xref: /freebsd/contrib/wpa/src/p2p/p2p_sd.c (revision 96190b4fef3b4a0cc3ca0606b0c4e3e69a5e6717)
1 /*
2  * Wi-Fi Direct - P2P service discovery
3  * Copyright (c) 2009, 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/gas.h"
14 #include "p2p_i.h"
15 #include "p2p.h"
16 
17 
18 #ifdef CONFIG_WIFI_DISPLAY
19 static int wfd_wsd_supported(struct wpabuf *wfd)
20 {
21 	const u8 *pos, *end;
22 	u8 subelem;
23 	u16 len;
24 
25 	if (wfd == NULL)
26 		return 0;
27 
28 	pos = wpabuf_head(wfd);
29 	end = pos + wpabuf_len(wfd);
30 
31 	while (end - pos >= 3) {
32 		subelem = *pos++;
33 		len = WPA_GET_BE16(pos);
34 		pos += 2;
35 		if (len > end - pos)
36 			break;
37 
38 		if (subelem == WFD_SUBELEM_DEVICE_INFO && len >= 6) {
39 			u16 info = WPA_GET_BE16(pos);
40 			return !!(info & 0x0040);
41 		}
42 
43 		pos += len;
44 	}
45 
46 	return 0;
47 }
48 #endif /* CONFIG_WIFI_DISPLAY */
49 
50 struct p2p_sd_query * p2p_pending_sd_req(struct p2p_data *p2p,
51 					 struct p2p_device *dev)
52 {
53 	struct p2p_sd_query *q;
54 	int wsd = 0;
55 	int count = 0;
56 
57 	if (!(dev->info.dev_capab & P2P_DEV_CAPAB_SERVICE_DISCOVERY))
58 		return NULL; /* peer does not support SD */
59 #ifdef CONFIG_WIFI_DISPLAY
60 	if (wfd_wsd_supported(dev->info.wfd_subelems))
61 		wsd = 1;
62 #endif /* CONFIG_WIFI_DISPLAY */
63 
64 	for (q = p2p->sd_queries; q; q = q->next) {
65 		/* Use WSD only if the peer indicates support or it */
66 		if (q->wsd && !wsd)
67 			continue;
68 		/* if the query is a broadcast query */
69 		if (q->for_all_peers) {
70 			/*
71 			 * check if there are any broadcast queries pending for
72 			 * this device
73 			 */
74 			if (dev->sd_pending_bcast_queries <= 0)
75 				return NULL;
76 			/* query number that needs to be send to the device */
77 			if (count == dev->sd_pending_bcast_queries - 1)
78 				goto found;
79 			count++;
80 		}
81 		if (!q->for_all_peers &&
82 		    ether_addr_equal(q->peer, dev->info.p2p_device_addr))
83 			goto found;
84 	}
85 
86 	return NULL;
87 
88 found:
89 	if (dev->sd_reqs > 100) {
90 		p2p_dbg(p2p, "Too many SD request attempts to " MACSTR
91 			" - skip remaining queries",
92 			MAC2STR(dev->info.p2p_device_addr));
93 		return NULL;
94 	}
95 	return q;
96 }
97 
98 
99 static void p2p_decrease_sd_bc_queries(struct p2p_data *p2p, int query_number)
100 {
101 	struct p2p_device *dev;
102 
103 	p2p->num_p2p_sd_queries--;
104 	dl_list_for_each(dev, &p2p->devices, struct p2p_device, list) {
105 		if (query_number <= dev->sd_pending_bcast_queries - 1) {
106 			/*
107 			 * Query not yet sent to the device and it is to be
108 			 * removed, so update the pending count.
