p2p_group.c revision dca3979ccdf869f140f096b83df322a0efc84f22
1/*
2 * Wi-Fi Direct - P2P group operations
3 * Copyright (c) 2009-2010, Atheros Communications
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 *
9 * Alternatively, this software may be distributed under the terms of BSD
10 * license.
11 *
12 * See README and COPYING for more details.
13 */
14
15#include "includes.h"
16
17#include "common.h"
18#include "common/ieee802_11_defs.h"
19#include "common/ieee802_11_common.h"
20#include "wps/wps_defs.h"
21#include "wps/wps_i.h"
22#include "p2p_i.h"
23#include "p2p.h"
24
25
26struct p2p_group_member {
27	struct p2p_group_member *next;
28	u8 addr[ETH_ALEN]; /* P2P Interface Address */
29	u8 dev_addr[ETH_ALEN]; /* P2P Device Address */
30	struct wpabuf *p2p_ie;
31	struct wpabuf *client_info;
32	u8 dev_capab;
33};
34
35/**
36 * struct p2p_group - Internal P2P module per-group data
37 */
38struct p2p_group {
39	struct p2p_data *p2p;
40	struct p2p_group_config *cfg;
41	struct p2p_group_member *members;
42	unsigned int num_members;
43	int group_formation;
44	int beacon_update;
45	struct wpabuf *noa;
46};
47
48
49static void p2p_group_update_ies(struct p2p_group *group);
50
51
52struct p2p_group * p2p_group_init(struct p2p_data *p2p,
53				  struct p2p_group_config *config)
54{
55	struct p2p_group *group, **groups;
56
57	group = os_zalloc(sizeof(*group));
58	if (group == NULL)
59		return NULL;
60
61	groups = os_realloc(p2p->groups, (p2p->num_groups + 1) *
62			    sizeof(struct p2p_group *));
63	if (groups == NULL) {
64		os_free(group);
65		return NULL;
66	}
67	groups[p2p->num_groups++] = group;
68	p2p->groups = groups;
69
70	group->p2p = p2p;
71	group->cfg = config;
72	group->group_formation = 1;
73	group->beacon_update = 1;
74	p2p_group_update_ies(group);
75	group->cfg->idle_update(group->cfg->cb_ctx, 1);
76
77	return group;
78}
79
80
81static void p2p_group_free_member(struct p2p_group_member *m)
82{
83	wpabuf_free(m->p2p_ie);
84	wpabuf_free(m->client_info);
85	os_free(m);
86}
87
88
89static void p2p_group_free_members(struct p2p_group *group)
90{
91	struct p2p_group_member *m, *prev;
92	m = group->members;
93	group->members = NULL;
94	group->num_members = 0;
95	while (m) {
96		prev = m;
97		m = m->next;
98		p2p_group_free_member(prev);
99	}
100}
101
102
103void p2p_group_deinit(struct p2p_group *group)
104{
105	size_t g;
106	struct p2p_data *p2p;
107
108	if (group == NULL)
109		return;
110
111	p2p = group->p2p;
112
113	for (g = 0; g < p2p->num_groups; g++) {
114		if (p2p->groups[g] == group) {
115			while (g + 1 < p2p->num_groups) {
116				p2p->groups[g] = p2p->groups[g + 1];
117				g++;
118			}
119			p2p->num_groups--;
120			break;
121		}
122	}
123
124	p2p_group_free_members(group);
125	os_free(group->cfg);
126	wpabuf_free(group->noa);
127	os_free(group);
128}
129
