xref: /dragonfly/contrib/wpa_supplicant/src/p2p/p2p_sd.c (revision 3a84a4273475ed07d0ab1c2dfeffdfedef35d9cd)
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
wfd_wsd_supported(struct wpabuf * wfd)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 
p2p_pending_sd_req(struct p2p_data * p2p,struct p2p_device * dev)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                         os_memcmp(q->peer, dev->info.p2p_device_addr, ETH_ALEN) ==
83                         0)
84                               goto found;
85           }
86 
87           return NULL;
88 
89 found:
90           if (dev->sd_reqs > 100) {
91                     p2p_dbg(p2p, "Too many SD request attempts to " MACSTR
92                               " - skip remaining queries",
93                               MAC2STR(dev->info.p2p_device_addr));
94                     return NULL;
95           }
96           return q;
97 }
98 
99 
p2p_decrease_sd_bc_queries(struct p2p_data * p2p,int query_number)100 static void p2p_decrease_sd_bc_queries(struct p2p_data *p2p, int query_number)
101 {
102           struct p2p_device *dev;
103 
104           p2p->num_p2p_sd_queries--;
105           dl_list_for_each(dev, &p2p->devices, struct p2p_device, list) {
106                     if (query_number <= dev->sd_pending_bcast_queries - 1) {
107                               /*
108                                * Query not yet sent to the device and it is to be
109                                * removed, so update the pending count.
110                               */
111                               dev->sd_pending_bcast_queries--;
112                     }
113           }
114 }
115 
116 
p2p_unlink_sd_query(struct p2p_data * p2p,struct p2p_sd_query * query)117 static int p2p_unlink_sd_query(struct p2p_data *p2p,
118                                      struct p2p_sd_query *query)
119 {
120           struct p2p_sd_query *q, *prev;
121           int query_number = 0;
122 
123           q = p2p->sd_queries;
124           prev = NULL;
125           while (q) {
126                     if (q == query) {
127                               /* If the query is a broadcast query, decrease one from
128                                * all the devices */
129                               if (query->for_all_peers)
130                                         p2p_decrease_sd_bc_queries(p2p, query_number);
131                               if (prev)
132                                         prev->next = q->next;
133                               else
134                                         p2p->sd_queries = q->next;
135                               if (p2p->sd_query == query)
136                                         p2p->sd_query = NULL;
137                               return 1;
138                     }
139                     if (q->for_all_peers)
140                               query_number++;
141                     prev = q;
142                     q = q->next;
143           }
144           return 0;
145 }
146 
147 
p2p_free_sd_query(struct p2p_sd_query * q)148 static void p2p_free_sd_query(struct p2p_sd_query *q)
149 {
150           if (q == NULL)
151                     return;
152           wpabuf_free(q->tlvs);
153           os_free(q);
154 }
155 
156 
p2p_free_sd_queries(struct p2p_data * p2p)157 void p2p_free_sd_queries(struct p2p_data *p2p)
158 {
159           struct p2p_sd_query *q, *prev;
160           q = p2p->sd_queries;
161           p2p->sd_queries = NULL;
162           while (q) {
163                     prev = q;
164                     q = q->next;
165                     p2p_free_sd_query(prev);
166           }
167           p2p->num_p2p_sd_queries = 0;
168 }
169 
170 
p2p_build_sd_query(u16 update_indic,struct wpabuf * tlvs)171 static struct wpabuf * p2p_build_sd_query(u16 update_indic,
172                                                     struct wpabuf *tlvs)
173 {
174           struct wpabuf *buf;
175           u8 *len_pos;
176 
177           buf = gas_anqp_build_initial_req(0, 100 + wpabuf_len(tlvs));
178           if (buf == NULL)
179                     return NULL;
180 
181           /* ANQP Query Request Frame */
182           len_pos = gas_anqp_add_element(buf, ANQP_VENDOR_SPECIFIC);
183           wpabuf_put_be32(buf, P2P_IE_VENDOR_TYPE);
184           wpabuf_put_le16(buf, update_indic); /* Service Update Indicator */
185           wpabuf_put_buf(buf, tlvs);
186           gas_anqp_set_element_len(buf, len_pos);
187 
188           gas_anqp_set_len(buf);
189 
190           return buf;
191 }
192 
193 
p2p_send_gas_comeback_req(struct p2p_data * p2p,const u8 * dst,u8 dialog_token,int freq)194 static void p2p_send_gas_comeback_req(struct p2p_data *p2p, const u8 *dst,
195                                               u8 dialog_token, int freq)
196 {
197           struct wpabuf *req;
198 