109 			*/
110 			dev->sd_pending_bcast_queries--;
111 		}
112 	}
113 }
114 
115 
116 static int p2p_unlink_sd_query(struct p2p_data *p2p,
117 			       struct p2p_sd_query *query)
118 {
119 	struct p2p_sd_query *q, *prev;
120 	int query_number = 0;
121 
122 	q = p2p->sd_queries;
123 	prev = NULL;
124 	while (q) {
125 		if (q == query) {
126 			/* If the query is a broadcast query, decrease one from
127 			 * all the devices */
128 			if (query->for_all_peers)
129 				p2p_decrease_sd_bc_queries(p2p, query_number);
130 			if (prev)
131 				prev->next = q->next;
132 			else
133 				p2p->sd_queries = q->next;
134 			if (p2p->sd_query == query)
135 				p2p->sd_query = NULL;
136 			return 1;
137 		}
138 		if (q->for_all_peers)
139 			query_number++;
140 		prev = q;
141 		q = q->next;
142 	}
143 	return 0;
144 }
145 
146 
147 static void p2p_free_sd_query(struct p2p_sd_query *q)
148 {
149 	if (q == NULL)
150 		return;
151 	wpabuf_free(q->tlvs);
152 	os_free(q);
153 }
154 
155 
156 void p2p_free_sd_queries(struct p2p_data *p2p)
157 {
158 	struct p2p_sd_query *q, *prev;
159 	q = p2p->sd_queries;
160 	p2p->sd_queries = NULL;
161 	while (q) {
162 		prev = q;
163 		q = q->next;
164 		p2p_free_sd_query(prev);
165 	}
166 	p2p->num_p2p_sd_queries = 0;
167 }
168 
169 
170 static struct wpabuf * p2p_build_sd_query(u16 update_indic,
171 					  struct wpabuf *tlvs)
172 {
173 	struct wpabuf *buf;
174 	u8 *len_pos;
175 
176 	buf = gas_anqp_build_initial_req(0, 100 + wpabuf_len(tlvs));
177 	if (buf == NULL)
178 		return NULL;
179 
180 	/* ANQP Query Request Frame */
181 	len_pos = gas_anqp_add_element(buf, ANQP_VENDOR_SPECIFIC);
182 	wpabuf_put_be32(buf, P2P_IE_VENDOR_TYPE);
183 	wpabuf_put_le16(buf, update_indic); /* Service Update Indicator */
184 	wpabuf_put_buf(buf, tlvs);
185 	gas_anqp_set_element_len(buf, len_pos);
186 
187 	gas_anqp_set_len(buf);
188 
189 	return buf;
190 }
191 
192 
193 static void p2p_send_gas_comeback_req(struct p2p_data *p2p, const u8 *dst,
194 				      u8 dialog_token, int freq)
195 {
196 	struct wpabuf *req;
197 
198 	req = gas_build_comeback_req(dialog_token);
199 	if (req == NULL)
200 		return;
201 
202 	p2p->pending_action_state = P2P_NO_PENDING_ACTION;
203 	if (p2p_send_action(p2p, freq, dst, p2p->cfg->dev_addr, dst,
204 			    wpabuf_head(req), wpabuf_len(req), 200) < 0)
205 		p2p_dbg(p2p, "Failed to send Action frame");
206 
207 	wpabuf_free(req);
208 }
209 
210 
211 static struct wpabuf * p2p_build_sd_response(u8 dialog_token, u16 status_code,
212 					     u16 comeback_delay,
213 					     u16 update_indic,
214 					     const struct wpabuf *tlvs)
215 {
216 	struct wpabuf *buf;
217 	u8 *len_pos;
218 
219 	buf = gas_anqp_build_initial_resp(dialog_token, status_code,
220 					  comeback_delay,
221 					  100 + (tlvs ? wpabuf_len(tlvs) : 0));
222 	if (buf == NULL)
223 		return NULL;
224 
225 	if (tlvs) {
226 		/* ANQP Query Response Frame */
227 		len_pos = gas_anqp_add_element(buf, ANQP_VENDOR_SPECIFIC);
228 		wpabuf_put_be32(buf, P2P_IE_VENDOR_TYPE);
229 		 /* Service Update Indicator */
230 		wpabuf_put_le16(buf, update_indic);
231 		wpabuf_put_buf(buf, tlvs);
232 		gas_anqp_set_element_len(buf, len_pos);
233 	}
234 
235 	gas_anqp_set_len(buf);
236 
237 	return buf;
238 }
239 
240 
