);
1126 	}
1127 	p2p_buf_update_ie_hdr(buf, len);
1128 
1129 #ifdef CONFIG_WIFI_DISPLAY
1130 	if (p2p->wfd_ie_go_neg)
1131 		wpabuf_put_buf(buf, p2p->wfd_ie_go_neg);
1132 #endif /* CONFIG_WIFI_DISPLAY */
1133 
1134 	if (p2p->vendor_elem && p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_CONF])
1135 		wpabuf_put_buf(buf, p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_CONF]);
1136 
1137 	return buf;
1138 }
1139 
1140 
1141 void p2p_process_go_neg_resp(struct p2p_data *p2p, const u8 *sa,
1142 			     const u8 *data, size_t len, int rx_freq)
1143 {
1144 	struct p2p_device *dev;
1145 	int go = -1;
1146 	struct p2p_message msg;
1147 	u8 status = P2P_SC_SUCCESS;
1148 	int freq;
1149 
1150 	p2p_dbg(p2p, "Received GO Negotiation Response from " MACSTR
1151 		" (freq=%d)", MAC2STR(sa), rx_freq);
1152 	dev = p2p_get_device(p2p, sa);
1153 	if (dev == NULL || dev->wps_method == WPS_NOT_READY ||
1154 	    dev != p2p->go_neg_peer) {
1155 		p2p_dbg(p2p, "Not ready for GO negotiation with " MACSTR,
1156 			MAC2STR(sa));
1157 		return;
1158 	}
1159 
1160 	if (p2p_parse(data, len, &msg))
1161 		return;
1162 
1163 	if (!(dev->flags & P2P_DEV_WAIT_GO_NEG_RESPONSE)) {
1164 		p2p_dbg(p2p, "Was not expecting GO Negotiation Response - ignore");
1165 		p2p_parse_free(&msg);
1166 		return;
1167 	}
1168 	dev->flags &= ~P2P_DEV_WAIT_GO_NEG_RESPONSE;
1169 
1170 	if (msg.dialog_token != dev->dialog_token) {
1171 		p2p_dbg(p2p, "Unexpected Dialog Token %u (expected %u)",
1172 			msg.dialog_token, dev->dialog_token);
1173 		p2p_parse_free(&msg);
1174 		return;
1175 	}
1176 
1177 	if (!msg.status) {
1178 		p2p_dbg(p2p, "No Status attribute received");
1179 		status = P2P_SC_FAIL_INVALID_PARAMS;
1180 		goto fail;
1181 	}
1182 	if (*msg.status) {
1183 		p2p_dbg(p2p, "GO Negotiation rejected: status %d", *msg.status);
1184 		dev->go_neg_req_sent = 0;
1185 		if (*msg.status == P2P_SC_FAIL_INFO_CURRENTLY_UNAVAILABLE) {
1186 			p2p_dbg(p2p, "Wait for the peer to become ready for GO Negotiation");
1187 			dev->flags |= P2P_DEV_NOT_YET_READY;
1188 			eloop_cancel_timeout(p2p_go_neg_wait_timeout, p2p,
1189 					     NULL);
1190 			eloop_register_timeout(120, 0, p2p_go_neg_wait_timeout,
1191 					       p2p, NULL);
1192 			if (p2p->state == P2P_CONNECT_LISTEN)
1193 				p2p_set_state(p2p, P2P_WAIT_PEER_CONNECT);
1194 			else
1195 				p2p_set_state(p2p, P2P_WAIT_PEER_IDLE);
1196 			p2p_set_timeout(p2p, 0, 0);
1197 		} else {
1198 			p2p_dbg(p2p, "Stop GO Negotiation attempt");
1199 			p2p_go_neg_failed(p2p, *msg.status);
1200 		}
1201 		p2p->cfg->send_action_done(p2p->cfg->cb_ctx);
1202 		p2p_parse_free(&msg);
1203 		return;
1204 	}
1205 
1206 	if (!msg.capability) {
1207 		p2p_dbg(p2p, "Mandatory Capability attribute missing from GO Negotiation Response");
1208 #ifdef CONFIG_P2P_STRICT
1209 		status = P2P_SC_FAIL_INVALID_PARAMS;
1210 		goto fail;
1211 #endif /* CONFIG_P2P_STRICT */
1212 	}
1213 
1214 	if (!msg.p2p_device_info) {
1215 		p2p_dbg(p2p, "Mandatory P2P Device Info attribute missing from GO Negotiation Response");
1216 #ifdef CONFIG_P2P_STRICT
1217 		status = P2P_SC_FAIL_INVALID_PARAMS;
1218 		goto fail;
1219 #endif /* CONFIG_P2P_STRICT */
1220 	}
1221 
1222 	if (!msg.intended_addr) {
1223 		p2p_dbg(p2p, "No Intended P2P Interface Address attribute received");
1224 		status = P2P_SC_FAIL_INVALID_PARAMS;
1225 		goto fail;
1226 	}
1227 
1228 	if (!msg.go_intent) {