199           req = gas_build_comeback_req(dialog_token);
200           if (req == NULL)
201                     return;
202 
203           p2p->pending_action_state = P2P_NO_PENDING_ACTION;
204           if (p2p_send_action(p2p, freq, dst, p2p->cfg->dev_addr, dst,
205                                   wpabuf_head(req), wpabuf_len(req), 200) < 0)
206                     p2p_dbg(p2p, "Failed to send Action frame");
207 
208           wpabuf_free(req);
209 }
210 
211 
p2p_build_sd_response(u8 dialog_token,u16 status_code,u16 comeback_delay,u16 update_indic,const struct wpabuf * tlvs)212 static struct wpabuf * p2p_build_sd_response(u8 dialog_token, u16 status_code,
213                                                        u16 comeback_delay,
214                                                        u16 update_indic,
215                                                        const struct wpabuf *tlvs)
216 {
217           struct wpabuf *buf;
218           u8 *len_pos;
219 
220           buf = gas_anqp_build_initial_resp(dialog_token, status_code,
221                                                     comeback_delay,
222                                                     100 + (tlvs ? wpabuf_len(tlvs) : 0));
223           if (buf == NULL)
224                     return NULL;
225 
226           if (tlvs) {
227                     /* ANQP Query Response Frame */
228                     len_pos = gas_anqp_add_element(buf, ANQP_VENDOR_SPECIFIC);
229                     wpabuf_put_be32(buf, P2P_IE_VENDOR_TYPE);
230                      /* Service Update Indicator */
231                     wpabuf_put_le16(buf, update_indic);
232                     wpabuf_put_buf(buf, tlvs);
233                     gas_anqp_set_element_len(buf, len_pos);
234           }
235 
236           gas_anqp_set_len(buf);
237 
238           return buf;
239 }
240 
241 
p2p_build_gas_comeback_resp(u8 dialog_token,u16 status_code,u16 update_indic,const u8 * data,size_t len,u8 frag_id,u8 more,u16 total_len)242 static struct wpabuf * p2p_build_gas_comeback_resp(u8 dialog_token,
243                                                                u16 status_code,
244                                                                u16 update_indic,
245                                                                const u8 *data, size_t len,
246                                                                u8 frag_id, u8 more,
247                                                                u16 total_len)
248 {
249           struct wpabuf *buf;
250 
251           buf = gas_anqp_build_comeback_resp(dialog_token, status_code, frag_id,
252                                                      more, 0, 100 + len);
253           if (buf == NULL)
254                     return NULL;
255 
256           if (frag_id == 0) {
257                     /* ANQP Query Response Frame */
258                     wpabuf_put_le16(buf, ANQP_VENDOR_SPECIFIC); /* Info ID */
259                     wpabuf_put_le16(buf, 3 + 1 + 2 + total_len);
260                     wpabuf_put_be32(buf, P2P_IE_VENDOR_TYPE);
261                     /* Service Update Indicator */
262                     wpabuf_put_le16(buf, update_indic);
263           }
264 
265           wpabuf_put_data(buf, data, len);
266           gas_anqp_set_len(buf);
267 
268           return buf;
269 }
270 
271 
p2p_start_sd(struct p2p_data * p2p,struct p2p_device * dev)272 int p2p_start_sd(struct p2p_data *p2p, struct p2p_device *dev)
273 {
274           struct wpabuf *req;
275           int ret = 0;
276           struct p2p_sd_query *query;
277           int freq;
278           unsigned int wait_time;
279 
280           freq = dev->listen_freq > 0 ? dev->listen_freq : dev->oper_freq;
281           if (freq <= 0) {
282                     p2p_dbg(p2p, "No Listen/Operating frequency known for the peer "
283                               MACSTR " to send SD Request",
284                               MAC2STR(dev->info.p2p_device_addr));
285                     return -1;
286           }
287 
288           query = p2p_pending_sd_req(p2p, dev);
289           if (query == NULL)
290                     return -1;
291           if (p2p->state == P2P_SEARCH &&
292               os_memcmp(p2p->sd_query_no_ack, dev->info.p2p_device_addr,
293                           ETH_ALEN) == 0) {
294                     p2p_dbg(p2p, "Do not start Service Discovery with " MACSTR
295                               " due to it being the first no-ACK peer in this search iteration",
296                               MAC2STR(dev->info.p2p_device_addr));
297                     return -2;
298           }
299 
300           p2p_dbg(p2p, "Start Service Discovery with " MACSTR,
301                     MAC2STR(dev->info.p2p_device_addr));
302 
303           req = p2p_build_sd_query(p2p->srv_update_indic, query->tlvs);