241 static struct wpabuf * p2p_build_gas_comeback_resp(u8 dialog_token,
242 						   u16 status_code,
243 						   u16 update_indic,
244 						   const u8 *data, size_t len,
245 						   u8 frag_id, u8 more,
246 						   u16 total_len)
247 {
248 	struct wpabuf *buf;
249 
250 	buf = gas_anqp_build_comeback_resp(dialog_token, status_code, frag_id,
251 					   more, 0, 100 + len);
252 	if (buf == NULL)
253 		return NULL;
254 
255 	if (frag_id == 0) {
256 		/* ANQP Query Response Frame */
257 		wpabuf_put_le16(buf, ANQP_VENDOR_SPECIFIC); /* Info ID */
258 		wpabuf_put_le16(buf, 3 + 1 + 2 + total_len);
259 		wpabuf_put_be32(buf, P2P_IE_VENDOR_TYPE);
260 		/* Service Update Indicator */
261 		wpabuf_put_le16(buf, update_indic);
262 	}
263 
264 	wpabuf_put_data(buf, data, len);
265 	gas_anqp_set_len(buf);
266 
267 	return buf;
268 }
269 
270 
271 int p2p_start_sd(struct p2p_data *p2p, struct p2p_device *dev)
272 {
273 	struct wpabuf *req;
274 	int ret = 0;
275 	struct p2p_sd_query *query;
276 	int freq;
277 	unsigned int wait_time;
278 
279 	freq = dev->listen_freq > 0 ? dev->listen_freq : dev->oper_freq;
280 	if (freq <= 0) {
281 		p2p_dbg(p2p, "No Listen/Operating frequency known for the peer "
282 			MACSTR " to send SD Request",
283 			MAC2STR(dev->info.p2p_device_addr));
284 		return -1;
285 	}
286 
287 	query = p2p_pending_sd_req(p2p, dev);
288 	if (query == NULL)
289 		return -1;
290 	if (p2p->state == P2P_SEARCH &&
291 	    ether_addr_equal(p2p->sd_query_no_ack, dev->info.p2p_device_addr)) {
292 		p2p_dbg(p2p, "Do not start Service Discovery with " MACSTR
293 			" due to it being the first no-ACK peer in this search iteration",
294 			MAC2STR(dev->info.p2p_device_addr));
295 		return -2;
296 	}
297 
298 	p2p_dbg(p2p, "Start Service Discovery with " MACSTR,
299 		MAC2STR(dev->info.p2p_device_addr));
300 
301 	req = p2p_build_sd_query(p2p->srv_update_indic, query->tlvs);
302 	if (req == NULL)
303 		return -1;
304 
305 	dev->sd_reqs++;
306 	p2p->sd_peer = dev;
307 	p2p->sd_query = query;
308 	p2p->pending_action_state = P2P_PENDING_SD;
309 
310 	wait_time = 5000;
311 	if (p2p->cfg->max_listen && wait_time > p2p->cfg->max_listen)
312 		wait_time = p2p->cfg->max_listen;
313 	if (p2p_send_action(p2p, freq, dev->info.p2p_device_addr,
314 			    p2p->cfg->dev_addr, dev->info.p2p_device_addr,
315 			    wpabuf_head(req), wpabuf_len(req), wait_time) < 0) {
316 		p2p_dbg(p2p, "Failed to send Action frame");
317 		ret = -1;
318 	}
319 
320 	wpabuf_free(req);
321 
322 	return ret;
323 }
324 
325 
326 void p2p_rx_gas_initial_req(struct p2p_data *p2p, const u8 *sa,
327 			    const u8 *data, size_t len, int rx_freq)
328 {
329 	const u8 *pos = data;
330 	const u8 *end = data + len;
331 	const u8 *next;
332 	u8 dialog_token;
333 	u16 slen;
334 	int freq;
335 	u16 update_indic;
336 
337 
338 	if (p2p->cfg->sd_request == NULL)
339 		return;
340 
341 	if (rx_freq > 0)
342 		freq = rx_freq;
343 	else
344 		freq = p2p_channel_to_freq(p2p->cfg->reg_class,
345 					   p2p->cfg->channel);
346 	if (freq < 0)
347 		return;
348 
349 	if (len < 1 + 2)
350 		return;
351 
352 	dialog_token = *pos++;
353 	p2p_dbg(p2p, "GAS Initial Request from " MACSTR
354 		" (dialog token %u, freq %d)",
355 		MAC2STR(sa), dialog_token, rx_freq);
356 
