1/*
2 * wpa_supplicant - IBSS RSN
3 * Copyright (c) 2009, Jouni Malinen <j@w1.fi>
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 "l2_packet/l2_packet.h"
13#include "rsn_supp/wpa.h"
14#include "rsn_supp/wpa_ie.h"
15#include "ap/wpa_auth.h"
16#include "wpa_supplicant_i.h"
17#include "driver_i.h"
18#include "ibss_rsn.h"
19
20
21static struct ibss_rsn_peer * ibss_rsn_get_peer(struct ibss_rsn *ibss_rsn,
22						const u8 *addr)
23{
24	struct ibss_rsn_peer *peer;
25
26	for (peer = ibss_rsn->peers; peer; peer = peer->next)
27		if (os_memcmp(addr, peer->addr, ETH_ALEN) == 0)
28			break;
29	return peer;
30}
31
32
33static void ibss_rsn_free(struct ibss_rsn_peer *peer)
34{
35	wpa_auth_sta_deinit(peer->auth);
36	wpa_sm_deinit(peer->supp);
37	os_free(peer);
38}
39
40
41static void supp_set_state(void *ctx, enum wpa_states state)
42{
43	struct ibss_rsn_peer *peer = ctx;
44	peer->supp_state = state;
45}
46
47
48static enum wpa_states supp_get_state(void *ctx)
49{
50	struct ibss_rsn_peer *peer = ctx;
51	return peer->supp_state;
52}
53
54
55static int supp_ether_send(void *ctx, const u8 *dest, u16 proto, const u8 *buf,
56			   size_t len)
57{
58	struct ibss_rsn_peer *peer = ctx;
59	struct wpa_supplicant *wpa_s = peer->ibss_rsn->wpa_s;
60
61	wpa_printf(MSG_DEBUG, "SUPP: %s(dest=" MACSTR " proto=0x%04x "
62		   "len=%lu)",
63		   __func__, MAC2STR(dest), proto, (unsigned long) len);
64
65	if (wpa_s->l2)
66		return l2_packet_send(wpa_s->l2, dest, proto, buf, len);
67
68	return wpa_drv_send_eapol(wpa_s, dest, proto, buf, len);
69}
70
71
72static u8 * supp_alloc_eapol(void *ctx, u8 type, const void *data,
73			     u16 data_len, size_t *msg_len, void **data_pos)
74{
75	struct ieee802_1x_hdr *hdr;
76
77	wpa_printf(MSG_DEBUG, "SUPP: %s(type=%d data_len=%d)",
78		   __func__, type, data_len);
79
80	*msg_len = sizeof(*hdr) + data_len;
81	hdr = os_malloc(*msg_len);
82	if (hdr == NULL)
83		return NULL;
84
85	hdr->version = 2;
86	hdr->type = type;
87	hdr->length = host_to_be16(data_len);
88
89	if (data)
90		os_memcpy(hdr + 1, data, data_len);
91	else
92		os_memset(hdr + 1, 0, data_len);
93
94	if (data_pos)
95		*data_pos = hdr + 1;
96
97	return (u8 *) hdr;
98}
99
100
101static int supp_get_beacon_ie(void *ctx)
102{
103	struct ibss_rsn_peer *peer = ctx;
104
105	wpa_printf(MSG_DEBUG, "SUPP: %s", __func__);
106	/* TODO: get correct RSN IE */
107	return wpa_sm_set_ap_rsn_ie(peer->supp,
108				    (u8 *) "\x30\x14\x01\x00"
109				    "\x00\x0f\xac\x04"
110				    "\x01\x00\x00\x0f\xac\x04"
111				    "\x01\x00\x00\x0f\xac\x02"
112				    "\x00\x00", 22);
113}
114
115
116static int supp_set_key(void *ctx, enum wpa_alg alg,
117			const u8 *addr, int key_idx, int set_tx,
118			const u8 *seq, size_t seq_len,
119			const u8 *key, size_t key_len)
120{
121	struct ibss_rsn_peer *peer = ctx;
122
123	wpa_printf(MSG_DEBUG, "SUPP: %s(alg=%d addr=" MACSTR " key_idx=%d "
124		   "set_tx=%d)",
125		   __func__, alg, MAC2STR(addr), key_idx, set_tx);
126	wpa_hexdump(MSG_DEBUG, "SUPP: set_key - seq", seq, seq_len);
127	wpa_hexdump_key(MSG_DEBUG, "SUPP: set_key - key", key, key_len);
128
129	if (key_idx == 0) {
130		/*
131		 * In IBSS RSN, the pairwise key from the 4-way handshake
132		 * initiated by the peer with highest MAC address is used.