304           if (req == NULL)
305                     return -1;
306 
307           dev->sd_reqs++;
308           p2p->sd_peer = dev;
309           p2p->sd_query = query;
310           p2p->pending_action_state = P2P_PENDING_SD;
311 
312           wait_time = 5000;
313           if (p2p->cfg->max_listen && wait_time > p2p->cfg->max_listen)
314                     wait_time = p2p->cfg->max_listen;
315           if (p2p_send_action(p2p, freq, dev->info.p2p_device_addr,
316                                   p2p->cfg->dev_addr, dev->info.p2p_device_addr,
317                                   wpabuf_head(req), wpabuf_len(req), wait_time) < 0) {
318                     p2p_dbg(p2p, "Failed to send Action frame");
319                     ret = -1;
320           }
321 
322           wpabuf_free(req);
323 
324           return ret;
325 }
326 
327 
p2p_rx_gas_initial_req(struct p2p_data * p2p,const u8 * sa,const u8 * data,size_t len,int rx_freq)328 void p2p_rx_gas_initial_req(struct p2p_data *p2p, const u8 *sa,
329                                   const u8 *data, size_t len, int rx_freq)
330 {
331           const u8 *pos = data;
332           const u8 *end = data + len;
333           const u8 *next;
334           u8 dialog_token;
335           u16 slen;
336           int freq;
337           u16 update_indic;
338 
339 
340           if (p2p->cfg->sd_request == NULL)
341                     return;
342 
343           if (rx_freq > 0)
344                     freq = rx_freq;
345           else
346                     freq = p2p_channel_to_freq(p2p->cfg->reg_class,
347                                                      p2p->cfg->channel);
348           if (freq < 0)
349                     return;
350 
351           if (len < 1 + 2)
352                     return;
353 
354           dialog_token = *pos++;
355           p2p_dbg(p2p, "GAS Initial Request from " MACSTR
356                     " (dialog token %u, freq %d)",
357                     MAC2STR(sa), dialog_token, rx_freq);
358 
359           if (*pos != WLAN_EID_ADV_PROTO) {
360                     p2p_dbg(p2p, "Unexpected IE in GAS Initial Request: %u", *pos);
361                     return;
362           }
363           pos++;
364 
365           slen = *pos++;
366           if (slen > end - pos || slen < 2) {
367                     p2p_dbg(p2p, "Invalid IE in GAS Initial Request");
368                     return;
369           }
370           next = pos + slen;
371           pos++; /* skip QueryRespLenLimit and PAME-BI */
372 
373           if (*pos != ACCESS_NETWORK_QUERY_PROTOCOL) {
374                     p2p_dbg(p2p, "Unsupported GAS advertisement protocol id %u",
375                               *pos);
376                     return;
377           }
378 
379           pos = next;
380           /* Query Request */
381           if (end - pos < 2)
382                     return;
383           slen = WPA_GET_LE16(pos);
384           pos += 2;
385           if (slen > end - pos)
386                     return;
387           end = pos + slen;
388 
389           /* ANQP Query Request */
390           if (end - pos < 4)
391                     return;
392           if (WPA_GET_LE16(pos) != ANQP_VENDOR_SPECIFIC) {
393                     p2p_dbg(p2p, "Unsupported ANQP Info ID %u", WPA_GET_LE16(pos));
394                     return;
395           }
396           pos += 2;
397 
398           slen = WPA_GET_LE16(pos);
399           pos += 2;
400           if (slen > end - pos || slen < 3 + 1) {
401                     p2p_dbg(p2p, "Invalid ANQP Query Request length");
402                     return;
403           }
404 
405           if (WPA_GET_BE32(pos) != P2P_IE_VENDOR_TYPE) {
406                     p2p_dbg(p2p, "Unsupported ANQP vendor OUI-type %08x",
407                               WPA_GET_BE32(pos));
408                     return;
409           }
410           pos += 4;
411 
412           if (end - pos < 2)
413                     return;
414           update_indic = WPA_GET_LE16(pos);
415           p2p_dbg(p2p, "Service Update Indicator: %u", update_indic);
416           pos += 2;
417 
418           p2p->cfg->sd_request(p2p->cfg->cb_ctx, freq, sa, dialog_token,
419                                    update_indic, pos, end - pos);
420           /* the response will be indicated with a call to p2p_sd_response() */
421 }
422 
423 
p2p_sd_response(struct p2p_data * p2p,int freq,const u8 * dst,u8 dialog_token,const struct wpabuf * resp_tlvs)424 void p2p_sd_response(struct p2p_data *p2p, int freq, const u8 *dst,
425                          u8 dialog_token, const struct wpabuf *resp_tlvs)
426 {
427           struct wpabuf *resp;
428           size_t max_len;
429           unsigned int wait_time = 200;
430 
431           /*
432            * In the 60 GHz, we have a smaller maximum frame length for management
433            * frames.
