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      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 (pos + 3 <= end) {
     32 		subelem = *pos++;
     33 		len = WPA_GET_BE16(pos);
     34 		pos += 2;
     35 		if (pos + len > end)
     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 
     56 	if (!(dev->info.dev_capab & P2P_DEV_CAPAB_SERVICE_DISCOVERY))
     57 		return NULL; /* peer does not support SD */
     58 #ifdef CONFIG_WIFI_DISPLAY
     59 	if (wfd_wsd_supported(dev->info.wfd_subelems))
     60 		wsd = 1;
     61 #endif /* CONFIG_WIFI_DISPLAY */
     62 
     63 	for (q = p2p->sd_queries; q; q = q->next) {
     64 		/* Use WSD only if the peer indicates support or it */
     65 		if (q->wsd && !wsd)
     66 			continue;
     67 		if (q->for_all_peers && !(dev->flags & P2P_DEV_SD_INFO))
     68 			return q;
     69 		if (!q->for_all_peers &&
     70 		    os_memcmp(q->peer, dev->info.p2p_device_addr, ETH_ALEN) ==
     71 		    0)
     72 			return q;
     73 	}
     74 
     75 	return NULL;
     76 }
     77 
     78 
     79 static int p2p_unlink_sd_query(struct p2p_data *p2p,
     80 			       struct p2p_sd_query *query)
     81 {
     82 	struct p2p_sd_query *q, *prev;
     83 	q = p2p->sd_queries;
     84 	prev = NULL;
     85 	while (q) {
     86 		if (q == query) {
     87 			if (prev)
     88 				prev->next = q->next;
     89 			else
     90 				p2p->sd_queries = q->next;
     91 			if (p2p->sd_query == query)
     92 				p2p->sd_query = NULL;
     93 			return 1;
     94 		}
     95 		prev = q;
     96 		q = q->next;
     97 	}
     98 	return 0;
     99 }
    100 
    101 
    102 static void p2p_free_sd_query(struct p2p_sd_query *q)
    103 {
    104 	if (q == NULL)
    105 		return;
    106 	wpabuf_free(q->tlvs);
    107 	os_free(q);
    108 }
    109 
    110 
    111 void p2p_free_sd_queries(struct p2p_data *p2p)
    112 {
    113 	struct p2p_sd_query *q, *prev;
    114 	q = p2p->sd_queries;
    115 	p2p->sd_queries = NULL;
    116 	while (q) {
    117 		prev = q;
    118 		q = q->next;
    119 		p2p_free_sd_query(prev);
    120 	}
    121 }
    122 
    123 
    124 static struct wpabuf * p2p_build_sd_query(u16 update_indic,
    125 					  struct wpabuf *tlvs)
    126 {
    127 	struct wpabuf *buf;
    128 	u8 *len_pos;
    129 
    130 	buf = gas_anqp_build_initial_req(0, 100 + wpabuf_len(tlvs));
    131 	if (buf == NULL)
    132 		return NULL;
    133 
    134 	/* ANQP Query Request Frame */
    135 	len_pos = gas_anqp_add_element(buf, ANQP_VENDOR_SPECIFIC);
    136 	wpabuf_put_be24(buf, OUI_WFA);
    137 	wpabuf_put_u8(buf, P2P_OUI_TYPE);
    138 	wpabuf_put_le16(buf, update_indic); /* Service Update Indicator */
    139 	wpabuf_put_buf(buf, tlvs);
    140 	gas_anqp_set_element_len(buf, len_pos);
    141 
    142 	gas_anqp_set_len(buf);
    143 
    144 	return buf;
    145 }
    146 
    147 
    148 static void p2p_send_gas_comeback_req(struct p2p_data *p2p, const u8 *dst,
    149 				      u8 dialog_token, int freq)
    150 {
    151 	struct wpabuf *req;
    152 
    153 	req = gas_build_comeback_req(dialog_token);
    154 	if (req == NULL)
    155 		return;
    156 
    157 	p2p->pending_action_state = P2P_NO_PENDING_ACTION;
    158 	if (p2p_send_action(p2p, freq, dst, p2p->cfg->dev_addr, dst,
    159 			    wpabuf_head(req), wpabuf_len(req), 200) < 0)
    160 		p2p_dbg(p2p, "Failed to send Action frame");
    161 
    162 	wpabuf_free(req);
    163 }
    164 
    165 