133		 */
134		if (os_memcmp(peer->ibss_rsn->wpa_s->own_addr, peer->addr,
135			      ETH_ALEN) > 0) {
136			wpa_printf(MSG_DEBUG, "SUPP: Do not use this PTK");
137			return 0;
138		}
139	}
140
141	if (is_broadcast_ether_addr(addr))
142		addr = peer->addr;
143	return wpa_drv_set_key(peer->ibss_rsn->wpa_s, alg, addr, key_idx,
144			       set_tx, seq, seq_len, key, key_len);
145}
146
147
148static void * supp_get_network_ctx(void *ctx)
149{
150	struct ibss_rsn_peer *peer = ctx;
151	return wpa_supplicant_get_ssid(peer->ibss_rsn->wpa_s);
152}
153
154
155static int supp_mlme_setprotection(void *ctx, const u8 *addr,
156				   int protection_type, int key_type)
157{
158	wpa_printf(MSG_DEBUG, "SUPP: %s(addr=" MACSTR " protection_type=%d "
159		   "key_type=%d)",
160		   __func__, MAC2STR(addr), protection_type, key_type);
161	return 0;
162}
163
164
165static void supp_cancel_auth_timeout(void *ctx)
166{
167	wpa_printf(MSG_DEBUG, "SUPP: %s", __func__);
168}
169
170
171static void supp_deauthenticate(void * ctx, int reason_code)
172{
173	wpa_printf(MSG_DEBUG, "SUPP: %s (TODO)", __func__);
174}
175
176
177static int ibss_rsn_supp_init(struct ibss_rsn_peer *peer, const u8 *own_addr,
178			      const u8 *psk)
179{
180	struct wpa_sm_ctx *ctx = os_zalloc(sizeof(*ctx));
181	if (ctx == NULL)
182		return -1;
183
184	ctx->ctx = peer;
185	ctx->msg_ctx = peer->ibss_rsn->wpa_s;
186	ctx->set_state = supp_set_state;
187	ctx->get_state = supp_get_state;
188	ctx->ether_send = supp_ether_send;
189	ctx->get_beacon_ie = supp_get_beacon_ie;
190	ctx->alloc_eapol = supp_alloc_eapol;
191	ctx->set_key = supp_set_key;
192	ctx->get_network_ctx = supp_get_network_ctx;
193	ctx->mlme_setprotection = supp_mlme_setprotection;
194	ctx->cancel_auth_timeout = supp_cancel_auth_timeout;
195	ctx->deauthenticate = supp_deauthenticate;
196	peer->supp = wpa_sm_init(ctx);
197	if (peer->supp == NULL) {
198		wpa_printf(MSG_DEBUG, "SUPP: wpa_sm_init() failed");
199		return -1;
200	}
201
202	wpa_sm_set_own_addr(peer->supp, own_addr);
203	wpa_sm_set_param(peer->supp, WPA_PARAM_RSN_ENABLED, 1);
204	wpa_sm_set_param(peer->supp, WPA_PARAM_PROTO, WPA_PROTO_RSN);
205	wpa_sm_set_param(peer->supp, WPA_PARAM_PAIRWISE, WPA_CIPHER_CCMP);
206	wpa_sm_set_param(peer->supp, WPA_PARAM_GROUP, WPA_CIPHER_CCMP);