434            */
435           max_len = (freq > 56160) ? 928 : 1400;
436 
437           /* TODO: fix the length limit to match with the maximum frame length */
438           if (wpabuf_len(resp_tlvs) > max_len) {
439                     p2p_dbg(p2p, "SD response long enough to require fragmentation");
440                     if (p2p->sd_resp) {
441                               /*
442                                * TODO: Could consider storing the fragmented response
443                                * separately for each peer to avoid having to drop old
444                                * one if there is more than one pending SD query.
445                                * Though, that would eat more memory, so there are
446                                * also benefits to just using a single buffer.
447                                */
448                               p2p_dbg(p2p, "Drop previous SD response");
449                               wpabuf_free(p2p->sd_resp);
450                     }
451                     p2p->sd_resp = wpabuf_dup(resp_tlvs);
452                     if (p2p->sd_resp == NULL) {
453                               p2p_err(p2p, "Failed to allocate SD response fragmentation area");
454                               return;
455                     }
456                     os_memcpy(p2p->sd_resp_addr, dst, ETH_ALEN);
457                     p2p->sd_resp_dialog_token = dialog_token;
458                     p2p->sd_resp_pos = 0;
459                     p2p->sd_frag_id = 0;
460                     resp = p2p_build_sd_response(dialog_token, WLAN_STATUS_SUCCESS,
461                                                        1, p2p->srv_update_indic, NULL);
462           } else {
463                     p2p_dbg(p2p, "SD response fits in initial response");
464                     wait_time = 0; /* no more SD frames in the sequence */
465                     resp = p2p_build_sd_response(dialog_token,
466                                                        WLAN_STATUS_SUCCESS, 0,
467                                                        p2p->srv_update_indic, resp_tlvs);
468           }
469           if (resp == NULL)
470                     return;
471 
472           p2p->pending_action_state = P2P_NO_PENDING_ACTION;
473           if (p2p_send_action(p2p, freq, dst, p2p->cfg->dev_addr,
474                                   p2p->cfg->dev_addr,
475                                   wpabuf_head(resp), wpabuf_len(resp), wait_time) < 0)
476                     p2p_dbg(p2p, "Failed to send Action frame");
477 
478           wpabuf_free(resp);
479 }
480 
481 
p2p_rx_gas_initial_resp(struct p2p_data * p2p,const u8 * sa,const u8 * data,size_t len,int rx_freq)482 void p2p_rx_gas_initial_resp(struct p2p_data *p2p, const u8 *sa,
483                                    const u8 *data, size_t len, int rx_freq)
484 {
485           const u8 *pos = data;
486           const u8 *end = data + len;
487           const u8 *next;
488           u8 dialog_token;
489           u16 status_code;
490           u16 comeback_delay;
491           u16 slen;
492           u16 update_indic;
493 
494           if (p2p->state != P2P_SD_DURING_FIND || p2p->sd_peer == NULL ||
495               os_memcmp(sa, p2p->sd_peer->info.p2p_device_addr, ETH_ALEN) != 0) {
496                     p2p_dbg(p2p, "Ignore unexpected GAS Initial Response from "
497                               MACSTR, MAC2STR(sa));
498                     return;
499           }
500           p2p->cfg->send_action_done(p2p->cfg->cb_ctx);
501           p2p_clear_timeout(p2p);
502 
503           p2p_dbg(p2p, "Received GAS Initial Response from " MACSTR " (len=%d)",
504                     MAC2STR(sa), (int) len);
505 
506           if (len < 5 + 2) {
507                     p2p_dbg(p2p, "Too short GAS Initial Response frame");
508                     return;
509           }
510 
511           dialog_token = *pos++;
512           /* TODO: check dialog_token match */
513           status_code = WPA_GET_LE16(pos);
514           pos += 2;
515           comeback_delay = WPA_GET_LE16(pos);
516           pos += 2;
517           p2p_dbg(p2p, "dialog_token=%u status_code=%u comeback_delay=%u",
518                     dialog_token, status_code, comeback_delay);