    166 static struct wpabuf * p2p_build_sd_response(u8 dialog_token, u16 status_code,
    167 					     u16 comeback_delay,
    168 					     u16 update_indic,
    169 					     const struct wpabuf *tlvs)
    170 {
    171 	struct wpabuf *buf;
    172 	u8 *len_pos;
    173 
    174 	buf = gas_anqp_build_initial_resp(dialog_token, status_code,
    175 					  comeback_delay,
    176 					  100 + (tlvs ? wpabuf_len(tlvs) : 0));
    177 	if (buf == NULL)
    178 		return NULL;
    179 
    180 	if (tlvs) {
    181 		/* ANQP Query Response Frame */
    182 		len_pos = gas_anqp_add_element(buf, ANQP_VENDOR_SPECIFIC);
    183 		wpabuf_put_be24(buf, OUI_WFA);
    184 		wpabuf_put_u8(buf, P2P_OUI_TYPE);
    185 		 /* Service Update Indicator */
    186 		wpabuf_put_le16(buf, update_indic);
    187 		wpabuf_put_buf(buf, tlvs);
    188 		gas_anqp_set_element_len(buf, len_pos);
    189 	}
    190 
    191 	gas_anqp_set_len(buf);
    192 
    193 	return buf;
    194 }
    195 
    196 
    197 static struct wpabuf * p2p_build_gas_comeback_resp(u8 dialog_token,
    198 						   u16 status_code,
    199 						   u16 update_indic,
    200 						   const u8 *data, size_t len,
    201 						   u8 frag_id, u8 more,
    202 						   u16 total_len)
    203 {
    204 	struct wpabuf *buf;
    205 
    206 	buf = gas_anqp_build_comeback_resp(dialog_token, status_code, frag_id,
    207 					   more, 0, 100 + len);
    208 	if (buf == NULL)
    209 		return NULL;
    210 
    211 	if (frag_id == 0) {
    212 		/* ANQP Query Response Frame */
    213 		wpabuf_put_le16(buf, ANQP_VENDOR_SPECIFIC); /* Info ID */
    214 		wpabuf_put_le16(buf, 3 + 1 + 2 + total_len);
    215 		wpabuf_put_be24(buf, OUI_WFA);
    216 		wpabuf_put_u8(buf, P2P_OUI_TYPE);
    217 		/* Service Update Indicator */
    218 		wpabuf_put_le16(buf, update_indic);
    219 	}
    220 
    221 	wpabuf_put_data(buf, data, len);
    222 	gas_anqp_set_len(buf);
    223 
    224 	return buf;
    225 }
    226 
    227 
    228 int p2p_start_sd(struct p2p_data *p2p, struct p2p_device *dev)
    229 {
    230 	struct wpabuf *req;
    231 	int ret = 0;
    232 	struct p2p_sd_query *query;
    233 	int freq;
    234 
    235 	freq = dev->listen_freq > 0 ? dev->listen_freq : dev->oper_freq;
    236 	if (freq <= 0) {
    237 		p2p_dbg(p2p, "No Listen/Operating frequency known for the peer "
    238 			MACSTR " to send SD Request",
    239 			MAC2STR(dev->info.p2p_device_addr));
    240 		return -1;
    241 	}
    242 
    243 	query = p2p_pending_sd_req(p2p, dev);
    244 	if (query == NULL)
    245 		return -1;
    246 
    247 	p2p_dbg(p2p, "Start Service Discovery with " MACSTR,
    248 		MAC2STR(dev->info.p2p_device_addr));
    249 
    250 	req = p2p_build_sd_query(p2p->srv_update_indic, query->tlvs);
    251 	if (req == NULL)
    252 		return -1;
    253 
    254 	p2p->sd_peer = dev;
    255 	p2p->sd_query = query;
    256 	p2p->pending_action_state = P2P_PENDING_SD;
    257 
    258 	if (p2p_send_action(p2p, freq, dev->info.p2p_device_addr,
    259 			    p2p->cfg->dev_addr, dev->info.p2p_device_addr,
    260 			    wpabuf_head(req), wpabuf_len(req), 5000) < 0) {
    261 		p2p_dbg(p2p, "Failed to send Action frame");
    262 		ret = -1;
    263 	}
    264 
    265 	wpabuf_free(req);
    266 
    267 	return ret;
    268 }
    269 
    270 
    271 void p2p_rx_gas_initial_req(struct p2p_data *p2p, const u8 *sa,
    272 			    const u8 *data, size_t len, int rx_freq)
    273 {
    274 	const u8 *pos = data;