207	wpa_sm_set_param(peer->supp, WPA_PARAM_KEY_MGMT, WPA_KEY_MGMT_PSK);
208	wpa_sm_set_pmk(peer->supp, psk, PMK_LEN);
209
210	peer->supp_ie_len = sizeof(peer->supp_ie);
211	if (wpa_sm_set_assoc_wpa_ie_default(peer->supp, peer->supp_ie,
212					    &peer->supp_ie_len) < 0) {
213		wpa_printf(MSG_DEBUG, "SUPP: wpa_sm_set_assoc_wpa_ie_default()"
214			   " failed");
215		return -1;
216	}
217
218	wpa_sm_notify_assoc(peer->supp, peer->addr);
219
220	return 0;
221}
222
223
224static void auth_logger(void *ctx, const u8 *addr, logger_level level,
225			const char *txt)
226{
227	if (addr)
228		wpa_printf(MSG_DEBUG, "AUTH: " MACSTR " - %s",
229			   MAC2STR(addr), txt);
230	else
231		wpa_printf(MSG_DEBUG, "AUTH: %s", txt);
232}
233
234
235static const u8 * auth_get_psk(void *ctx, const u8 *addr, const u8 *prev_psk)
236{
237	struct ibss_rsn *ibss_rsn = ctx;
238	wpa_printf(MSG_DEBUG, "AUTH: %s (addr=" MACSTR " prev_psk=%p)",
239		   __func__, MAC2STR(addr), prev_psk);
240	if (prev_psk)
241		return NULL;
242	return ibss_rsn->psk;
243}
244
245
246static int auth_send_eapol(void *ctx, const u8 *addr, const u8 *data,
247			   size_t data_len, int encrypt)
248{
249	struct ibss_rsn *ibss_rsn = ctx;
250	struct wpa_supplicant *wpa_s = ibss_rsn->wpa_s;
251
252	wpa_printf(MSG_DEBUG, "AUTH: %s(addr=" MACSTR " data_len=%lu "
253		   "encrypt=%d)",
254		   __func__, MAC2STR(addr), (unsigned long) data_len, encrypt);
255
256	if (wpa_s->l2)
257		return l2_packet_send(wpa_s->l2, addr, ETH_P_EAPOL, data,
258				      data_len);
259
260	return wpa_drv_send_eapol(wpa_s, addr, ETH_P_EAPOL, data, data_len);
261}
262
263
264static int auth_set_key(void *ctx, int vlan_id, enum wpa_alg alg,
265			const u8 *addr, int idx, u8 *key, size_t key_len)
266{
267	struct ibss_rsn *ibss_rsn = ctx;
268	u8 seq[6];
269
270	os_memset(seq, 0, sizeof(seq));
271
272	if (addr) {
273		wpa_printf(MSG_DEBUG, "AUTH: %s(alg=%d addr=" MACSTR
274			   " key_idx=%d)",
275			   __func__, alg, MAC2STR(addr), idx);
276	} else {
277		wpa_printf(MSG_DEBUG, "AUTH: %s(alg=%d key_idx=%d)",
278			   __func__, alg, idx);
279	}
280	wpa_hexdump_key(MSG_DEBUG, "AUTH: set_key - key", key, key_len);
281
282	if (idx == 0) {
283		/*
284		 * In IBSS RSN, the pairwise key from the 4-way handshake
285		 * initiated by the peer with highest MAC address is used.