130
131static void p2p_client_info(struct wpabuf *ie, struct p2p_group_member *m)
132{
133	if (m->client_info == NULL)
134		return;
135	if (wpabuf_tailroom(ie) < wpabuf_len(m->client_info) + 1)
136		return;
137	wpabuf_put_buf(ie, m->client_info);
138}
139
140
141static void p2p_group_add_common_ies(struct p2p_group *group,
142				     struct wpabuf *ie)
143{
144	u8 dev_capab = 0, group_capab = 0;
145
146	/* P2P Capability */
147	dev_capab |= P2P_DEV_CAPAB_SERVICE_DISCOVERY;
148	dev_capab |= P2P_DEV_CAPAB_INVITATION_PROCEDURE;
149	group_capab |= P2P_GROUP_CAPAB_GROUP_OWNER;
150	if (group->cfg->persistent_group)
151		group_capab |= P2P_GROUP_CAPAB_PERSISTENT_GROUP;
152	if (group->p2p->cfg->p2p_intra_bss)
153		group_capab |= P2P_GROUP_CAPAB_INTRA_BSS_DIST;
154	if (group->group_formation)
155		group_capab |= P2P_GROUP_CAPAB_GROUP_FORMATION;
156	if (group->p2p->cross_connect)
157		group_capab |= P2P_GROUP_CAPAB_CROSS_CONN;
158	if (group->num_members >= group->cfg->max_clients)
159		group_capab |= P2P_GROUP_CAPAB_GROUP_LIMIT;
160	p2p_buf_add_capability(ie, dev_capab, group_capab);
161}
162
163
164static void p2p_group_add_noa(struct wpabuf *ie, struct wpabuf *noa)
165{
166	if (noa == NULL)
167		return;
168	/* Notice of Absence */
169	wpabuf_put_u8(ie, P2P_ATTR_NOTICE_OF_ABSENCE);
170	wpabuf_put_le16(ie, wpabuf_len(noa));
171	wpabuf_put_buf(ie, noa);
172}
173
174
175static struct wpabuf * p2p_group_build_beacon_ie(struct p2p_group *group)
176{
177	struct wpabuf *ie;
178	u8 *len;
179
180	ie = wpabuf_alloc(257);
181	if (ie == NULL)
182		return NULL;
183
184	len = p2p_buf_add_ie_hdr(ie);
185	p2p_group_add_common_ies(group, ie);
186#ifdef ANDROID_BRCM_P2P_PATCH
187	/* P2P_ADDR: Use p2p_dev_addr instead of own mac addr*/
188	p2p_buf_add_device_id(ie, group->p2p->cfg->p2p_dev_addr);
189#else
190	p2p_buf_add_device_id(ie, group->p2p->cfg->dev_addr);
191#endif
192	p2p_group_add_noa(ie, group->noa);
193	p2p_buf_update_ie_hdr(ie, len);
194
195	return ie;
196}
197
198
199static struct wpabuf * p2p_group_build_probe_resp_ie(struct p2p_group *group)
200{
201	u8 *group_info;
202	struct wpabuf *ie;
203	struct p2p_group_member *m;
204	u8 *len;
205
206	ie = wpabuf_alloc(257);
207	if (ie == NULL)
208		return NULL;
209
210	len = p2p_buf_add_ie_hdr(ie);
211
212	p2p_group_add_common_ies(group, ie);
213	p2p_group_add_noa(ie, group->noa);
214
215	/* P2P Device Info */
216	p2p_buf_add_device_info(ie, group->p2p, NULL);
217
218	/* P2P Group Info */
219	group_info = wpabuf_put(ie, 0);
220	wpabuf_put_u8(ie, P2P_ATTR_GROUP_INFO);
221	wpabuf_put_le16(ie, 0); /* Length to be filled */
222	for (m = group->members; m; m = m->next)
223		p2p_client_info(ie, m);
224	WPA_PUT_LE16(group_info + 1,
225		     (u8 *) wpabuf_put(ie, 0) - group_info - 3);
226
227	p2p_buf_update_ie_hdr(ie, len);
228	return ie;
229}
230
231
