1/*
2 * wpa_supplicant - IBSS RSN
3 * Copyright (c) 2009, Jouni Malinen <j@w1.fi>
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 "l2_packet/l2_packet.h"
19#include "rsn_supp/wpa.h"
20#include "rsn_supp/wpa_ie.h"
21#include "ap/wpa_auth.h"
22#include "wpa_supplicant_i.h"
23#include "driver_i.h"
24#include "ibss_rsn.h"
25
26
27static void ibss_rsn_free(struct ibss_rsn_peer *peer)
28{
29	wpa_auth_sta_deinit(peer->auth);
30	wpa_sm_deinit(peer->supp);
31	os_free(peer);
32}
33
34
35static void supp_set_state(void *ctx, enum wpa_states state)
36{
37	struct ibss_rsn_peer *peer = ctx;
38	peer->supp_state = state;
39}
40
41
42static int supp_ether_send(void *ctx, const u8 *dest, u16 proto, const u8 *buf,
43			   size_t len)
44{
45	struct ibss_rsn_peer *peer = ctx;
46	struct wpa_supplicant *wpa_s = peer->ibss_rsn->wpa_s;
47
48	wpa_printf(MSG_DEBUG, "SUPP: %s(dest=" MACSTR " proto=0x%04x "
49		   "len=%lu)",
50		   __func__, MAC2STR(dest), proto, (unsigned long) len);
51
52	if (wpa_s->l2)
53		return l2_packet_send(wpa_s->l2, dest, proto, buf, len);
54
55	return wpa_drv_send_eapol(wpa_s, dest, proto, buf, len);
56}
57
58
59static u8 * supp_alloc_eapol(void *ctx, u8 type, const void *data,
60			     u16 data_len, size_t *msg_len, void **data_pos)
61{
62	struct ieee802_1x_hdr *hdr;
63
64	wpa_printf(MSG_DEBUG, "SUPP: %s(type=%d data_len=%d)",
65		   __func__, type, data_len);
66
67	*msg_len = sizeof(*hdr) + data_len;
68	hdr = os_malloc(*msg_len);
69	if (hdr == NULL)
70		return NULL;
71
72	hdr->version = 2;
73	hdr->type = type;
74	hdr->length = host_to_be16(data_len);
75
76	if (data)
77		os_memcpy(hdr + 1, data, data_len);
78	else
79		os_memset(hdr + 1, 0, data_len);
80
81	if (data_pos)
82		*data_pos = hdr + 1;
83
84	return (u8 *) hdr;
85}
86
87
88static int supp_get_beacon_ie(void *ctx)
89{
90	struct ibss_rsn_peer *peer = ctx;
91
92	wpa_printf(MSG_DEBUG, "SUPP: %s", __func__);
93	/* TODO: get correct RSN IE */
94	return wpa_sm_set_ap_rsn_ie(peer->supp,
95				    (u8 *) "\x30\x14\x01\x00"
96				    "\x00\x0f\xac\x04"
97				    "\x01\x00\x00\x0f\xac\x04"
98				    "\x01\x00\x00\x0f\xac\x02"
99				    "\x00\x00", 22);
100}
101
102
103static int supp_set_key(void *ctx, enum wpa_alg alg,
104			const u8 *addr, int key_idx, int set_tx,
105			const u8 *seq, size_t seq_len,
106			const u8 *key, size_t key_len)
107{
108	struct ibss_rsn_peer *peer = ctx;
109
110	wpa_printf(MSG_DEBUG, "SUPP: %s(alg=%d addr=" MACSTR " key_idx=%d "
111		   "set_tx=%d)",
112		   __func__, alg, MAC2STR(addr), key_idx, set_tx);
113	wpa_hexdump(MSG_DEBUG, "SUPP: set_key - seq", seq, seq_len);
114	wpa_hexdump_key(MSG_DEBUG, "SUPP: set_key - key", key, key_len);
115
116	if (key_idx == 0) {
117		/*
118		 * In IBSS RSN, the pairwise key from the 4-way handshake
119		 * initiated by the peer with highest MAC address is used.