    275 	const u8 *end = data + len;
    276 	const u8 *next;
    277 	u8 dialog_token;
    278 	u16 slen;
    279 	int freq;
    280 	u16 update_indic;
    281 
    282 
    283 	if (p2p->cfg->sd_request == NULL)
    284 		return;
    285 
    286 	if (rx_freq > 0)
    287 		freq = rx_freq;
    288 	else
    289 		freq = p2p_channel_to_freq(p2p->cfg->reg_class,
    290 					   p2p->cfg->channel);
    291 	if (freq < 0)
    292 		return;
    293 
    294 	if (len < 1 + 2)
    295 		return;
    296 
    297 	dialog_token = *pos++;
    298 	p2p_dbg(p2p, "GAS Initial Request from " MACSTR
    299 		" (dialog token %u, freq %d)",
    300 		MAC2STR(sa), dialog_token, rx_freq);
    301 
    302 	if (*pos != WLAN_EID_ADV_PROTO) {
    303 		p2p_dbg(p2p, "Unexpected IE in GAS Initial Request: %u", *pos);
    304 		return;
    305 	}
    306 	pos++;
    307 
    308 	slen = *pos++;
    309 	next = pos + slen;
    310 	if (next > end || slen < 2) {
    311 		p2p_dbg(p2p, "Invalid IE in GAS Initial Request");
    312 		return;
    313 	}
    314 	pos++; /* skip QueryRespLenLimit and PAME-BI */
    315 
    316 	if (*pos != ACCESS_NETWORK_QUERY_PROTOCOL) {
    317 		p2p_dbg(p2p, "Unsupported GAS advertisement protocol id %u",
    318 			*pos);
    319 		return;
    320 	}
    321 
    322 	pos = next;
    323 	/* Query Request */
    324 	if (pos + 2 > end)
    325 		return;
    326 	slen = WPA_GET_LE16(pos);
    327 	pos += 2;
    328 	if (pos + slen > end)
    329 		return;
    330 	end = pos + slen;
    331 
    332 	/* ANQP Query Request */
    333 	if (pos + 4 > end)
    334 		return;
    335 	if (WPA_GET_LE16(pos) != ANQP_VENDOR_SPECIFIC) {
    336 		p2p_dbg(p2p, "Unsupported ANQP Info ID %u", WPA_GET_LE16(pos));
    337 		return;
    338 	}
    339 	pos += 2;
    340 
    341 	slen = WPA_GET_LE16(pos);
    342 	pos += 2;
    343 	if (pos + slen > end || slen < 3 + 1) {
    344 		p2p_dbg(p2p, "Invalid ANQP Query Request length");
    345 		return;
    346 	}
    347 
    348 	if (WPA_GET_BE24(pos) != OUI_WFA) {
    349 		p2p_dbg(p2p, "Unsupported ANQP OUI %06x", WPA_GET_BE24(pos));
    350 		return;
    351 	}
    352 	pos += 3;
    353 
    354 	if (*pos != P2P_OUI_TYPE) {
    355 		p2p_dbg(p2p, "Unsupported ANQP vendor type %u", *pos);
    356 		return;
    357 	}
    358 	pos++;
    359 
    360 	if (pos + 2 > end)
    361 		return;
    362 	update_indic = WPA_GET_LE16(pos);
    363 	p2p_dbg(p2p, "Service Update Indicator: %u", update_indic);
    364 	pos += 2;
    365 
    366 	p2p->cfg->sd_request(p2p->cfg->cb_ctx, freq, sa, dialog_token,
    367 			     update_indic, pos, end - pos);
    368 	/* the response will be indicated with a call to p2p_sd_response() */
    369 }
    370 
    371 
    372 void p2p_sd_response(struct p2p_data *p2p, int freq, const u8 *dst,
    373 		     u8 dialog_token, const struct wpabuf *resp_tlvs)
    374 {
    375 	struct wpabuf *resp;
    376 
    377 	/* TODO: fix the length limit to match with the maximum frame length */
    378 	if (wpabuf_len(resp_tlvs) > 1400) {
    379 		p2p_dbg(p2p, "SD response long enough to require fragmentation");
    380 		if (p2p->sd_resp) {
    381 			/*
    382 			 * TODO: Could consider storing the fragmented response
    383 			 * separately for each peer to avoid having to drop old
    384 			 * one if there is more than one pending SD query.
    385 			 * Though, that would eat more memory, so there are
    386 			 * also benefits to just using a single buffer.