357 	if (*pos != WLAN_EID_ADV_PROTO) {
358 		p2p_dbg(p2p, "Unexpected IE in GAS Initial Request: %u", *pos);
359 		return;
360 	}
361 	pos++;
362 
363 	slen = *pos++;
364 	if (slen > end - pos || slen < 2) {
365 		p2p_dbg(p2p, "Invalid IE in GAS Initial Request");
366 		return;
367 	}
368 	next = pos + slen;
369 	pos++; /* skip QueryRespLenLimit and PAME-BI */
370 
371 	if (*pos != ACCESS_NETWORK_QUERY_PROTOCOL) {
372 		p2p_dbg(p2p, "Unsupported GAS advertisement protocol id %u",
373 			*pos);
374 		return;
375 	}
376 
377 	pos = next;
378 	/* Query Request */
379 	if (end - pos < 2)
380 		return;
381 	slen = WPA_GET_LE16(pos);
382 	pos += 2;
383 	if (slen > end - pos)
384 		return;
385 	end = pos + slen;
386 
387 	/* ANQP Query Request */
388 	if (end - pos < 4)
389 		return;
390 	if (WPA_GET_LE16(pos) != ANQP_VENDOR_SPECIFIC) {
391 		p2p_dbg(p2p, "Unsupported ANQP Info ID %u", WPA_GET_LE16(pos));
392 		return;
393 	}
394 	pos += 2;
395 
396 	slen = WPA_GET_LE16(pos);
397 	pos += 2;
398 	if (slen > end - pos || slen < 3 + 1) {
399 		p2p_dbg(p2p, "Invalid ANQP Query Request length");
400 		return;
401 	}
402 
403 	if (WPA_GET_BE32(pos) != P2P_IE_VENDOR_TYPE) {
404 		p2p_dbg(p2p, "Unsupported ANQP vendor OUI-type %08x",
405 			WPA_GET_BE32(pos));
406 		return;
407 	}
408 	pos += 4;
409 
410 	if (end - pos < 2)
411 		return;
412 	update_indic = WPA_GET_LE16(pos);
413 	p2p_dbg(p2p, "Service Update Indicator: %u", update_indic);
414 	pos += 2;
415 
416 	p2p->cfg->sd_request(p2p->cfg->cb_ctx, freq, sa, dialog_token,
417 			     update_indic, pos, end - pos);
418 	/* the response will be indicated with a call to p2p_sd_response() */
419 }
420 
421 
422 void p2p_sd_response(struct p2p_data *p2p, int freq, const u8 *dst,
423 		     u8 dialog_token, const struct wpabuf *resp_tlvs)
424 {
425 	struct wpabuf *resp;
426 	size_t max_len;
427 	unsigned int wait_time = 200;
428 
429 	/*
430 	 * In the 60 GHz, we have a smaller maximum frame length for management
431 	 * frames.
432 	 */
433 	max_len = (freq > 56160) ? 928 : 1400;
434 
435 	/* TODO: fix the length limit to match with the maximum frame length */
436 	if (wpabuf_len(resp_tlvs) > max_len) {
437 		p2p_dbg(p2p, "SD response long enough to require fragmentation");
438 		if (p2p->sd_resp) {
439 			/*
440 			 * TODO: Could consider storing the fragmented response
441 			 * separately for each peer to avoid having to drop old
442 			 * one if there is more than one pending SD query.
443 			 * Though, that would eat more memory, so there are
444 			 * also benefits to just using a single buffer.
445 			 */
446 			p2p_dbg(p2p, "Drop previous SD response");
447 			wpabuf_free(p2p->sd_resp);
448 		}
449 		p2p->sd_resp = wpabuf_dup(resp_tlvs);
450 		if (p2p->sd_resp == NULL) {
451 			p2p_err(p2p, "Failed to allocate SD response fragmentation area");
452 			return;
453 		}
454 		os_memcpy(p2p->sd_resp_addr, dst, ETH_ALEN);
455 		p2p->sd_resp_dialog_token = dialog_token;
456 		p2p->sd_resp_pos = 0;
457 		p2p->sd_frag_id = 0;
458 		resp = p2p_build_sd_response(dialog_token, WLAN_STATUS_SUCCESS,
459 					     1, p2p->srv_update_indic, NULL);
460 	} else {
461 		p2p_dbg(p2p, "SD response fits in initial response");
462 		wait_time = 0; /* no more SD frames in the sequence */