120		 */
121		if (os_memcmp(peer->ibss_rsn->wpa_s->own_addr, peer->addr,
122			      ETH_ALEN) > 0) {
123			wpa_printf(MSG_DEBUG, "SUPP: Do not use this PTK");
124			return 0;
125		}
126	}
127
128	return wpa_drv_set_key(peer->ibss_rsn->wpa_s, alg, addr, key_idx,
129			       set_tx, seq, seq_len, key, key_len);
130}
131
132
133static void * supp_get_network_ctx(void *ctx)
134{
135	struct ibss_rsn_peer *peer = ctx;
136	return wpa_supplicant_get_ssid(peer->ibss_rsn->wpa_s);
137}
138
139
140static int supp_mlme_setprotection(void *ctx, const u8 *addr,
141				   int protection_type, int key_type)
142{
143	wpa_printf(MSG_DEBUG, "SUPP: %s(addr=" MACSTR " protection_type=%d "
144		   "key_type=%d)",
145		   __func__, MAC2STR(addr), protection_type, key_type);
146	return 0;
147}
148
149
150static void supp_cancel_auth_timeout(void *ctx)
151{
152	wpa_printf(MSG_DEBUG, "SUPP: %s", __func__);
153}
154
155
156int ibss_rsn_supp_init(struct ibss_rsn_peer *peer, const u8 *own_addr,
157		       const u8 *psk)
158{
159	struct wpa_sm_ctx *ctx = os_zalloc(sizeof(*ctx));
160	if (ctx == NULL)
161		return -1;
162
163	ctx->ctx = peer;
164	ctx->msg_ctx = peer->ibss_rsn->wpa_s;
165	ctx->set_state = supp_set_state;
166	ctx->ether_send = supp_ether_send;
167	ctx->get_beacon_ie = supp_get_beacon_ie;
168	ctx->alloc_eapol = supp_alloc_eapol;
169	ctx->set_key = supp_set_key;
170	ctx->get_network_ctx = supp_get_network_ctx;
171	ctx->mlme_setprotection = supp_mlme_setprotection;
172	ctx->cancel_auth_timeout = supp_cancel_auth_timeout;
173	peer->supp = wpa_sm_init(ctx);
174	if (peer->supp == NULL) {
175		wpa_printf(MSG_DEBUG, "SUPP: wpa_sm_init() failed");
176		return -1;
177	}
178
179	wpa_sm_set_own_addr(peer->supp, own_addr);
180	wpa_sm_set_param(peer->supp, WPA_PARAM_RSN_ENABLED, 1);
181	wpa_sm_set_param(peer->supp, WPA_PARAM_PROTO, WPA_PROTO_RSN);
182	wpa_sm_set_param(peer->supp, WPA_PARAM_PAIRWISE, WPA_CIPHER_CCMP);
183	wpa_sm_set_param(peer->supp, WPA_PARAM_GROUP, WPA_CIPHER_CCMP);
184	wpa_sm_set_param(peer->supp, WPA_PARAM_KEY_MGMT, WPA_KEY_MGMT_PSK);
185	wpa_sm_set_pmk(peer->supp, psk, PMK_LEN);
186
187	peer->supp_ie_len = sizeof(peer->supp_ie);
188	if (wpa_sm_set_assoc_wpa_ie_default(peer->supp, peer->supp_ie,
189					    &peer->supp_ie_len) < 0) {
190		wpa_printf(MSG_DEBUG, "SUPP: wpa_sm_set_assoc_wpa_ie_default()"
191			   " failed");
192		return -1;
193	}
194
195	wpa_sm_notify_assoc(peer->supp, peer->addr);
196
197	return 0;
198}
199
200
201static void auth_logger(void *ctx, const u8 *addr, logger_level level,
202			const char *txt)
203{
204	if (addr)
205		wpa_printf(MSG_DEBUG, "AUTH: " MACSTR " - %s",
206			   MAC2STR(addr), txt);
207	else
208		wpa_printf(MSG_DEBUG, "AUTH: %s", txt);
209}
210
211
212static const u8 * auth_get_psk(void *ctx, const u8 *addr, const u8 *prev_psk)
213{
214	struct ibss_rsn *ibss_rsn = ctx;
215	wpa_printf(MSG_DEBUG, "AUTH: %s (addr=" MACSTR " prev_psk=%p)",
216		   __func__, MAC2STR(addr), prev_psk);
217	if (prev_psk)
218		return NULL;
219	return ibss_rsn->psk;
220}
221
222
223static int auth_send_eapol(void *ctx, const u8 *addr, const u8 *data,
224			   size_t data_len, int encrypt)
225{