232static void p2p_group_update_ies(struct p2p_group *group)
233{
234	struct wpabuf *beacon_ie;
235	struct wpabuf *probe_resp_ie;
236
237	probe_resp_ie = p2p_group_build_probe_resp_ie(group);
238	if (probe_resp_ie == NULL)
239		return;
240	wpa_hexdump_buf(MSG_MSGDUMP, "P2P: Update GO Probe Response P2P IE",
241			probe_resp_ie);
242
243	if (group->beacon_update) {
244		beacon_ie = p2p_group_build_beacon_ie(group);
245		if (beacon_ie)
246			group->beacon_update = 0;
247		wpa_hexdump_buf(MSG_MSGDUMP, "P2P: Update GO Beacon P2P IE",
248				beacon_ie);
249	} else
250		beacon_ie = NULL;
251
252	group->cfg->ie_update(group->cfg->cb_ctx, beacon_ie, probe_resp_ie);
253}
254
255
256/**
257 * p2p_build_client_info - Build P2P Client Info Descriptor
258 * @addr: MAC address of the peer device
259 * @p2p_ie: P2P IE from (Re)Association Request
260 * @dev_capab: Buffer for returning Device Capability
261 * @dev_addr: Buffer for returning P2P Device Address
262 * Returns: P2P Client Info Descriptor or %NULL on failure
263 *
264 * This function builds P2P Client Info Descriptor based on the information
265 * available from (Re)Association Request frame. Group owner can use this to
266 * build the P2P Group Info attribute for Probe Response frames.
267 */
268static struct wpabuf * p2p_build_client_info(const u8 *addr,
269					     struct wpabuf *p2p_ie,
270					     u8 *dev_capab, u8 *dev_addr)
271{
272	const u8 *spos;
273	struct p2p_message msg;
274	u8 *len_pos;
275	struct wpabuf *buf;
276
277	if (p2p_ie == NULL)
278		return NULL;
279
280	os_memset(&msg, 0, sizeof(msg));
281	if (p2p_parse_p2p_ie(p2p_ie, &msg) ||
282	    msg.capability == NULL || msg.p2p_device_info == NULL)
283		return NULL;
284
285	buf = wpabuf_alloc(ETH_ALEN + 1 + 1 + msg.p2p_device_info_len);
286	if (buf == NULL)
287		return NULL;
288
289	*dev_capab = msg.capability[0];
290	os_memcpy(dev_addr, msg.p2p_device_addr, ETH_ALEN);
291
292	spos = msg.p2p_device_info; /* P2P Device address */
293
294	/* P2P Client Info Descriptor */
295	/* Length to be set */
296	len_pos = wpabuf_put(buf, 1);
297	/* P2P Device address */
298	wpabuf_put_data(buf, spos, ETH_ALEN);
299	/* P2P Interface address */
300	wpabuf_put_data(buf, addr, ETH_ALEN);
301	/* Device Capability Bitmap */
302	wpabuf_put_u8(buf, msg.capability[0]);
303	/*
304	 * Config Methods, Primary Device Type, Number of Secondary Device
305	 * Types, Secondary Device Type List, Device Name copied from
306	 * Device Info
307	 */
308	wpabuf_put_data(buf, spos + ETH_ALEN,
309			msg.p2p_device_info_len - ETH_ALEN);
310
311	*len_pos = wpabuf_len(buf) - 1;
312
313
314	return buf;
315}
316
317
318int p2p_group_notif_assoc(struct p2p_group *group, const u8 *addr,
319			  const u8 *ie, size_t len)
320{
321	struct p2p_group_member *m;
322
323	if (group == NULL)
324		return -1;
325