519           if (status_code) {
520                     p2p_dbg(p2p, "Service Discovery failed: status code %u",
521                               status_code);
522                     return;
523           }
524 
525           if (*pos != WLAN_EID_ADV_PROTO) {
526                     p2p_dbg(p2p, "Unexpected IE in GAS Initial Response: %u", *pos);
527                     return;
528           }
529           pos++;
530 
531           slen = *pos++;
532           if (slen > end - pos || slen < 2) {
533                     p2p_dbg(p2p, "Invalid IE in GAS Initial Response");
534                     return;
535           }
536           next = pos + slen;
537           pos++; /* skip QueryRespLenLimit and PAME-BI */
538 
539           if (*pos != ACCESS_NETWORK_QUERY_PROTOCOL) {
540                     p2p_dbg(p2p, "Unsupported GAS advertisement protocol id %u",
541                               *pos);
542                     return;
543           }
544 
545           pos = next;
546           /* Query Response */
547           if (end - pos < 2) {
548                     p2p_dbg(p2p, "Too short Query Response");
549                     return;
550           }
551           slen = WPA_GET_LE16(pos);
552           pos += 2;
553           p2p_dbg(p2p, "Query Response Length: %d", slen);
554           if (slen > end - pos) {
555                     p2p_dbg(p2p, "Not enough Query Response data");
556                     return;
557           }
558           end = pos + slen;
559 
560           if (comeback_delay) {
561                     p2p_dbg(p2p, "Fragmented response - request fragments");
562                     if (p2p->sd_rx_resp) {
563                               p2p_dbg(p2p, "Drop old SD reassembly buffer");
564                               wpabuf_free(p2p->sd_rx_resp);
565                               p2p->sd_rx_resp = NULL;
566                     }
567                     p2p_send_gas_comeback_req(p2p, sa, dialog_token, rx_freq);
568                     return;
569           }
570 
571           /* ANQP Query Response */
572           if (end - pos < 4)
573                     return;
574           if (WPA_GET_LE16(pos) != ANQP_VENDOR_SPECIFIC) {
575                     p2p_dbg(p2p, "Unsupported ANQP Info ID %u", WPA_GET_LE16(pos));
576                     return;
577           }
578           pos += 2;
579 
580           slen = WPA_GET_LE16(pos);
581           pos += 2;
582           if (slen > end - pos || slen < 3 + 1) {
583                     p2p_dbg(p2p, "Invalid ANQP Query Response length");
584                     return;
585           }
586 
587           if (WPA_GET_BE32(pos) != P2P_IE_VENDOR_TYPE) {
588                     p2p_dbg(p2p, "Unsupported ANQP vendor OUI-type %08x",
589                               WPA_GET_BE32(pos));
590                     return;
591           }
592           pos += 4;
593 
594           if (end - pos < 2)
595                     return;
596           update_indic = WPA_GET_LE16(pos);
597           p2p_dbg(p2p, "Service Update Indicator: %u", update_indic);
598           pos += 2;
599 
600           p2p->sd_peer = NULL;
601 
602           if (p2p->sd_query) {
603                     if (!p2p->sd_query->for_all_peers) {
604                               struct p2p_sd_query *q;
605                               p2p_dbg(p2p, "Remove completed SD query %p",
606                                         p2p->sd_query);
607                               q = p2p->sd_query;
608                               p2p_unlink_sd_query(p2p, p2p->sd_query);
609                               p2p_free_sd_query(q);
610                     }
611                     p2p->sd_query = NULL;
612           }
613 
614           if (p2p->cfg->sd_response)
615                     p2p->cfg->sd_response(p2p->cfg->cb_ctx, sa, update_indic,
616                                               pos, end - pos);
617           p2p_continue_find(p2p);
618 }
619 
620 
p2p_rx_gas_comeback_req(struct p2p_data * p2p,const u8 * sa,const u8 * data,size_t len,int rx_freq)621 void p2p_rx_gas_comeback_req(struct p2p_data *p2p, const u8 *sa,
622                                    const u8 *data, size_t len, int rx_freq)
623 {
624           struct wpabuf *resp;
625           u8 dialog_token;
626           size_t frag_len, max_len;