    387 			 */
    388 			p2p_dbg(p2p, "Drop previous SD response");
    389 			wpabuf_free(p2p->sd_resp);
    390 		}
    391 		p2p->sd_resp = wpabuf_dup(resp_tlvs);
    392 		if (p2p->sd_resp == NULL) {
    393 			p2p_err(p2p, "Failed to allocate SD response fragmentation area");
    394 			return;
    395 		}
    396 		os_memcpy(p2p->sd_resp_addr, dst, ETH_ALEN);
    397 		p2p->sd_resp_dialog_token = dialog_token;
    398 		p2p->sd_resp_pos = 0;
    399 		p2p->sd_frag_id = 0;
    400 		resp = p2p_build_sd_response(dialog_token, WLAN_STATUS_SUCCESS,
    401 					     1, p2p->srv_update_indic, NULL);
    402 	} else {
    403 		p2p_dbg(p2p, "SD response fits in initial response");
    404 		resp = p2p_build_sd_response(dialog_token,
    405 					     WLAN_STATUS_SUCCESS, 0,
    406 					     p2p->srv_update_indic, resp_tlvs);
    407 	}
    408 	if (resp == NULL)
    409 		return;
    410 
    411 	p2p->pending_action_state = P2P_NO_PENDING_ACTION;
    412 	if (p2p_send_action(p2p, freq, dst, p2p->cfg->dev_addr,
    413 			    p2p->cfg->dev_addr,
    414 			    wpabuf_head(resp), wpabuf_len(resp), 200) < 0)
    415 		p2p_dbg(p2p, "Failed to send Action frame");
    416 
    417 	wpabuf_free(resp);
    418 }
    419 
    420 
    421 void p2p_rx_gas_initial_resp(struct p2p_data *p2p, const u8 *sa,
    422 			     const u8 *data, size_t len, int rx_freq)
    423 {
    424 	const u8 *pos = data;
    425 	const u8 *end = data + len;
    426 	const u8 *next;
    427 	u8 dialog_token;
    428 	u16 status_code;
    429 	u16 comeback_delay;
    430 	u16 slen;
    431 	u16 update_indic;
    432 
    433 #ifdef ANDROID_P2P
    434 	if (p2p->state != P2P_SD_DURING_FIND) {
    435 		p2p_dbg(p2p, "P2P: #### Not ignoring unexpected GAS Initial Response from "
    436 			MACSTR " state %d", MAC2STR(sa), p2p->state);
    437 	}
    438 	if (p2p->sd_peer == NULL ||
    439 #else
    440 	if (p2p->state != P2P_SD_DURING_FIND || p2p->sd_peer == NULL ||
    441 #endif
    442 	    os_memcmp(sa, p2p->sd_peer->info.p2p_device_addr, ETH_ALEN) != 0) {
    443 		p2p_dbg(p2p, "Ignore unexpected GAS Initial Response from "
    444 			MACSTR, MAC2STR(sa));
    445 		return;
    446 	}
    447 	p2p->cfg->send_action_done(p2p->cfg->cb_ctx);
    448 	p2p_clear_timeout(p2p);
    449 
    450 	p2p_dbg(p2p, "Received GAS Initial Response from " MACSTR " (len=%d)",
    451 		MAC2STR(sa), (int) len);
    452 
    453 	if (len < 5 + 2) {
    454 		p2p_dbg(p2p, "Too short GAS Initial Response frame");
    455 		return;
    456 	}
    457 
    458 	dialog_token = *pos++;
    459 	/* TODO: check dialog_token match */
    460 	status_code = WPA_GET_LE16(pos);
    461 	pos += 2;
    462 	comeback_delay = WPA_GET_LE16(pos);
    463 	pos += 2;
    464 	p2p_dbg(p2p, "dialog_token=%u status_code=%u comeback_delay=%u",
    465 		dialog_token, status_code, comeback_delay);
    466 	if (status_code) {
    467 		p2p_dbg(p2p, "Service Discovery failed: status code %u",
    468 			status_code);
    469 		return;
    470 	}
    471 
    472 	if (*pos != WLAN_EID_ADV_PROTO) {
    473 		p2p_dbg(p2p, "Unexpected IE in GAS Initial Response: %u", *pos);
    474 		return;
    475 	}
    476 	pos++;
    477 
    478 	slen = *pos++;
    479 	next = pos + slen;
    480 	if (next > end || slen < 2) {
    481 		p2p_dbg(p2p, "Invalid IE in GAS Initial Response");
    482 		return;
    483 	}