226	struct ibss_rsn *ibss_rsn = ctx;
227	struct wpa_supplicant *wpa_s = ibss_rsn->wpa_s;
228
229	wpa_printf(MSG_DEBUG, "AUTH: %s(addr=" MACSTR " data_len=%lu "
230		   "encrypt=%d)",
231		   __func__, MAC2STR(addr), (unsigned long) data_len, encrypt);
232
233	if (wpa_s->l2)
234		return l2_packet_send(wpa_s->l2, addr, ETH_P_EAPOL, data,
235				      data_len);
236
237	return wpa_drv_send_eapol(wpa_s, addr, ETH_P_EAPOL, data, data_len);
238}
239
240
241static int auth_set_key(void *ctx, int vlan_id, enum wpa_alg alg,
242			const u8 *addr, int idx, u8 *key, size_t key_len)
243{
244	struct ibss_rsn *ibss_rsn = ctx;
245	u8 seq[6];
246
247	os_memset(seq, 0, sizeof(seq));
248
249	if (addr) {
250		wpa_printf(MSG_DEBUG, "AUTH: %s(alg=%d addr=" MACSTR
251			   " key_idx=%d)",
252			   __func__, alg, MAC2STR(addr), idx);
253	} else {
254		wpa_printf(MSG_DEBUG, "AUTH: %s(alg=%d key_idx=%d)",
255			   __func__, alg, idx);
256	}
257	wpa_hexdump_key(MSG_DEBUG, "AUTH: set_key - key", key, key_len);
258
259	if (idx == 0) {
260		/*
261		 * In IBSS RSN, the pairwise key from the 4-way handshake
262		 * initiated by the peer with highest MAC address is used.
263		 */
264		if (addr == NULL ||
265		    os_memcmp(ibss_rsn->wpa_s->own_addr, addr, ETH_ALEN) < 0) {
266			wpa_printf(MSG_DEBUG, "AUTH: Do not use this PTK");
267			return 0;
268		}
269	}
270
271	return wpa_drv_set_key(ibss_rsn->wpa_s, alg, addr, idx,
272			       1, seq, 6, key, key_len);
273}
274
275
276static int ibss_rsn_auth_init_group(struct ibss_rsn *ibss_rsn,
277				    const u8 *own_addr)
278{
279	struct wpa_auth_config conf;
280	struct wpa_auth_callbacks cb;
281
282	wpa_printf(MSG_DEBUG, "AUTH: Initializing group state machine");
283
284	os_memset(&conf, 0, sizeof(conf));
285	conf.wpa = 2;
286	conf.wpa_key_mgmt = WPA_KEY_MGMT_PSK;
287	conf.wpa_pairwise = WPA_CIPHER_CCMP;
288	conf.rsn_pairwise = WPA_CIPHER_CCMP;
289	conf.wpa_group = WPA_CIPHER_CCMP;
290	conf.eapol_version = 2;
291
292	os_memset(&cb, 0, sizeof(cb));
293	cb.ctx = ibss_rsn;
294	cb.logger = auth_logger;
295	cb.send_eapol = auth_send_eapol;
296	cb.get_psk = auth_get_psk;
297	cb.set_key = auth_set_key;
298
299	ibss_rsn->auth_group = wpa_init(own_addr, &conf, &cb);
300	if (ibss_rsn->auth_group == NULL) {
301		wpa_printf(MSG_DEBUG, "AUTH: wpa_init() failed");
302		return -1;
303	}
304
305	return 0;
306}
307
308
309static int ibss_rsn_auth_init(struct ibss_rsn *ibss_rsn,
310			      struct ibss_rsn_peer *peer)
311{
312	peer->auth = wpa_auth_sta_init(ibss_rsn->auth_group, peer->addr);
313	if (peer->auth == NULL) {
314		wpa_printf(MSG_DEBUG, "AUTH: wpa_auth_sta_init() failed");
315		return -1;
316	}
317
318	/* TODO: get peer RSN IE with Probe Request */
319	if (wpa_validate_wpa_ie(ibss_rsn->auth_group, peer->auth,
320				(u8 *) "\x30\x14\x01\x00"
321				"\x00\x0f\xac\x04"
322				"\x01\x00\x00\x0f\xac\x04"
323				"\x01\x00\x00\x0f\xac\x02"
324				"\x00\x00", 22, NULL, 0) !=
325	    WPA_IE_OK) {
326		wpa_printf(MSG_DEBUG, "AUTH: wpa_validate_wpa_ie() failed");
327		return -1;
328	}
329
330	if (wpa_auth_sm_event(peer->auth, WPA_ASSOC))
331		return -1;
332
333	if (wpa_auth_sta_associated(ibss_rsn->auth_group, peer->auth))
334		return -1;