627           int more = 0;
628           unsigned int wait_time = 200;
629 
630           wpa_hexdump(MSG_DEBUG, "P2P: RX GAS Comeback Request", data, len);
631           if (len < 1)
632                     return;
633           dialog_token = *data;
634           p2p_dbg(p2p, "Dialog Token: %u", dialog_token);
635           if (dialog_token != p2p->sd_resp_dialog_token) {
636                     p2p_dbg(p2p, "No pending SD response fragment for dialog token %u",
637                               dialog_token);
638                     return;
639           }
640 
641           if (p2p->sd_resp == NULL) {
642                     p2p_dbg(p2p, "No pending SD response fragment available");
643                     return;
644           }
645           if (os_memcmp(sa, p2p->sd_resp_addr, ETH_ALEN) != 0) {
646                     p2p_dbg(p2p, "No pending SD response fragment for " MACSTR,
647                               MAC2STR(sa));
648                     return;
649           }
650 
651           /*
652            * In the 60 GHz, we have a smaller maximum frame length for management
653            * frames.
654            */
655           max_len = (rx_freq > 56160) ? 928 : 1400;
656           frag_len = wpabuf_len(p2p->sd_resp) - p2p->sd_resp_pos;
657           if (frag_len > max_len) {
658                     frag_len = max_len;
659                     more = 1;
660           }
661           resp = p2p_build_gas_comeback_resp(dialog_token, WLAN_STATUS_SUCCESS,
662                                                      p2p->srv_update_indic,
663                                                      wpabuf_head_u8(p2p->sd_resp) +
664                                                      p2p->sd_resp_pos, frag_len,
665                                                      p2p->sd_frag_id, more,
666                                                      wpabuf_len(p2p->sd_resp));
667           if (resp == NULL)
668                     return;
669           p2p_dbg(p2p, "Send GAS Comeback Response (frag_id %d more=%d frag_len=%d)",
670                     p2p->sd_frag_id, more, (int) frag_len);
671           p2p->sd_frag_id++;
672           p2p->sd_resp_pos += frag_len;
673 
674           if (more) {
675                     p2p_dbg(p2p, "%d more bytes remain to be sent",
676                               (int) (wpabuf_len(p2p->sd_resp) - p2p->sd_resp_pos));
677           } else {
678                     p2p_dbg(p2p, "All fragments of SD response sent");
679                     wpabuf_free(p2p->sd_resp);
680                     p2p->sd_resp = NULL;
681                     wait_time = 0; /* no more SD frames in the sequence */
682           }
683 
684           p2p->pending_action_state = P2P_NO_PENDING_ACTION;
685           if (p2p_send_action(p2p, rx_freq, sa, p2p->cfg->dev_addr,
686                                   p2p->cfg->dev_addr,
687                                   wpabuf_head(resp), wpabuf_len(resp), wait_time) < 0)
688                     p2p_dbg(p2p, "Failed to send Action frame");
689 
690           wpabuf_free(resp);
691 }
692 
693 
p2p_rx_gas_comeback_resp(struct p2p_data * p2p,const u8 * sa,const u8 * data,size_t len,int rx_freq)694 void p2p_rx_gas_comeback_resp(struct p2p_data *p2p, const u8 *sa,
695                                     const u8 *data, size_t len, int rx_freq)
696 {
697           const u8 *pos = data;
698           const u8 *end = data + len;
699           const u8 *next;
700           u8 dialog_token;
701           u16 status_code;
702           u8 frag_id;
703           u8 more_frags;
704           u16 comeback_delay;
705           u16 slen;
706 
707           wpa_hexdump(MSG_DEBUG, "P2P: RX GAS Comeback Response", data, len);
708 
709           if (p2p->state != P2P_SD_DURING_FIND || p2p->sd_peer == NULL ||
710               os_memcmp(sa, p2p->sd_peer->info.p2p_device_addr, ETH_ALEN) != 0) {
711                     p2p_dbg(p2p, "Ignore unexpected GAS Comeback Response from "
712                               MACSTR, MAC2STR(sa));
713                     return;
714           }
715           p2p->cfg->send_action_done(p2p->cfg->cb_ctx);
716           p2p_clear_timeout(p2p);
717 
718           p2p_dbg(p2p, "Received GAS Comeback Response from " MACSTR " (len=%d)",
719                     MAC2STR(sa), (int) len);