    484 	pos++; /* skip QueryRespLenLimit and PAME-BI */
    485 
    486 	if (*pos != ACCESS_NETWORK_QUERY_PROTOCOL) {
    487 		p2p_dbg(p2p, "Unsupported GAS advertisement protocol id %u",
    488 			*pos);
    489 		return;
    490 	}
    491 
    492 	pos = next;
    493 	/* Query Response */
    494 	if (pos + 2 > end) {
    495 		p2p_dbg(p2p, "Too short Query Response");
    496 		return;
    497 	}
    498 	slen = WPA_GET_LE16(pos);
    499 	pos += 2;
    500 	p2p_dbg(p2p, "Query Response Length: %d", slen);
    501 	if (pos + slen > end) {
    502 		p2p_dbg(p2p, "Not enough Query Response data");
    503 		return;
    504 	}
    505 	end = pos + slen;
    506 
    507 	if (comeback_delay) {
    508 		p2p_dbg(p2p, "Fragmented response - request fragments");
    509 		if (p2p->sd_rx_resp) {
    510 			p2p_dbg(p2p, "Drop old SD reassembly buffer");
    511 			wpabuf_free(p2p->sd_rx_resp);
    512 			p2p->sd_rx_resp = NULL;
    513 		}
    514 		p2p_send_gas_comeback_req(p2p, sa, dialog_token, rx_freq);
    515 		return;
    516 	}
    517 
    518 	/* ANQP Query Response */
    519 	if (pos + 4 > end)
    520 		return;
    521 	if (WPA_GET_LE16(pos) != ANQP_VENDOR_SPECIFIC) {
    522 		p2p_dbg(p2p, "Unsupported ANQP Info ID %u", WPA_GET_LE16(pos));
    523 		return;
    524 	}
    525 	pos += 2;
    526 
    527 	slen = WPA_GET_LE16(pos);
    528 	pos += 2;
    529 	if (pos + slen > end || slen < 3 + 1) {
    530 		p2p_dbg(p2p, "Invalid ANQP Query Response length");
    531 		return;
    532 	}
    533 
    534 	if (WPA_GET_BE24(pos) != OUI_WFA) {
    535 		p2p_dbg(p2p, "Unsupported ANQP OUI %06x", WPA_GET_BE24(pos));
    536 		return;
    537 	}
    538 	pos += 3;
    539 
    540 	if (*pos != P2P_OUI_TYPE) {
    541 		p2p_dbg(p2p, "Unsupported ANQP vendor type %u", *pos);
    542 		return;
    543 	}
    544 	pos++;
    545 
    546 	if (pos + 2 > end)
    547 		return;
    548 	update_indic = WPA_GET_LE16(pos);
    549 	p2p_dbg(p2p, "Service Update Indicator: %u", update_indic);
    550 	pos += 2;
    551 
    552 	p2p->sd_peer->flags |= P2P_DEV_SD_INFO;
    553 	p2p->sd_peer->flags &= ~P2P_DEV_SD_SCHEDULE;
    554 	p2p->sd_peer = NULL;
    555 
    556 	if (p2p->sd_query) {
    557 		if (!p2p->sd_query->for_all_peers) {
    558 			struct p2p_sd_query *q;
    559 			p2p_dbg(p2p, "Remove completed SD query %p",
    560 				p2p->sd_query);
    561 			q = p2p->sd_query;
    562 			p2p_unlink_sd_query(p2p, p2p->sd_query);
    563 			p2p_free_sd_query(q);
    564 		}
    565 		p2p->sd_query = NULL;
    566 	}
    567 
    568 	if (p2p->cfg->sd_response)
    569 		p2p->cfg->sd_response(p2p->cfg->cb_ctx, sa, update_indic,
    570 				      pos, end - pos);
    571 	p2p_continue_find(p2p);
    572 }
    573 
    574 
    575 void p2p_rx_gas_comeback_req(struct p2p_data *p2p, const u8 *sa,
    576 			     const u8 *data, size_t len, int rx_freq)
    577 {
    578 	struct wpabuf *resp;
    579 	u8 dialog_token;
    580 	size_t frag_len;
    581 	int more = 0;
    582 
    583 	wpa_hexdump(MSG_DEBUG, "P2P: RX GAS Comeback Request", data, len);
    584 	if (len < 1)
    585 		return;
    586 	dialog_token = *data;
    587 	p2p_dbg(p2p, "Dialog Token: %u", dialog_token);
    588 	if (dialog_token != p2p->sd_resp_dialog_token) {
    589 		p2p_dbg(p2p, "No pending SD response fragment for dialog token %u",
    590 			dialog_token);
    591 		return;
    592 	}
    593 