463 		resp = p2p_build_sd_response(dialog_token,
464 					     WLAN_STATUS_SUCCESS, 0,
465 					     p2p->srv_update_indic, resp_tlvs);
466 	}
467 	if (resp == NULL)
468 		return;
469 
470 	p2p->pending_action_state = P2P_NO_PENDING_ACTION;
471 	if (p2p_send_action(p2p, freq, dst, p2p->cfg->dev_addr,
472 			    p2p->cfg->dev_addr,
473 			    wpabuf_head(resp), wpabuf_len(resp), wait_time) < 0)
474 		p2p_dbg(p2p, "Failed to send Action frame");
475 
476 	wpabuf_free(resp);
477 }
478 
479 
480 void p2p_rx_gas_initial_resp(struct p2p_data *p2p, const u8 *sa,
481 			     const u8 *data, size_t len, int rx_freq)
482 {
483 	const u8 *pos = data;
484 	const u8 *end = data + len;
485 	const u8 *next;
486 	u8 dialog_token;
487 	u16 status_code;
488 	u16 comeback_delay;
489 	u16 slen;
490 	u16 update_indic;
491 
492 	if ((p2p->state != P2P_SD_DURING_FIND && p2p->state != P2P_SEARCH) ||
493 	    !p2p->sd_peer ||
494 	    !ether_addr_equal(sa, p2p->sd_peer->info.p2p_device_addr)) {
495 		p2p_dbg(p2p, "Ignore unexpected GAS Initial Response from "
496 			MACSTR, MAC2STR(sa));
497 		return;
498 	}
499 	if (p2p->state == P2P_SEARCH) {
500 		/* It is possible for the TX status and RX response events to be
501 		 * reordered, so assume the request was ACKed if a response is
502 		 * received. */
503 		p2p_dbg(p2p,
504 			"GAS Initial Request had not yet received TX status - process the response anyway");
505 		p2p_sd_query_cb(p2p, 1);
506 	}
507 	p2p->cfg->send_action_done(p2p->cfg->cb_ctx);
508 	p2p_clear_timeout(p2p);
509 
510 	p2p_dbg(p2p, "Received GAS Initial Response from " MACSTR " (len=%d)",
511 		MAC2STR(sa), (int) len);
512 
513 	if (len < 5 + 2) {
514 		p2p_dbg(p2p, "Too short GAS Initial Response frame");
515 		return;
516 	}
517 
518 	dialog_token = *pos++;
519 	/* TODO: check dialog_token match */
520 	status_code = WPA_GET_LE16(pos);
521 	pos += 2;
522 	comeback_delay = WPA_GET_LE16(pos);
523 	pos += 2;
524 	p2p_dbg(p2p, "dialog_token=%u status_code=%u comeback_delay=%u",
525 		dialog_token, status_code, comeback_delay);
526 	if (status_code) {
527 		p2p_dbg(p2p, "Service Discovery failed: status code %u",
528 			status_code);
529 		return;
530 	}
531 
532 	if (*pos != WLAN_EID_ADV_PROTO) {
533 		p2p_dbg(p2p, "Unexpected IE in GAS Initial Response: %u", *pos);
534 		return;
535 	}
536 	pos++;
537 
538 	slen = *pos++;
539 	if (slen > end - pos || slen < 2) {
540 		p2p_dbg(p2p, "Invalid IE in GAS Initial Response");
541 		return;
542 	}
543 	next = pos + slen;
544 	pos++; /* skip QueryRespLenLimit and PAME-BI */
545 
546 	if (*pos != ACCESS_NETWORK_QUERY_PROTOCOL) {
547 		p2p_dbg(p2p, "Unsupported GAS advertisement protocol id %u",
548 			*pos);
549 		return;
550 	}
551 
552 	pos = next;
553 	/* Query Response */
554 	if (end - pos < 2) {
555 		p2p_dbg(p2p, "Too short Query Response");
556 		return;
557 	}
558 	slen = WPA_GET_LE16(pos);
559 	pos += 2;
560 	p2p_dbg(p2p, "Query Response Length: %d", slen);
561 	if (slen > end - pos) {
562 		p2p_dbg(p2p, "Not enough Query Response data");
563 		return;
564 	}
565 	end = pos + slen;
566 
567 	if (comeback_delay) {
568 		p2p_dbg(p2p, "Fragmented response - request fragments");
569 		if (p2p->sd_rx_resp) {
570 			p2p_dbg(p2p, "Drop old SD reassembly buffer");