1229 		p2p_dbg(p2p, "No GO Intent attribute received");
1230 		status = P2P_SC_FAIL_INVALID_PARAMS;
1231 		goto fail;
1232 	}
1233 	if ((*msg.go_intent >> 1) > P2P_MAX_GO_INTENT) {
1234 		p2p_dbg(p2p, "Invalid GO Intent value (%u) received",
1235 			*msg.go_intent >> 1);
1236 		status = P2P_SC_FAIL_INVALID_PARAMS;
1237 		goto fail;
1238 	}
1239 
1240 	go = p2p_go_det(p2p->go_intent, *msg.go_intent);
1241 	if (go < 0) {
1242 		p2p_dbg(p2p, "Incompatible GO Intent");
1243 		status = P2P_SC_FAIL_INCOMPATIBLE_PARAMS;
1244 		goto fail;
1245 	}
1246 
1247 	if (!go && msg.group_id) {
1248 		/* Store SSID for Provisioning step */
1249 		p2p->ssid_len = msg.group_id_len - ETH_ALEN;
1250 		os_memcpy(p2p->ssid, msg.group_id + ETH_ALEN, p2p->ssid_len);
1251 	} else if (!go) {
1252 		p2p_dbg(p2p, "Mandatory P2P Group ID attribute missing from GO Negotiation Response");
1253 		p2p->ssid_len = 0;
1254 		status = P2P_SC_FAIL_INVALID_PARAMS;
1255 		goto fail;
1256 	}
1257 
1258 	if (!msg.config_timeout) {
1259 		p2p_dbg(p2p, "Mandatory Configuration Timeout attribute missing from GO Negotiation Response");
1260 #ifdef CONFIG_P2P_STRICT
1261 		status = P2P_SC_FAIL_INVALID_PARAMS;
1262 		goto fail;
1263 #endif /* CONFIG_P2P_STRICT */
1264 	} else {
1265 		dev->go_timeout = msg.config_timeout[0];
1266 		dev->client_timeout = msg.config_timeout[1];
1267 	}
1268 
1269 	if (msg.wfd_subelems) {
1270 		wpabuf_free(dev->info.wfd_subelems);
1271 		dev->info.wfd_subelems = wpabuf_dup(msg.wfd_subelems);
1272 	}
1273 
1274 	if (!msg.operating_channel && !go) {
1275 		/*
1276 		 * Note: P2P Client may omit Operating Channel attribute to
1277 		 * indicate it does not have a preference.
1278 		 */
1279 		p2p_dbg(p2p, "No Operating Channel attribute received");
1280 		status = P2P_SC_FAIL_INVALID_PARAMS;
1281 		goto fail;
1282 	}
1283 	if (!msg.channel_list) {
1284 		p2p_dbg(p2p, "No Channel List attribute received");
1285 		status = P2P_SC_FAIL_INVALID_PARAMS;
1286 		goto fail;
1287 	}
1288 
1289 	if (p2p_peer_channels(p2p, dev, msg.channel_list,
1290 			      msg.channel_list_len) < 0) {
1291 		p2p_dbg(p2p, "No common channels found");
1292 		status = P2P_SC_FAIL_NO_COMMON_CHANNELS;
1293 		goto fail;
1294 	}
1295 
1296 	if (msg.operating_channel) {
1297 		dev->oper_freq = p2p_channel_to_freq(msg.operating_channel[3],
1298 						     msg.operating_channel[4]);
1299 		p2p_dbg(p2p, "Peer operating channel preference: %d MHz",
1300 			dev->oper_freq);
1301 	} else
1302 		dev->oper_freq = 0;
1303 
1304 	switch (msg.dev_password_id) {
1305 	case DEV_PW_REGISTRAR_SPECIFIED:
1306 		p2p_dbg(p2p, "PIN from peer Display");
1307 		if (dev->wps_method != WPS_PIN_KEYPAD) {
1308 			p2p_dbg(p2p, "We have wps_method=%s -> incompatible",
1309 				p2p_wps_method_str(dev->wps_method));
1310 			status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
1311 			goto fail;
1312 		}
1313 		break;
1314 	case DEV_PW_USER_SPECIFIED:
1315 		p2p_dbg(p2p, "Peer entered PIN on Keypad");
1316 		if (dev->wps_method != WPS_PIN_DISPLAY) {
1317 			p2p_dbg(p2p, "We have wps_method=%s -> incompatible",
1318 				p2p_wps_method_str(dev->wps_method));
1319 			status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
1320 			goto fail;
1321 		}
1322 		break;
1323 	case DEV_PW_PUSHBUTTON:
1324 		p2p_dbg(p2p, "Peer using pushbutton");
1325 		if (dev->wps_method != WPS_PBC) {
1326 			p2p_dbg(p2p, "We have wps_method=%s -> incompatible",