    594 	if (p2p->sd_resp == NULL) {
    595 		p2p_dbg(p2p, "No pending SD response fragment available");
    596 		return;
    597 	}
    598 	if (os_memcmp(sa, p2p->sd_resp_addr, ETH_ALEN) != 0) {
    599 		p2p_dbg(p2p, "No pending SD response fragment for " MACSTR,
    600 			MAC2STR(sa));
    601 		return;
    602 	}
    603 
    604 	frag_len = wpabuf_len(p2p->sd_resp) - p2p->sd_resp_pos;
    605 	if (frag_len > 1400) {
    606 		frag_len = 1400;
    607 		more = 1;
    608 	}
    609 	resp = p2p_build_gas_comeback_resp(dialog_token, WLAN_STATUS_SUCCESS,
    610 					   p2p->srv_update_indic,
    611 					   wpabuf_head_u8(p2p->sd_resp) +
    612 					   p2p->sd_resp_pos, frag_len,
    613 					   p2p->sd_frag_id, more,
    614 					   wpabuf_len(p2p->sd_resp));
    615 	if (resp == NULL)
    616 		return;
    617 	p2p_dbg(p2p, "Send GAS Comeback Response (frag_id %d more=%d frag_len=%d)",
    618 		p2p->sd_frag_id, more, (int) frag_len);
    619 	p2p->sd_frag_id++;
    620 	p2p->sd_resp_pos += frag_len;
    621 
    622 	if (more) {
    623 		p2p_dbg(p2p, "%d more bytes remain to be sent",
    624 			(int) (wpabuf_len(p2p->sd_resp) - p2p->sd_resp_pos));
    625 	} else {
    626 		p2p_dbg(p2p, "All fragments of SD response sent");
    627 		wpabuf_free(p2p->sd_resp);
    628 		p2p->sd_resp = NULL;
    629 	}
    630 
    631 	p2p->pending_action_state = P2P_NO_PENDING_ACTION;
    632 	if (p2p_send_action(p2p, rx_freq, sa, p2p->cfg->dev_addr,
    633 			    p2p->cfg->dev_addr,
    634 			    wpabuf_head(resp), wpabuf_len(resp), 200) < 0)
    635 		p2p_dbg(p2p, "Failed to send Action frame");
    636 
    637 	wpabuf_free(resp);
    638 }
    639 
    640 
    641 void p2p_rx_gas_comeback_resp(struct p2p_data *p2p, const u8 *sa,
    642 			      const u8 *data, size_t len, int rx_freq)
    643 {
    644 	const u8 *pos = data;
    645 	const u8 *end = data + len;
    646 	const u8 *next;
    647 	u8 dialog_token;
    648 	u16 status_code;
    649 	u8 frag_id;
    650 	u8 more_frags;
    651 	u16 comeback_delay;
    652 	u16 slen;
    653 
    654 	wpa_hexdump(MSG_DEBUG, "P2P: RX GAS Comeback Response", data, len);
    655 
    656 #ifdef ANDROID_P2P
    657 	if (p2p->state != P2P_SD_DURING_FIND) {
    658 		p2p_dbg(p2p, "P2P: #### Not ignoring unexpected GAS Comeback Response from "
    659 			MACSTR " state %d", MAC2STR(sa), p2p->state);
    660 	}
    661 	if (p2p->sd_peer == NULL ||
    662 #else
    663 	if (p2p->state != P2P_SD_DURING_FIND || p2p->sd_peer == NULL ||
    664 #endif
    665 	    os_memcmp(sa, p2p->sd_peer->info.p2p_device_addr, ETH_ALEN) != 0) {
    666 		p2p_dbg(p2p, "Ignore unexpected GAS Comeback Response from "
    667 			MACSTR, MAC2STR(sa));
    668 		return;
    669 	}
    670 	p2p->cfg->send_action_done(p2p->cfg->cb_ctx);
    671 	p2p_clear_timeout(p2p);
    672 
    673 	p2p_dbg(p2p, "Received GAS Comeback Response from " MACSTR " (len=%d)",
    674 		MAC2STR(sa), (int) len);
    675 
    676 	if (len < 6 + 2) {
    677 		p2p_dbg(p2p, "Too short GAS Comeback Response frame");
    678 		return;
    679 	}
    680 
    681 	dialog_token = *pos++;
    682 	/* TODO: check dialog_token match */
    683 	status_code = WPA_GET_LE16(pos);
    684 	pos += 2;
    685 	frag_id = *pos & 0x7f;
    686 	more_frags = (*pos & 0x80) >> 7;
    687 	pos++;
    688 	comeback_delay = WPA_GET_LE16(pos);
    689 	pos += 2;