326	m = os_zalloc(sizeof(*m));
327	if (m == NULL)
328		return -1;
329	os_memcpy(m->addr, addr, ETH_ALEN);
330	m->p2p_ie = ieee802_11_vendor_ie_concat(ie, len, P2P_IE_VENDOR_TYPE);
331	if (m->p2p_ie) {
332		m->client_info = p2p_build_client_info(addr, m->p2p_ie,
333						       &m->dev_capab,
334						       m->dev_addr);
335	}
336
337	m->next = group->members;
338	group->members = m;
339	group->num_members++;
340	wpa_msg(group->p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Add client " MACSTR
341		" to group (p2p=%d client_info=%d); num_members=%u/%u",
342		MAC2STR(addr), m->p2p_ie ? 1 : 0, m->client_info ? 1 : 0,
343		group->num_members, group->cfg->max_clients);
344	if (group->num_members == group->cfg->max_clients)
345		group->beacon_update = 1;
346	p2p_group_update_ies(group);
347	if (group->num_members == 1)
348		group->cfg->idle_update(group->cfg->cb_ctx, 0);
349
350	return 0;
351}
352
353
354struct wpabuf * p2p_group_assoc_resp_ie(struct p2p_group *group, u8 status)
355{
356	struct wpabuf *resp;
357	u8 *rlen;
358
359	/*
360	 * (Re)Association Response - P2P IE
361	 * Status attribute (shall be present when association request is
362	 *	denied)
363	 * Extended Listen Timing (may be present)
364	 */
365	resp = wpabuf_alloc(20);
366	if (resp == NULL)
367		return NULL;
368	rlen = p2p_buf_add_ie_hdr(resp);
369	if (status != P2P_SC_SUCCESS)
370		p2p_buf_add_status(resp, status);
371	p2p_buf_update_ie_hdr(resp, rlen);
372
373	return resp;
374}
375
376
377void p2p_group_notif_disassoc(struct p2p_group *group, const u8 *addr)
378{
379	struct p2p_group_member *m, *prev;
380
381	if (group == NULL)
382		return;
383
384	m = group->members;
385	prev = NULL;
386	while (m) {
387		if (os_memcmp(m->addr, addr, ETH_ALEN) == 0)
388			break;
389		prev = m;
390		m = m->next;
391	}
392
393	if (m) {
394		if (prev)
395			prev->next = m->next;
396		else
397			group->members = m->next;
398		p2p_group_free_member(m);
399		group->num_members--;
400		wpa_msg(group->p2p->cfg->msg_ctx, MSG_DEBUG, "P2P: Remove "
401			"client " MACSTR " from group; num_members=%u/%u",
402			MAC2STR(addr), group->num_members,
403			group->cfg->max_clients);
404		if (group->num_members == group->cfg->max_clients - 1)
405			group->beacon_update = 1;
406		p2p_group_update_ies(group);
407		if (group->num_members == 0)
408			group->cfg->idle_update(group->cfg->cb_ctx, 1);
409	}
410}
411
412
413/**
414 * p2p_match_dev_type_member - Match client device type with requested type
415 * @m: Group member
416 * @wps: WPS TLVs from Probe Request frame (concatenated WPS IEs)
417 * Returns: 1 on match, 0 on mismatch
418 *
419 * This function can be used to match the Requested Device Type attribute in
420 * WPS IE with the device types of a group member for deciding whether a GO
421 * should reply to a Probe Request frame.