571 			wpabuf_free(p2p->sd_rx_resp);
572 			p2p->sd_rx_resp = NULL;
573 		}
574 		p2p_send_gas_comeback_req(p2p, sa, dialog_token, rx_freq);
575 		return;
576 	}
577 
578 	/* ANQP Query Response */
579 	if (end - pos < 4)
580 		return;
581 	if (WPA_GET_LE16(pos) != ANQP_VENDOR_SPECIFIC) {
582 		p2p_dbg(p2p, "Unsupported ANQP Info ID %u", WPA_GET_LE16(pos));
583 		return;
584 	}
585 	pos += 2;
586 
587 	slen = WPA_GET_LE16(pos);
588 	pos += 2;
589 	if (slen > end - pos || slen < 3 + 1) {
590 		p2p_dbg(p2p, "Invalid ANQP Query Response length");
591 		return;
592 	}
593 
594 	if (WPA_GET_BE32(pos) != P2P_IE_VENDOR_TYPE) {
595 		p2p_dbg(p2p, "Unsupported ANQP vendor OUI-type %08x",
596 			WPA_GET_BE32(pos));
597 		return;
598 	}
599 	pos += 4;
600 
601 	if (end - pos < 2)
602 		return;
603 	update_indic = WPA_GET_LE16(pos);
604 	p2p_dbg(p2p, "Service Update Indicator: %u", update_indic);
605 	pos += 2;
606 
607 	p2p->sd_peer = NULL;
608 
609 	if (p2p->sd_query) {
610 		if (!p2p->sd_query->for_all_peers) {
611 			struct p2p_sd_query *q;
612 			p2p_dbg(p2p, "Remove completed SD query %p",
613 				p2p->sd_query);
614 			q = p2p->sd_query;
615 			p2p_unlink_sd_query(p2p, p2p->sd_query);
616 			p2p_free_sd_query(q);
617 		}
618 		p2p->sd_query = NULL;
619 	}
620 
621 	if (p2p->cfg->sd_response)
622 		p2p->cfg->sd_response(p2p->cfg->cb_ctx, sa, update_indic,
623 				      pos, end - pos);
624 	p2p_continue_find(p2p);
625 }
626 
627 
628 void p2p_rx_gas_comeback_req(struct p2p_data *p2p, const u8 *sa,
629 			     const u8 *data, size_t len, int rx_freq)
630 {
631 	struct wpabuf *resp;
632 	u8 dialog_token;
633 	size_t frag_len, max_len;
634 	int more = 0;
635 	unsigned int wait_time = 200;
636 
637 	wpa_hexdump(MSG_DEBUG, "P2P: RX GAS Comeback Request", data, len);
638 	if (len < 1)
639 		return;
640 	dialog_token = *data;
641 	p2p_dbg(p2p, "Dialog Token: %u", dialog_token);
642 	if (dialog_token != p2p->sd_resp_dialog_token) {
643 		p2p_dbg(p2p, "No pending SD response fragment for dialog token %u",
644 			dialog_token);
645 		return;
646 	}
647 
648 	if (p2p->sd_resp == NULL) {
649 		p2p_dbg(p2p, "No pending SD response fragment available");
650 		return;
651 	}
652 	if (!ether_addr_equal(sa, p2p->sd_resp_addr)) {
653 		p2p_dbg(p2p, "No pending SD response fragment for " MACSTR,
654 			MAC2STR(sa));
655 		return;
656 	}
657 
658 	/*
659 	 * In the 60 GHz, we have a smaller maximum frame length for management
660 	 * frames.
661 	 */
662 	max_len = (rx_freq > 56160) ? 928 : 1400;
663 	frag_len = wpabuf_len(p2p->sd_resp) - p2p->sd_resp_pos;
664 	if (frag_len > max_len) {
665 		frag_len = max_len;
666 		more = 1;
667 	}
668 	resp = p2p_build_gas_comeback_resp(dialog_token, WLAN_STATUS_SUCCESS,
669 					   p2p->srv_update_indic,
670 					   wpabuf_head_u8(p2p->sd_resp) +
671 					   p2p->sd_resp_pos, frag_len,
672 					   p2p->sd_frag_id, more,
673 					   wpabuf_len(p2p->sd_resp));
674 	if (resp == NULL)
675 		return;
676 	p2p_dbg(p2p, "Send GAS Comeback Response (frag_id %d more=%d frag_len=%d)",
677 		p2p->sd_frag_id, more, (int) frag_len);
678 	p2p->sd_frag_id++;
679 	p2p->sd_resp_pos += frag_len;
680 
681 	if (more) {
682 		p2p_dbg(p2p, "%d more bytes remain to be sent",
683 			(int) (wpabuf_len(p2p->sd_resp) - p2p->sd_resp_pos));