720 
721           if (len < 6 + 2) {
722                     p2p_dbg(p2p, "Too short GAS Comeback Response frame");
723                     return;
724           }
725 
726           dialog_token = *pos++;
727           /* TODO: check dialog_token match */
728           status_code = WPA_GET_LE16(pos);
729           pos += 2;
730           frag_id = *pos & 0x7f;
731           more_frags = (*pos & 0x80) >> 7;
732           pos++;
733           comeback_delay = WPA_GET_LE16(pos);
734           pos += 2;
735           p2p_dbg(p2p, "dialog_token=%u status_code=%u frag_id=%d more_frags=%d "
736                     "comeback_delay=%u",
737                     dialog_token, status_code, frag_id, more_frags,
738                     comeback_delay);
739           /* TODO: check frag_id match */
740           if (status_code) {
741                     p2p_dbg(p2p, "Service Discovery failed: status code %u",
742                               status_code);
743                     return;
744           }
745 
746           if (*pos != WLAN_EID_ADV_PROTO) {
747                     p2p_dbg(p2p, "Unexpected IE in GAS Comeback Response: %u",
748                               *pos);
749                     return;
750           }
751           pos++;
752 
753           slen = *pos++;
754           if (slen > end - pos || slen < 2) {
755                     p2p_dbg(p2p, "Invalid IE in GAS Comeback Response");
756                     return;
757           }
758           next = pos + slen;
759           pos++; /* skip QueryRespLenLimit and PAME-BI */
760 
761           if (*pos != ACCESS_NETWORK_QUERY_PROTOCOL) {
762                     p2p_dbg(p2p, "Unsupported GAS advertisement protocol id %u",
763                               *pos);
764                     return;
765           }
766 
767           pos = next;
768           /* Query Response */
769           if (end - pos < 2) {
770                     p2p_dbg(p2p, "Too short Query Response");
771                     return;
772           }
773           slen = WPA_GET_LE16(pos);
774           pos += 2;
775           p2p_dbg(p2p, "Query Response Length: %d", slen);
776           if (slen > end - pos) {
777                     p2p_dbg(p2p, "Not enough Query Response data");
778                     return;
779           }
780           if (slen == 0) {
781                     p2p_dbg(p2p, "No Query Response data");
782                     return;
783           }
784           end = pos + slen;
785 
786           if (p2p->sd_rx_resp) {
787                      /*
788                       * ANQP header is only included in the first fragment; rest of
789                       * the fragments start with continue TLVs.
790                       */
791                     goto skip_nqp_header;
792           }
793 
794           /* ANQP Query Response */
795           if (end - pos < 4)
796                     return;
797           if (WPA_GET_LE16(pos) != ANQP_VENDOR_SPECIFIC) {
798                     p2p_dbg(p2p, "Unsupported ANQP Info ID %u", WPA_GET_LE16(pos));
799                     return;
800           }
801           pos += 2;
802 
803           slen = WPA_GET_LE16(pos);
804           pos += 2;
805           p2p_dbg(p2p, "ANQP Query Response length: %u", slen);
806           if (slen < 3 + 1) {
807                     p2p_dbg(p2p, "Invalid ANQP Query Response length");
808                     return;
809           }
810           if (end - pos < 4)
811                     return;
812 
813           if (WPA_GET_BE32(pos) != P2P_IE_VENDOR_TYPE) {
814                     p2p_dbg(p2p, "Unsupported ANQP vendor OUI-type %08x",
815                               WPA_GET_BE32(pos));
816                     return;
817           }
818           pos += 4;
819 
820           if (end - pos < 2)
821                     return;
822           p2p->sd_rx_update_indic = WPA_GET_LE16(pos);
823           p2p_dbg(p2p, "Service Update Indicator: %u", p2p->sd_rx_update_indic);
824           pos += 2;
825 
826 skip_nqp_header:
827           if (wpabuf_resize(&p2p->sd_rx_resp, end - pos) < 0)
828                     return;
829           wpabuf_put_data(p2p->sd_rx_resp, pos, end - pos);
830           p2p_dbg(p2p, "Current SD reassembly buffer length: %u",