286		 */
287		if (addr == NULL ||
288		    os_memcmp(ibss_rsn->wpa_s->own_addr, addr, ETH_ALEN) < 0) {
289			wpa_printf(MSG_DEBUG, "AUTH: Do not use this PTK");
290			return 0;
291		}
292	}
293
294	return wpa_drv_set_key(ibss_rsn->wpa_s, alg, addr, idx,
295			       1, seq, 6, key, key_len);
296}
297
298
299static int auth_for_each_sta(void *ctx, int (*cb)(struct wpa_state_machine *sm,
300						  void *ctx),
301			     void *cb_ctx)
302{
303	struct ibss_rsn *ibss_rsn = ctx;
304	struct ibss_rsn_peer *peer;
305
306	wpa_printf(MSG_DEBUG, "AUTH: for_each_sta");
307
308	for (peer = ibss_rsn->peers; peer; peer = peer->next) {
309		if (peer->auth && cb(peer->auth, cb_ctx))
310			return 1;
311	}
312
313	return 0;
314}
315
316
317static void ibss_set_sta_authorized(struct ibss_rsn *ibss_rsn,
318				    struct ibss_rsn_peer *peer, int authorized)
319{
320	int res;
321
322	if (authorized) {
323		res = wpa_drv_sta_set_flags(ibss_rsn->wpa_s, peer->addr,
324					    WPA_STA_AUTHORIZED,
325					    WPA_STA_AUTHORIZED, ~0);
326		wpa_printf(MSG_DEBUG, "AUTH: " MACSTR " authorizing port",
327			   MAC2STR(peer->addr));
328	} else {
329		res = wpa_drv_sta_set_flags(ibss_rsn->wpa_s, peer->addr,
330					    0, 0, ~WPA_STA_AUTHORIZED);
331		wpa_printf(MSG_DEBUG, "AUTH: " MACSTR " unauthorizing port",
332			   MAC2STR(peer->addr));
333	}
334
335	if (res && errno != ENOENT) {
336		wpa_printf(MSG_DEBUG, "Could not set station " MACSTR " flags "
337			   "for kernel driver (errno=%d)",
338			   MAC2STR(peer->addr), errno);
339	}
340}
341
342
343static void auth_set_eapol(void *ctx, const u8 *addr,
344				       wpa_eapol_variable var, int value)
345{
346	struct ibss_rsn *ibss_rsn = ctx;
347	struct ibss_rsn_peer *peer = ibss_rsn_get_peer(ibss_rsn, addr);
348
349	if (peer == NULL)
350		return;
351
352	switch (var) {
353	case WPA_EAPOL_authorized:
354		ibss_set_sta_authorized(ibss_rsn, peer, value);
355		break;
356	default:
357		/* do not handle any other event */
358		wpa_printf(MSG_DEBUG, "AUTH: eapol event not handled %d", var);
359		break;
360	}
361}
362
363
364static int ibss_rsn_auth_init_group(struct ibss_rsn *ibss_rsn,
365				    const u8 *own_addr)
366{
367	struct wpa_auth_config conf;
368	struct wpa_auth_callbacks cb;
369
370	wpa_printf(MSG_DEBUG, "AUTH: Initializing group state machine");
371
372	os_memset(&conf, 0, sizeof(conf));
373	conf.wpa = 2;
374	conf.wpa_key_mgmt = WPA_KEY_MGMT_PSK;
375	conf.wpa_pairwise = WPA_CIPHER_CCMP;
376	conf.rsn_pairwise = WPA_CIPHER_CCMP;
377	conf.wpa_group = WPA_CIPHER_CCMP;
378	conf.eapol_version = 2;
379	conf.wpa_group_rekey = 600;
380
381	os_memset(&cb, 0, sizeof(cb));
382	cb.ctx = ibss_rsn;
383	cb.logger = auth_logger;
384	cb.set_eapol = auth_set_eapol;
385	cb.send_eapol = auth_send_eapol;
386	cb.get_psk = auth_get_psk;
387	cb.set_key = auth_set_key;
388	cb.for_each_sta = auth_for_each_sta;
389
390	ibss_rsn->auth_group = wpa_init(own_addr, &conf, &cb);
391	if (ibss_rsn->auth_group == NULL) {
392		wpa_printf(MSG_DEBUG, "AUTH: wpa_init() failed");
393		return -1;
394	}
395
396	wpa_init_keys(ibss_rsn->auth_group);
397
398	return 0;
399}
400
401
402static int ibss_rsn_auth_init(struct ibss_rsn *ibss_rsn,