    690 	p2p_dbg(p2p, "dialog_token=%u status_code=%u frag_id=%d more_frags=%d "
    691 		"comeback_delay=%u",
    692 		dialog_token, status_code, frag_id, more_frags,
    693 		comeback_delay);
    694 	/* TODO: check frag_id match */
    695 	if (status_code) {
    696 		p2p_dbg(p2p, "Service Discovery failed: status code %u",
    697 			status_code);
    698 		return;
    699 	}
    700 
    701 	if (*pos != WLAN_EID_ADV_PROTO) {
    702 		p2p_dbg(p2p, "Unexpected IE in GAS Comeback Response: %u",
    703 			*pos);
    704 		return;
    705 	}
    706 	pos++;
    707 
    708 	slen = *pos++;
    709 	next = pos + slen;
    710 	if (next > end || slen < 2) {
    711 		p2p_dbg(p2p, "Invalid IE in GAS Comeback Response");
    712 		return;
    713 	}
    714 	pos++; /* skip QueryRespLenLimit and PAME-BI */
    715 
    716 	if (*pos != ACCESS_NETWORK_QUERY_PROTOCOL) {
    717 		p2p_dbg(p2p, "Unsupported GAS advertisement protocol id %u",
    718 			*pos);
    719 		return;
    720 	}
    721 
    722 	pos = next;
    723 	/* Query Response */
    724 	if (pos + 2 > end) {
    725 		p2p_dbg(p2p, "Too short Query Response");
    726 		return;
    727 	}
    728 	slen = WPA_GET_LE16(pos);
    729 	pos += 2;
    730 	p2p_dbg(p2p, "Query Response Length: %d", slen);
    731 	if (pos + slen > end) {
    732 		p2p_dbg(p2p, "Not enough Query Response data");
    733 		return;
    734 	}
    735 	if (slen == 0) {
    736 		p2p_dbg(p2p, "No Query Response data");
    737 		return;
    738 	}
    739 	end = pos + slen;
    740 
    741 	if (p2p->sd_rx_resp) {
    742 		 /*
    743 		  * ANQP header is only included in the first fragment; rest of
    744 		  * the fragments start with continue TLVs.
    745 		  */
    746 		goto skip_nqp_header;
    747 	}
    748 
    749 	/* ANQP Query Response */
    750 	if (pos + 4 > end)
    751 		return;
    752 	if (WPA_GET_LE16(pos) != ANQP_VENDOR_SPECIFIC) {
    753 		p2p_dbg(p2p, "Unsupported ANQP Info ID %u", WPA_GET_LE16(pos));
    754 		return;
    755 	}
    756 	pos += 2;
    757 
    758 	slen = WPA_GET_LE16(pos);
    759 	pos += 2;
    760 	p2p_dbg(p2p, "ANQP Query Response length: %u", slen);
    761 	if (slen < 3 + 1) {
    762 		p2p_dbg(p2p, "Invalid ANQP Query Response length");
    763 		return;
    764 	}
    765 	if (pos + 4 > end)
    766 		return;
    767 
    768 	if (WPA_GET_BE24(pos) != OUI_WFA) {
    769 		p2p_dbg(p2p, "Unsupported ANQP OUI %06x", WPA_GET_BE24(pos));
    770 		return;
    771 	}
    772 	pos += 3;
    773 
    774 	if (*pos != P2P_OUI_TYPE) {
    775 		p2p_dbg(p2p, "Unsupported ANQP vendor type %u", *pos);
    776 		return;
    777 	}
    778 	pos++;
    779 
    780 	if (pos + 2 > end)
    781 		return;
    782 	p2p->sd_rx_update_indic = WPA_GET_LE16(pos);
    783 	p2p_dbg(p2p, "Service Update Indicator: %u", p2p->sd_rx_update_indic);
    784 	pos += 2;
    785 
    786 skip_nqp_header:
    787 	if (wpabuf_resize(&p2p->sd_rx_resp, end - pos) < 0)
    788 		return;
    789 	wpabuf_put_data(p2p->sd_rx_resp, pos, end - pos);
    790 	p2p_dbg(p2p, "Current SD reassembly buffer length: %u",
    791 		(unsigned int) wpabuf_len(p2p->sd_rx_resp));
    792 
    793 	if (more_frags) {
    794 		p2p_dbg(p2p, "More fragments remains");
    795 		/* TODO: what would be a good size limit? */
    796 		if (wpabuf_len(p2p->sd_rx_resp) > 64000) {
    797 			wpabuf_free(p2p->sd_rx_resp);