422 */
423static int p2p_match_dev_type_member(struct p2p_group_member *m,
424				     struct wpabuf *wps)
425{
426	const u8 *pos, *end;
427	struct wps_parse_attr attr;
428	u8 num_sec;
429
430	if (m->client_info == NULL || wps == NULL)
431		return 0;
432
433	pos = wpabuf_head(m->client_info);
434	end = pos + wpabuf_len(m->client_info);
435
436	pos += 1 + 2 * ETH_ALEN + 1 + 2;
437	if (end - pos < WPS_DEV_TYPE_LEN + 1)
438		return 0;
439
440	if (wps_parse_msg(wps, &attr))
441		return 1; /* assume no Requested Device Type attributes */
442
443	if (attr.num_req_dev_type == 0)
444		return 1; /* no Requested Device Type attributes -> match */
445
446	if (dev_type_list_match(pos, attr.req_dev_type, attr.num_req_dev_type))
447		return 1; /* Match with client Primary Device Type */
448
449	pos += WPS_DEV_TYPE_LEN;
450	num_sec = *pos++;
451	if (end - pos < num_sec * WPS_DEV_TYPE_LEN)
452		return 0;
453	while (num_sec > 0) {
454		num_sec--;
455		if (dev_type_list_match(pos, attr.req_dev_type,
456					attr.num_req_dev_type))
457			return 1; /* Match with client Secondary Device Type */
458		pos += WPS_DEV_TYPE_LEN;
459	}
460
461	/* No matching device type found */
462	return 0;
463}
464
465
466int p2p_group_match_dev_type(struct p2p_group *group, struct wpabuf *wps)
467{
468	struct p2p_group_member *m;
469
470	if (p2p_match_dev_type(group->p2p, wps))
471		return 1; /* Match with own device type */
472
473	for (m = group->members; m; m = m->next) {
474		if (p2p_match_dev_type_member(m, wps))
475			return 1; /* Match with group client device type */
476	}
477
478	/* No match with Requested Device Type */
479	return 0;
480}
481
482
483void p2p_group_notif_formation_done(struct p2p_group *group)
484{
485	if (group == NULL)
486		return;
487	group->group_formation = 0;
488	group->beacon_update = 1;
489	p2p_group_update_ies(group);
490}
491
492
493int p2p_group_notif_noa(struct p2p_group *group, const u8 *noa,
494			size_t noa_len)
495{
496	if (noa == NULL) {
497		wpabuf_free(group->noa);
498		group->noa = NULL;
499	} else {
500		if (group->noa) {
501			if (wpabuf_size(group->noa) >= noa_len) {
502				group->noa->size = 0;
503				wpabuf_put_data(group->noa, noa, noa_len);
504			} else {
505				wpabuf_free(group->noa);
506				group->noa = NULL;
507			}
508		}
509
510		if (!group->noa) {
511			group->noa = wpabuf_alloc_copy(noa, noa_len);
512			if (group->noa == NULL)
513				return -1;
514		}
515	}
516
517	group->beacon_update = 1;
518	p2p_group_update_ies(group);
519	return 0;
520}
521
522
523static struct p2p_group_member * p2p_group_get_client(struct p2p_group *group,
524						      const u8 *dev_id)
525{
526	struct p2p_group_member *m;
527
528	for (m = group->members; m; m = m->next) {
529		if (os_memcmp(dev_id, m->dev_addr, ETH_ALEN) == 0)
530			return m;
531	}
532
533	return NULL;
534}
535
536
537static struct p2p_group_member * p2p_group_get_client_iface(
538	struct p2p_group *group, const u8 *interface_addr)
539{
540	struct p2p_group_member *m;
541
542	for (m = group->members; m; m = m->next) {
543		if (os_memcmp(interface_addr, m->addr, ETH_ALEN) == 0)
544			return m;
545	}
546
547	return NULL;
548}
549
550#ifdef ANDROID_BRCM_P2P_PATCH
551u8 * p2p_group_get_dev_addr(struct p2p_group *group, const u8 *addr)
552{
553	struct p2p_group_member *m;
554
555	m = p2p_group_get_client_iface(group, addr);
556
557	if (m)
558		return m->dev_addr;
559	else
560		return NULL;
561}