403			      struct ibss_rsn_peer *peer)
404{
405	peer->auth = wpa_auth_sta_init(ibss_rsn->auth_group, peer->addr);
406	if (peer->auth == NULL) {
407		wpa_printf(MSG_DEBUG, "AUTH: wpa_auth_sta_init() failed");
408		return -1;
409	}
410
411	/* TODO: get peer RSN IE with Probe Request */
412	if (wpa_validate_wpa_ie(ibss_rsn->auth_group, peer->auth,
413				(u8 *) "\x30\x14\x01\x00"
414				"\x00\x0f\xac\x04"
415				"\x01\x00\x00\x0f\xac\x04"
416				"\x01\x00\x00\x0f\xac\x02"
417				"\x00\x00", 22, NULL, 0) !=
418	    WPA_IE_OK) {
419		wpa_printf(MSG_DEBUG, "AUTH: wpa_validate_wpa_ie() failed");
420		return -1;
421	}
422
423	if (wpa_auth_sm_event(peer->auth, WPA_ASSOC))
424		return -1;
425
426	if (wpa_auth_sta_associated(ibss_rsn->auth_group, peer->auth))
427		return -1;
428
429	return 0;
430}
431
432
433int ibss_rsn_start(struct ibss_rsn *ibss_rsn, const u8 *addr)
434{
435	struct ibss_rsn_peer *peer;
436
437	if (ibss_rsn == NULL)
438		return -1;
439
440	if (ibss_rsn_get_peer(ibss_rsn, addr)) {
441		wpa_printf(MSG_DEBUG, "RSN: IBSS Authenticator and Supplicant "
442			   "for peer " MACSTR " already running",
443			   MAC2STR(addr));
444		return 0;
445	}
446
447	wpa_printf(MSG_DEBUG, "RSN: Starting IBSS Authenticator and "
448		   "Supplicant for peer " MACSTR, MAC2STR(addr));
449
450	peer = os_zalloc(sizeof(*peer));
451	if (peer == NULL)
452		return -1;
453
454	peer->ibss_rsn = ibss_rsn;
455	os_memcpy(peer->addr, addr, ETH_ALEN);
456
457	if (ibss_rsn_supp_init(peer, ibss_rsn->wpa_s->own_addr, ibss_rsn->psk)
458	    < 0) {
459		ibss_rsn_free(peer);
460		return -1;
461	}
462
463	if (ibss_rsn_auth_init(ibss_rsn, peer) < 0) {
464		ibss_rsn_free(peer);
465		return -1;
466	}
467
468	peer->next = ibss_rsn->peers;
469	ibss_rsn->peers = peer;
470
471	return 0;
472}
473
474
475void ibss_rsn_stop(struct ibss_rsn *ibss_rsn, const u8 *peermac)
476{
477	struct ibss_rsn_peer *peer, *prev;
478
479	if (ibss_rsn == NULL)
480		return;
481
482	if (peermac == NULL) {
483		/* remove all peers */
484		wpa_printf(MSG_DEBUG, "%s: Remove all peers", __func__);
485		peer = ibss_rsn->peers;
486		while (peer) {
487			prev = peer;
488			peer = peer->next;
489			ibss_rsn_free(prev);
490			ibss_rsn->peers = peer;
491		}
492	} else {
493		/* remove specific peer */
494		wpa_printf(MSG_DEBUG, "%s: Remove specific peer " MACSTR,
495			   __func__, MAC2STR(peermac));
496
497		for (prev = NULL, peer = ibss_rsn->peers; peer != NULL;
498		     prev = peer, peer = peer->next) {
499			if (os_memcmp(peermac, peer->addr, ETH_ALEN) == 0) {
500				if (prev == NULL)
501					ibss_rsn->peers = peer->next;
502				else
503					prev->next = peer->next;
504				ibss_rsn_free(peer);
505				wpa_printf(MSG_DEBUG, "%s: Successfully "
506					   "removed a specific peer",
507					   __func__);
508				break;
509			}
510		}
511	}
512}
513
514
515struct ibss_rsn * ibss_rsn_init(struct wpa_supplicant *wpa_s)
516{
517	struct ibss_rsn *ibss_rsn;
518
519	ibss_rsn = os_zalloc(sizeof(*ibss_rsn));
520	if (ibss_rsn == NULL)
521		return NULL;
522	ibss_rsn->wpa_s = wpa_s;
523
524	if (ibss_rsn_auth_init_group(ibss_rsn, wpa_s->own_addr) < 0) {
525		ibss_rsn_deinit(ibss_rsn);