    798 			p2p->sd_rx_resp = NULL;
    799 			p2p_dbg(p2p, "Too long SD response - drop it");
    800 			return;
    801 		}
    802 		p2p_send_gas_comeback_req(p2p, sa, dialog_token, rx_freq);
    803 		return;
    804 	}
    805 
    806 	p2p->sd_peer->flags |= P2P_DEV_SD_INFO;
    807 	p2p->sd_peer->flags &= ~P2P_DEV_SD_SCHEDULE;
    808 	p2p->sd_peer = NULL;
    809 
    810 	if (p2p->sd_query) {
    811 		if (!p2p->sd_query->for_all_peers) {
    812 			struct p2p_sd_query *q;
    813 			p2p_dbg(p2p, "Remove completed SD query %p",
    814 				p2p->sd_query);
    815 			q = p2p->sd_query;
    816 			p2p_unlink_sd_query(p2p, p2p->sd_query);
    817 			p2p_free_sd_query(q);
    818 		}
    819 		p2p->sd_query = NULL;
    820 	}
    821 
    822 	if (p2p->cfg->sd_response)
    823 		p2p->cfg->sd_response(p2p->cfg->cb_ctx, sa,
    824 				      p2p->sd_rx_update_indic,
    825 				      wpabuf_head(p2p->sd_rx_resp),
    826 				      wpabuf_len(p2p->sd_rx_resp));
    827 	wpabuf_free(p2p->sd_rx_resp);
    828 	p2p->sd_rx_resp = NULL;
    829 
    830 	p2p_continue_find(p2p);
    831 }
    832 
    833 
    834 void * p2p_sd_request(struct p2p_data *p2p, const u8 *dst,
    835 		      const struct wpabuf *tlvs)
    836 {
    837 	struct p2p_sd_query *q;
    838 #ifdef ANDROID_P2P
    839 	/* Currently, supplicant doesn't support more than one pending broadcast SD request.
    840 	 * So reject if application is registering another one before cancelling the existing one.
    841 	 */
    842 	for (q = p2p->sd_queries; q; q = q->next) {
    843 		if( (q->for_all_peers == 1) && (!dst)) {
    844 				wpa_printf(MSG_ERROR, "P2P: Already one pending"
    845 					" Broadcast request. Please cancel the current one"
    846 					" before adding a new one");
    847 				return NULL;
    848 		}
    849 	}
    850 #endif
    851 
    852 	q = os_zalloc(sizeof(*q));
    853 	if (q == NULL)
    854 		return NULL;
    855 
    856 	if (dst)
    857 		os_memcpy(q->peer, dst, ETH_ALEN);
    858 	else
    859 		q->for_all_peers = 1;
    860 
    861 	q->tlvs = wpabuf_dup(tlvs);
    862 	if (q->tlvs == NULL) {
    863 		p2p_free_sd_query(q);
    864 		return NULL;
    865 	}
    866 
    867 	q->next = p2p->sd_queries;
    868 	p2p->sd_queries = q;
    869 	p2p_dbg(p2p, "Added SD Query %p", q);
    870 
    871 	if (dst == NULL) {
    872 		struct p2p_device *dev;
    873 		dl_list_for_each(dev, &p2p->devices, struct p2p_device, list)
    874 			dev->flags &= ~P2P_DEV_SD_INFO;
    875 	}
    876 
    877 	return q;
    878 }
    879 
    880 
    881 #ifdef CONFIG_WIFI_DISPLAY
    882 void * p2p_sd_request_wfd(struct p2p_data *p2p, const u8 *dst,
    883 			  const struct wpabuf *tlvs)
    884 {
    885 	struct p2p_sd_query *q;
    886 	q = p2p_sd_request(p2p, dst, tlvs);
    887 	if (q)
    888 		q->wsd = 1;
    889 	return q;
    890 }
    891 #endif /* CONFIG_WIFI_DISPLAY */
    892 
    893 
    894 void p2p_sd_service_update(struct p2p_data *p2p)
    895 {
    896 	p2p->srv_update_indic++;
    897 }
    898 
    899 
    900 int p2p_sd_cancel_request(struct p2p_data *p2p, void *req)
    901 {
    902 	if (p2p_unlink_sd_query(p2p, req)) {
    903 		p2p_dbg(p2p, "Cancel pending SD query %p", req);
    904 #ifdef ANDROID_P2P
    905 		p2p->sd_dev_list = NULL;
    906 #endif
    907 		p2p_free_sd_query(req);
    908 		return 0;
    909 	}
    910 	return -1;
    911 }
    912