684 	} else {
685 		p2p_dbg(p2p, "All fragments of SD response sent");
686 		wpabuf_free(p2p->sd_resp);
687 		p2p->sd_resp = NULL;
688 		wait_time = 0; /* no more SD frames in the sequence */
689 	}
690 
691 	p2p->pending_action_state = P2P_NO_PENDING_ACTION;
692 	if (p2p_send_action(p2p, rx_freq, sa, p2p->cfg->dev_addr,
693 			    p2p->cfg->dev_addr,
694 			    wpabuf_head(resp), wpabuf_len(resp), wait_time) < 0)
695 		p2p_dbg(p2p, "Failed to send Action frame");
696 
697 	wpabuf_free(resp);
698 }
699 
700 
701 void p2p_rx_gas_comeback_resp(struct p2p_data *p2p, const u8 *sa,
702 			      const u8 *data, size_t len, int rx_freq)
703 {
704 	const u8 *pos = data;
705 	const u8 *end = data + len;
706 	const u8 *next;
707 	u8 dialog_token;
708 	u16 status_code;
709 	u8 frag_id;
710 	u8 more_frags;
711 	u16 comeback_delay;
712 	u16 slen;
713 
714 	wpa_hexdump(MSG_DEBUG, "P2P: RX GAS Comeback Response", data, len);
715 
716 	if (p2p->state != P2P_SD_DURING_FIND || p2p->sd_peer == NULL ||
717 	    !ether_addr_equal(sa, p2p->sd_peer->info.p2p_device_addr)) {
718 		p2p_dbg(p2p, "Ignore unexpected GAS Comeback Response from "
719 			MACSTR, MAC2STR(sa));
720 		return;
721 	}
722 	p2p->cfg->send_action_done(p2p->cfg->cb_ctx);
723 	p2p_clear_timeout(p2p);
724 
725 	p2p_dbg(p2p, "Received GAS Comeback Response from " MACSTR " (len=%d)",
726 		MAC2STR(sa), (int) len);
727 
728 	if (len < 6 + 2) {
729 		p2p_dbg(p2p, "Too short GAS Comeback Response frame");
730 		return;
731 	}
732 
733 	dialog_token = *pos++;
734 	/* TODO: check dialog_token match */
735 	status_code = WPA_GET_LE16(pos);
736 	pos += 2;
737 	frag_id = *pos & 0x7f;
738 	more_frags = (*pos & 0x80) >> 7;
739 	pos++;
740 	comeback_delay = WPA_GET_LE16(pos);
741 	pos += 2;
742 	p2p_dbg(p2p, "dialog_token=%u status_code=%u frag_id=%d more_frags=%d "
743 		"comeback_delay=%u",
744 		dialog_token, status_code, frag_id, more_frags,
745 		comeback_delay);
746 	/* TODO: check frag_id match */
747 	if (status_code) {
748 		p2p_dbg(p2p, "Service Discovery failed: status code %u",
749 			status_code);
750 		return;
751 	}
752 
753 	if (*pos != WLAN_EID_ADV_PROTO) {
754 		p2p_dbg(p2p, "Unexpected IE in GAS Comeback Response: %u",
755 			*pos);
756 		return;
757 	}
758 	pos++;
759 
760 	slen = *pos++;
761 	if (slen > end - pos || slen < 2) {
762 		p2p_dbg(p2p, "Invalid IE in GAS Comeback Response");
763 		return;
764 	}
765 	next = pos + slen;
766 	pos++; /* skip QueryRespLenLimit and PAME-BI */
767 
768 	if (*pos != ACCESS_NETWORK_QUERY_PROTOCOL) {
769 		p2p_dbg(p2p, "Unsupported GAS advertisement protocol id %u",
770 			*pos);
771 		return;
772 	}
773 
774 	pos = next;
775 	/* Query Response */
776 	if (end - pos < 2) {
777 		p2p_dbg(p2p, "Too short Query Response");
778 		return;
779 	}
780 	slen = WPA_GET_LE16(pos);
781 	pos += 2;
782 	p2p_dbg(p2p, "Query Response Length: %d", slen);
783 	if (slen > end - pos) {
784 		p2p_dbg(p2p, "Not enough Query Response data");
785 		return;
786 	}
787 	if (slen == 0) {
788 		p2p_dbg(p2p, "No Query Response data");
789 		return;
790 	}
791 	end = pos + slen;
792 
793 	if (p2p->sd_rx_resp) {
794 		 /*
795 		  * ANQP header is only included in the first fragment; rest of
796 		  * the fragments start with continue TLVs.