526		return NULL;
527	}
528
529	return ibss_rsn;
530}
531
532
533void ibss_rsn_deinit(struct ibss_rsn *ibss_rsn)
534{
535	struct ibss_rsn_peer *peer, *prev;
536
537	if (ibss_rsn == NULL)
538		return;
539
540	peer = ibss_rsn->peers;
541	while (peer) {
542		prev = peer;
543		peer = peer->next;
544		ibss_rsn_free(prev);
545	}
546
547	wpa_deinit(ibss_rsn->auth_group);
548	os_free(ibss_rsn);
549
550}
551
552
553static int ibss_rsn_eapol_dst_supp(const u8 *buf, size_t len)
554{
555	const struct ieee802_1x_hdr *hdr;
556	const struct wpa_eapol_key *key;
557	u16 key_info;
558	size_t plen;
559
560	/* TODO: Support other EAPOL packets than just EAPOL-Key */
561
562	if (len < sizeof(*hdr) + sizeof(*key))
563		return -1;
564
565	hdr = (const struct ieee802_1x_hdr *) buf;
566	key = (const struct wpa_eapol_key *) (hdr + 1);
567	plen = be_to_host16(hdr->length);
568
569	if (hdr->version < EAPOL_VERSION) {
570		/* TODO: backwards compatibility */
571	}
572	if (hdr->type != IEEE802_1X_TYPE_EAPOL_KEY) {
573		wpa_printf(MSG_DEBUG, "RSN: EAPOL frame (type %u) discarded, "
574			"not a Key frame", hdr->type);
575		return -1;
576	}
577	if (plen > len - sizeof(*hdr) || plen < sizeof(*key)) {
578		wpa_printf(MSG_DEBUG, "RSN: EAPOL frame payload size %lu "
579			   "invalid (frame size %lu)",
580			   (unsigned long) plen, (unsigned long) len);
581		return -1;
582	}
583
584	if (key->type != EAPOL_KEY_TYPE_RSN) {
585		wpa_printf(MSG_DEBUG, "RSN: EAPOL-Key type (%d) unknown, "
586			   "discarded", key->type);
587		return -1;
588	}
589
590	key_info = WPA_GET_BE16(key->key_info);
591
592	return !!(key_info & WPA_KEY_INFO_ACK);
593}
594
595
596static int ibss_rsn_process_rx_eapol(struct ibss_rsn *ibss_rsn,
597				     struct ibss_rsn_peer *peer,
598				     const u8 *buf, size_t len)
599{
600	int supp;
601	u8 *tmp;
602
603	supp = ibss_rsn_eapol_dst_supp(buf, len);
604	if (supp < 0)
605		return -1;
606
607	tmp = os_malloc(len);
608	if (tmp == NULL)
609		return -1;
610	os_memcpy(tmp, buf, len);
611	if (supp) {
612		wpa_printf(MSG_DEBUG, "RSN: IBSS RX EAPOL for Supplicant");
613		wpa_sm_rx_eapol(peer->supp, peer->addr, tmp, len);
614	} else {
615		wpa_printf(MSG_DEBUG, "RSN: IBSS RX EAPOL for Authenticator");
616		wpa_receive(ibss_rsn->auth_group, peer->auth, tmp, len);
617	}
618	os_free(tmp);
619
620	return 1;
621}
622
623
624int ibss_rsn_rx_eapol(struct ibss_rsn *ibss_rsn, const u8 *src_addr,
625		      const u8 *buf, size_t len)
626{
627	struct ibss_rsn_peer *peer;
628
629	if (ibss_rsn == NULL)
630		return -1;
631
632	peer = ibss_rsn_get_peer(ibss_rsn, src_addr);
633	if (peer)
634		return ibss_rsn_process_rx_eapol(ibss_rsn, peer, buf, len);
635
636	if (ibss_rsn_eapol_dst_supp(buf, len) > 0) {
637		/*
638		 * Create new IBSS peer based on an EAPOL message from the peer
639		 * Authenticator.
640		 */
641		if (ibss_rsn_start(ibss_rsn, src_addr) < 0)
642			return -1;
643		return ibss_rsn_process_rx_eapol(ibss_rsn, ibss_rsn->peers,
644						 buf, len);
645	}
646
647	return 0;
648}
649
650
651void ibss_rsn_set_psk(struct ibss_rsn *ibss_rsn, const u8 *psk)
652{
653	if (ibss_rsn == NULL)
654		return;
655	os_memcpy(ibss_rsn->psk, psk, PMK_LEN);
656}
657