1327 				p2p_wps_method_str(dev->wps_method));
1328 			status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
1329 			goto fail;
1330 		}
1331 		break;
1332 	case DEV_PW_P2PS_DEFAULT:
1333 		p2p_dbg(p2p, "P2P: Peer using P2PS default pin");
1334 		if (dev->wps_method != WPS_P2PS) {
1335 			p2p_dbg(p2p, "We have wps_method=%s -> incompatible",
1336 				p2p_wps_method_str(dev->wps_method));
1337 			status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
1338 			goto fail;
1339 		}
1340 		break;
1341 	default:
1342 		if (msg.dev_password_id &&
1343 		    msg.dev_password_id == dev->oob_pw_id) {
1344 			p2p_dbg(p2p, "Peer using NFC");
1345 			if (dev->wps_method != WPS_NFC) {
1346 				p2p_dbg(p2p, "We have wps_method=%s -> incompatible",
1347 					p2p_wps_method_str(dev->wps_method));
1348 				status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
1349 				goto fail;
1350 			}
1351 			break;
1352 		}
1353 		p2p_dbg(p2p, "Unsupported Device Password ID %d",
1354 			msg.dev_password_id);
1355 		status = P2P_SC_FAIL_INCOMPATIBLE_PROV_METHOD;
1356 		goto fail;
1357 	}
1358 
1359 	if (go && p2p_go_select_channel(p2p, dev, &status) < 0)
1360 		goto fail;
1361 
1362 	/*
1363 	 * Use the driver preferred frequency list extension if local device is
1364 	 * GO.
1365 	 */
1366 	if (go)
1367 		p2p_check_pref_chan(p2p, go, dev, &msg);
1368 
1369 	p2p_set_state(p2p, P2P_GO_NEG);
1370 	p2p_clear_timeout(p2p);
1371 
1372 	p2p_dbg(p2p, "GO Negotiation with " MACSTR, MAC2STR(sa));
1373 	os_memcpy(dev->intended_addr, msg.intended_addr, ETH_ALEN);
1374 
1375 fail:
1376 	/* Store GO Negotiation Confirmation to allow retransmission */
1377 	wpabuf_free(dev->go_neg_conf);
1378 	dev->go_neg_conf = p2p_build_go_neg_conf(p2p, dev, msg.dialog_token,
1379 						 status, msg.operating_channel,
1380 						 go);
1381 	p2p_parse_free(&msg);
1382 	if (dev->go_neg_conf == NULL)
1383 		return;
1384 	p2p_dbg(p2p, "Sending GO Negotiation Confirm");
1385 	if (status == P2P_SC_SUCCESS) {
1386 		p2p->pending_action_state = P2P_PENDING_GO_NEG_CONFIRM;
1387 		dev->go_state = go ? LOCAL_GO : REMOTE_GO;
1388 	} else
1389 		p2p->pending_action_state = P2P_NO_PENDING_ACTION;
1390 	if (rx_freq > 0)
1391 		freq = rx_freq;
1392 	else
1393 		freq = dev->listen_freq;
1394 
1395 	dev->go_neg_conf_freq = freq;
1396 	dev->go_neg_conf_sent = 0;
1397 
1398 	if (p2p_send_action(p2p, freq, sa, p2p->cfg->dev_addr, sa,
1399 			    wpabuf_head(dev->go_neg_conf),
1400 			    wpabuf_len(dev->go_neg_conf), 50) < 0) {
1401 		p2p_dbg(p2p, "Failed to send Action frame");
1402 		p2p_go_neg_failed(p2p, -1);
1403 		p2p->cfg->send_action_done(p2p->cfg->cb_ctx);
1404 	} else
1405 		dev->go_neg_conf_sent++;
1406 	if (status != P2P_SC_SUCCESS) {
1407 		p2p_dbg(p2p, "GO Negotiation failed");
1408 		p2p_go_neg_failed(p2p, status);
1409 	}
1410 }
1411 
1412 
1413 void p2p_process_go_neg_conf(struct p2p_data *p2p, const u8 *sa,
1414 			     const u8 *data, size_t len)
1415 {
1416 	struct p2p_device *dev;
1417 	struct p2p_message msg;
1418 
1419 	p2p_dbg(p2p, "Received GO Negotiation Confirm from " MACSTR,
1420 		MAC2STR(sa));
1421 	dev = p2p_get_device(p2p, sa);
1422 	if (dev == NULL || dev->wps_method == WPS_NOT_READY ||
1423 	    dev != p2p->go_neg_peer) {
1424 		p2p_dbg(p2p, "Not ready for GO negotiation with " MACSTR,
1425 			MAC2STR(sa));
1426 		return;
1427 	}
1428 
1429 	if (p2p->pending_action_state == P2P_PENDING_GO_NEG_RESPONSE) {