562#endif /* ANDROID_BRCM_P2P_PATCH */
563
564static struct wpabuf * p2p_build_go_disc_req(void)
565{
566	struct wpabuf *buf;
567
568	buf = wpabuf_alloc(100);
569	if (buf == NULL)
570		return NULL;
571
572	p2p_buf_add_action_hdr(buf, P2P_GO_DISC_REQ, 0);
573
574	return buf;
575}
576
577
578int p2p_group_go_discover(struct p2p_group *group, const u8 *dev_id,
579			  const u8 *searching_dev, int rx_freq)
580{
581	struct p2p_group_member *m;
582	struct wpabuf *req;
583	struct p2p_data *p2p = group->p2p;
584	int freq;
585
586	m = p2p_group_get_client(group, dev_id);
587	if (m == NULL || m->client_info == NULL) {
588		wpa_printf(MSG_DEBUG, "P2P: Requested client was not in this "
589			   "group " MACSTR,
590			   MAC2STR(group->cfg->interface_addr));
591		return -1;
592	}
593
594	if (!(m->dev_capab & P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY)) {
595		wpa_printf(MSG_DEBUG, "P2P: Requested client does not support "
596			   "client discoverability");
597		return -1;
598	}
599
600	wpa_printf(MSG_DEBUG, "P2P: Schedule GO Discoverability Request to be "
601		   "sent to " MACSTR, MAC2STR(dev_id));
602
603	req = p2p_build_go_disc_req();
604	if (req == NULL)
605		return -1;
606
607	/* TODO: Should really use group operating frequency here */
608	freq = rx_freq;
609
610	p2p->pending_action_state = P2P_PENDING_GO_DISC_REQ;
611	if (p2p->cfg->send_action(p2p->cfg->cb_ctx, freq, m->addr,
612				  group->cfg->interface_addr,
613				  group->cfg->interface_addr,
614				  wpabuf_head(req), wpabuf_len(req), 200) < 0)
615	{
616		wpa_msg(p2p->cfg->msg_ctx, MSG_DEBUG,
617			"P2P: Failed to send Action frame");
618	}
619
620	wpabuf_free(req);
621
622	return 0;
623}
624
625
626const u8 * p2p_group_get_interface_addr(struct p2p_group *group)
627{
628	return group->cfg->interface_addr;
629}
630
631
632u8 p2p_group_presence_req(struct p2p_group *group,
633			  const u8 *client_interface_addr,
634			  const u8 *noa, size_t noa_len)
635{
636	struct p2p_group_member *m;
637	u8 curr_noa[50];
638	int curr_noa_len;
639
640	m = p2p_group_get_client_iface(group, client_interface_addr);
641	if (m == NULL || m->client_info == NULL) {
642		wpa_printf(MSG_DEBUG, "P2P: Client was not in this group");
643		return P2P_SC_FAIL_UNABLE_TO_ACCOMMODATE;
644	}
645
646	wpa_hexdump(MSG_DEBUG, "P2P: Presence Request NoA", noa, noa_len);
647
648	if (group->p2p->cfg->get_noa)
649		curr_noa_len = group->p2p->cfg->get_noa(
650			group->p2p->cfg->cb_ctx, group->cfg->interface_addr,
651			curr_noa, sizeof(curr_noa));
652	else
653		curr_noa_len = -1;
654	if (curr_noa_len < 0)
655		wpa_printf(MSG_DEBUG, "P2P: Failed to fetch current NoA");
656	else if (curr_noa_len == 0)
657		wpa_printf(MSG_DEBUG, "P2P: No NoA being advertized");
658	else
659		wpa_hexdump(MSG_DEBUG, "P2P: Current NoA", curr_noa,
660			    curr_noa_len);
661
662	/* TODO: properly process request and store copy */
663	if (curr_noa_len > 0)
664		return P2P_SC_FAIL_UNABLE_TO_ACCOMMODATE;
665
666	return P2P_SC_SUCCESS;
667}
668
669
670unsigned int p2p_get_group_num_members(struct p2p_group *group)
671{
672	return group->num_members;
673}
674
675
676const u8 * p2p_iterate_group_members(struct p2p_group *group, void **next)
677{
678	struct p2p_group_member *iter = *next;
679
680	if (!iter)
681		iter = group->members;
682	else
683		iter = iter->next;
684
685	*next = iter;
686
687	if (!iter)
688		return NULL;
689
690	return iter->addr;
691}
692