797 		  */
798 		goto skip_nqp_header;
799 	}
800 
801 	/* ANQP Query Response */
802 	if (end - pos < 4)
803 		return;
804 	if (WPA_GET_LE16(pos) != ANQP_VENDOR_SPECIFIC) {
805 		p2p_dbg(p2p, "Unsupported ANQP Info ID %u", WPA_GET_LE16(pos));
806 		return;
807 	}
808 	pos += 2;
809 
810 	slen = WPA_GET_LE16(pos);
811 	pos += 2;
812 	p2p_dbg(p2p, "ANQP Query Response length: %u", slen);
813 	if (slen < 3 + 1) {
814 		p2p_dbg(p2p, "Invalid ANQP Query Response length");
815 		return;
816 	}
817 	if (end - pos < 4)
818 		return;
819 
820 	if (WPA_GET_BE32(pos) != P2P_IE_VENDOR_TYPE) {
821 		p2p_dbg(p2p, "Unsupported ANQP vendor OUI-type %08x",
822 			WPA_GET_BE32(pos));
823 		return;
824 	}
825 	pos += 4;
826 
827 	if (end - pos < 2)
828 		return;
829 	p2p->sd_rx_update_indic = WPA_GET_LE16(pos);
830 	p2p_dbg(p2p, "Service Update Indicator: %u", p2p->sd_rx_update_indic);
831 	pos += 2;
832 
833 skip_nqp_header:
834 	if (wpabuf_resize(&p2p->sd_rx_resp, end - pos) < 0)
835 		return;
836 	wpabuf_put_data(p2p->sd_rx_resp, pos, end - pos);
837 	p2p_dbg(p2p, "Current SD reassembly buffer length: %u",
838 		(unsigned int) wpabuf_len(p2p->sd_rx_resp));
839 
840 	if (more_frags) {
841 		p2p_dbg(p2p, "More fragments remains");
842 		/* TODO: what would be a good size limit? */
843 		if (wpabuf_len(p2p->sd_rx_resp) > 64000) {
844 			wpabuf_free(p2p->sd_rx_resp);
845 			p2p->sd_rx_resp = NULL;
846 			p2p_dbg(p2p, "Too long SD response - drop it");
847 			return;
848 		}
849 		p2p_send_gas_comeback_req(p2p, sa, dialog_token, rx_freq);
850 		return;
851 	}
852 
853 	p2p->sd_peer = NULL;
854 
855 	if (p2p->sd_query) {
856 		if (!p2p->sd_query->for_all_peers) {
857 			struct p2p_sd_query *q;
858 			p2p_dbg(p2p, "Remove completed SD query %p",
859 				p2p->sd_query);
860 			q = p2p->sd_query;
861 			p2p_unlink_sd_query(p2p, p2p->sd_query);
862 			p2p_free_sd_query(q);
863 		}
864 		p2p->sd_query = NULL;
865 	}
866 
867 	if (p2p->cfg->sd_response)
868 		p2p->cfg->sd_response(p2p->cfg->cb_ctx, sa,
869 				      p2p->sd_rx_update_indic,
870 				      wpabuf_head(p2p->sd_rx_resp),
871 				      wpabuf_len(p2p->sd_rx_resp));
872 	wpabuf_free(p2p->sd_rx_resp);
873 	p2p->sd_rx_resp = NULL;
874 
875 	p2p_continue_find(p2p);
876 }
877 
878 
879 void * p2p_sd_request(struct p2p_data *p2p, const u8 *dst,
880 		      const struct wpabuf *tlvs)
881 {
882 	struct p2p_sd_query *q;
883 
884 	q = os_zalloc(sizeof(*q));
885 	if (q == NULL)
886 		return NULL;
887 
888 	if (dst)
889 		os_memcpy(q->peer, dst, ETH_ALEN);
890 	else
891 		q->for_all_peers = 1;
892 
893 	q->tlvs = wpabuf_dup(tlvs);
894 	if (q->tlvs == NULL) {
895 		p2p_free_sd_query(q);
896 		return NULL;
897 	}
898 
899 	q->next = p2p->sd_queries;
900 	p2p->sd_queries = q;
901 	p2p_dbg(p2p, "Added SD Query %p", q);
902 
903 	if (dst == NULL) {
904 		struct p2p_device *dev;
905 
906 		p2p->num_p2p_sd_queries++;
907 
908 		/* Update all the devices for the newly added broadcast query */
909 		dl_list_for_each(dev, &p2p->devices, struct p2p_device, list) {
910 			if (dev->sd_pending_bcast_queries <= 0)
911 				dev->sd_pending_bcast_queries = 1;
912 			else
913 				dev->sd_pending_bcast_queries++;
914 		}
915 	}
916 
917 	return q;
918 }
919 
920 
921 #ifdef CONFIG_WIFI_DISPLAY
922 void * p2p_sd_request_wfd(struct p2p_data *p2p, const u8 *dst,
923 			  const struct wpabuf *tlvs)
924 {
925 	struct p2p_sd_query *q;
926 	q = p2p_sd_request(p2p, dst, tlvs);
927 	if (q)
928 		q->wsd = 1;
929 	return q;
930 }
931 #endif /* CONFIG_WIFI_DISPLAY */
932 
933 
934 void p2p_sd_service_update(struct p2p_data *p2p)
935 {
936 	p2p->srv_update_indic++;
937 }
938 
939 
940 int p2p_sd_cancel_request(struct p2p_data *p2p, void *req)
941 {
942 	if (p2p_unlink_sd_query(p2p, req)) {
943 		p2p_dbg(p2p, "Cancel pending SD query %p", req);
944 		p2p_free_sd_query(req);
945 		return 0;
946 	}
947 	return -1;
948 }
949