1430 		p2p_dbg(p2p, "Stopped waiting for TX status on GO Negotiation Response since we already received Confirmation");
1431 		p2p->pending_action_state = P2P_NO_PENDING_ACTION;
1432 	}
1433 
1434 	if (p2p_parse(data, len, &msg))
1435 		return;
1436 
1437 	if (!(dev->flags & P2P_DEV_WAIT_GO_NEG_CONFIRM)) {
1438 		p2p_dbg(p2p, "Was not expecting GO Negotiation Confirm - ignore");
1439 		p2p_parse_free(&msg);
1440 		return;
1441 	}
1442 	dev->flags &= ~P2P_DEV_WAIT_GO_NEG_CONFIRM;
1443 	p2p->cfg->send_action_done(p2p->cfg->cb_ctx);
1444 
1445 	if (msg.dialog_token != dev->dialog_token) {
1446 		p2p_dbg(p2p, "Unexpected Dialog Token %u (expected %u)",
1447 			msg.dialog_token, dev->dialog_token);
1448 		p2p_parse_free(&msg);
1449 		return;
1450 	}
1451 
1452 	if (!msg.status) {
1453 		p2p_dbg(p2p, "No Status attribute received");
1454 		p2p_parse_free(&msg);
1455 		return;
1456 	}
1457 	if (*msg.status) {
1458 		p2p_dbg(p2p, "GO Negotiation rejected: status %d", *msg.status);
1459 		p2p_go_neg_failed(p2p, *msg.status);
1460 		p2p_parse_free(&msg);
1461 		return;
1462 	}
1463 
1464 	if (dev->go_state == REMOTE_GO && msg.group_id) {
1465 		/* Store SSID for Provisioning step */
1466 		p2p->ssid_len = msg.group_id_len - ETH_ALEN;
1467 		os_memcpy(p2p->ssid, msg.group_id + ETH_ALEN, p2p->ssid_len);
1468 	} else if (dev->go_state == REMOTE_GO) {
1469 		p2p_dbg(p2p, "Mandatory P2P Group ID attribute missing from GO Negotiation Confirmation");
1470 		p2p->ssid_len = 0;
1471 		p2p_go_neg_failed(p2p, P2P_SC_FAIL_INVALID_PARAMS);
1472 		p2p_parse_free(&msg);
1473 		return;
1474 	}
1475 
1476 	if (!msg.operating_channel) {
1477 		p2p_dbg(p2p, "Mandatory Operating Channel attribute missing from GO Negotiation Confirmation");
1478 #ifdef CONFIG_P2P_STRICT
1479 		p2p_parse_free(&msg);
1480 		return;
1481 #endif /* CONFIG_P2P_STRICT */
1482 	} else if (dev->go_state == REMOTE_GO) {
1483 		int oper_freq = p2p_channel_to_freq(msg.operating_channel[3],
1484 						    msg.operating_channel[4]);
1485 		if (oper_freq != dev->oper_freq) {
1486 			p2p_dbg(p2p, "Updated peer (GO) operating channel preference from %d MHz to %d MHz",
1487 				dev->oper_freq, oper_freq);
1488 			dev->oper_freq = oper_freq;
1489 		}
1490 	}
1491 
1492 	if (!msg.channel_list) {
1493 		p2p_dbg(p2p, "Mandatory Operating Channel attribute missing from GO Negotiation Confirmation");
1494 #ifdef CONFIG_P2P_STRICT
1495 		p2p_parse_free(&msg);
1496 		return;
1497 #endif /* CONFIG_P2P_STRICT */
1498 	}
1499 
1500 	p2p_parse_free(&msg);
1501 
1502 	if (dev->go_state == UNKNOWN_GO) {
1503 		/*
1504 		 * This should not happen since GO negotiation has already
1505 		 * been completed.
1506 		 */
1507 		p2p_dbg(p2p, "Unexpected GO Neg state - do not know which end becomes GO");
1508 		return;
1509 	}
1510 
1511 	/*
1512 	 * The peer could have missed our ctrl::ack frame for GO Negotiation
1513 	 * Confirm and continue retransmitting the frame. To reduce the
1514 	 * likelihood of the peer not getting successful TX status for the
1515 	 * GO Negotiation Confirm frame, wait a short time here before starting
1516 	 * the group so that we will remain on the current channel to
1517 	 * acknowledge any possible retransmission from the peer.
1518 	 */
1519 	p2p_dbg(p2p, "20 ms wait on current channel before starting group");
1520 	os_sleep(0, 20000);
1521 
1522 	p2p_go_complete(p2p, dev);
1523 }
1524