831                     (unsigned int) wpabuf_len(p2p->sd_rx_resp));
832 
833           if (more_frags) {
834                     p2p_dbg(p2p, "More fragments remains");
835                     /* TODO: what would be a good size limit? */
836                     if (wpabuf_len(p2p->sd_rx_resp) > 64000) {
837                               wpabuf_free(p2p->sd_rx_resp);
838                               p2p->sd_rx_resp = NULL;
839                               p2p_dbg(p2p, "Too long SD response - drop it");
840                               return;
841                     }
842                     p2p_send_gas_comeback_req(p2p, sa, dialog_token, rx_freq);
843                     return;
844           }
845 
846           p2p->sd_peer = NULL;
847 
848           if (p2p->sd_query) {
849                     if (!p2p->sd_query->for_all_peers) {
850                               struct p2p_sd_query *q;
851                               p2p_dbg(p2p, "Remove completed SD query %p",
852                                         p2p->sd_query);
853                               q = p2p->sd_query;
854                               p2p_unlink_sd_query(p2p, p2p->sd_query);
855                               p2p_free_sd_query(q);
856                     }
857                     p2p->sd_query = NULL;
858           }
859 
860           if (p2p->cfg->sd_response)
861                     p2p->cfg->sd_response(p2p->cfg->cb_ctx, sa,
862                                               p2p->sd_rx_update_indic,
863                                               wpabuf_head(p2p->sd_rx_resp),
864                                               wpabuf_len(p2p->sd_rx_resp));
865           wpabuf_free(p2p->sd_rx_resp);
866           p2p->sd_rx_resp = NULL;
867 
868           p2p_continue_find(p2p);
869 }
870 
871 
p2p_sd_request(struct p2p_data * p2p,const u8 * dst,const struct wpabuf * tlvs)872 void * p2p_sd_request(struct p2p_data *p2p, const u8 *dst,
873                           const struct wpabuf *tlvs)
874 {
875           struct p2p_sd_query *q;
876 
877           q = os_zalloc(sizeof(*q));
878           if (q == NULL)
879                     return NULL;
880 
881           if (dst)
882                     os_memcpy(q->peer, dst, ETH_ALEN);
883           else
884                     q->for_all_peers = 1;
885 
886           q->tlvs = wpabuf_dup(tlvs);
887           if (q->tlvs == NULL) {
888                     p2p_free_sd_query(q);
889                     return NULL;
890           }
891 
892           q->next = p2p->sd_queries;
893           p2p->sd_queries = q;
894           p2p_dbg(p2p, "Added SD Query %p", q);
895 
896           if (dst == NULL) {
897                     struct p2p_device *dev;
898 
899                     p2p->num_p2p_sd_queries++;
900 
901                     /* Update all the devices for the newly added broadcast query */
902                     dl_list_for_each(dev, &p2p->devices, struct p2p_device, list) {
903                               if (dev->sd_pending_bcast_queries <= 0)
904                                         dev->sd_pending_bcast_queries = 1;
905                               else
906                                         dev->sd_pending_bcast_queries++;
907                     }
908           }
909 
910           return q;
911 }
912 
913 
914 #ifdef CONFIG_WIFI_DISPLAY
p2p_sd_request_wfd(struct p2p_data * p2p,const u8 * dst,const struct wpabuf * tlvs)915 void * p2p_sd_request_wfd(struct p2p_data *p2p, const u8 *dst,
916                                 const struct wpabuf *tlvs)
917 {
918           struct p2p_sd_query *q;
919           q = p2p_sd_request(p2p, dst, tlvs);
920           if (q)
921                     q->wsd = 1;
922           return q;
923 }
924 #endif /* CONFIG_WIFI_DISPLAY */
925 
926 
p2p_sd_service_update(struct p2p_data * p2p)927 void p2p_sd_service_update(struct p2p_data *p2p)
928 {
929           p2p->srv_update_indic++;
930 }
931 
932 
p2p_sd_cancel_request(struct p2p_data * p2p,void * req)933 int p2p_sd_cancel_request(struct p2p_data *p2p, void *req)
934 {
935           if (p2p_unlink_sd_query(p2p, req)) {
936                     p2p_dbg(p2p, "Cancel pending SD query %p", req);
937                     p2p_free_sd_query(req);
938                     return 0;
939           }
940           return -1;
941 }
942