335
336	return 0;
337}
338
339
340int ibss_rsn_start(struct ibss_rsn *ibss_rsn, const u8 *addr)
341{
342	struct ibss_rsn_peer *peer;
343
344	wpa_printf(MSG_DEBUG, "RSN: Starting IBSS Authenticator and "
345		   "Supplicant for peer " MACSTR, MAC2STR(addr));
346
347	peer = os_zalloc(sizeof(*peer));
348	if (peer == NULL)
349		return -1;
350
351	peer->ibss_rsn = ibss_rsn;
352	os_memcpy(peer->addr, addr, ETH_ALEN);
353
354	if (ibss_rsn_supp_init(peer, ibss_rsn->wpa_s->own_addr, ibss_rsn->psk)
355	    < 0) {
356		ibss_rsn_free(peer);
357		return -1;
358	}
359
360	if (ibss_rsn_auth_init(ibss_rsn, peer) < 0) {
361		ibss_rsn_free(peer);
362		return -1;
363	}
364
365	peer->next = ibss_rsn->peers;
366	ibss_rsn->peers = peer;
367
368	return 0;
369}
370
371
372struct ibss_rsn * ibss_rsn_init(struct wpa_supplicant *wpa_s)
373{
374	struct ibss_rsn *ibss_rsn;
375
376	ibss_rsn = os_zalloc(sizeof(*ibss_rsn));
377	if (ibss_rsn == NULL)
378		return NULL;
379	ibss_rsn->wpa_s = wpa_s;
380
381	if (ibss_rsn_auth_init_group(ibss_rsn, wpa_s->own_addr) < 0) {
382		ibss_rsn_deinit(ibss_rsn);
383		return NULL;
384	}
385
386	return ibss_rsn;
387}
388
389
390void ibss_rsn_deinit(struct ibss_rsn *ibss_rsn)
391{
392	struct ibss_rsn_peer *peer, *prev;
393
394	if (ibss_rsn == NULL)
395		return;
396
397	peer = ibss_rsn->peers;
398	while (peer) {
399		prev = peer;
400		peer = peer->next;
401		ibss_rsn_free(prev);
402	}
403
404	wpa_deinit(ibss_rsn->auth_group);
405	os_free(ibss_rsn);
406
407}
408
409
410static int ibss_rsn_eapol_dst_supp(const u8 *buf, size_t len)
411{
412	const struct ieee802_1x_hdr *hdr;
413	const struct wpa_eapol_key *key;
414	u16 key_info;
415	size_t plen;
416
417	/* TODO: Support other EAPOL packets than just EAPOL-Key */
418
419	if (len < sizeof(*hdr) + sizeof(*key))
420		return -1;
421
422	hdr = (const struct ieee802_1x_hdr *) buf;
423	key = (const struct wpa_eapol_key *) (hdr + 1);
424	plen = be_to_host16(hdr->length);
425
426	if (hdr->version < EAPOL_VERSION) {
427		/* TODO: backwards compatibility */
428	}
429	if (hdr->type != IEEE802_1X_TYPE_EAPOL_KEY) {
430		wpa_printf(MSG_DEBUG, "RSN: EAPOL frame (type %u) discarded, "
431			"not a Key frame", hdr->type);
432		return -1;
433	}
434	if (plen > len - sizeof(*hdr) || plen < sizeof(*key)) {
435		wpa_printf(MSG_DEBUG, "RSN: EAPOL frame payload size %lu "
436			   "invalid (frame size %lu)",
437			   (unsigned long) plen, (unsigned long) len);
438		return -1;
439	}
440
441	if (key->type != EAPOL_KEY_TYPE_RSN) {
442		wpa_printf(MSG_DEBUG, "RSN: EAPOL-Key type (%d) unknown, "
443			   "discarded", key->type);
444		return -1;
445	}
446
447	key_info = WPA_GET_BE16(key->key_info);
448
449	return !!(key_info & WPA_KEY_INFO_ACK);
450}
451
452
453static int ibss_rsn_process_rx_eapol(struct ibss_rsn *ibss_rsn,
454				     struct ibss_rsn_peer *peer,
455				     const u8 *buf, size_t len)
456{
457	int supp;
458	u8 *tmp;
459
460	supp = ibss_rsn_eapol_dst_supp(buf, len);
461	if (supp < 0)
462		return -1;
463
464	tmp = os_malloc(len);
465	if (tmp == NULL)
466		return -1;
467	os_memcpy(tmp, buf, len);
468	if (supp) {
469		wpa_printf(MSG_DEBUG, "RSN: IBSS RX EAPOL for Supplicant");
470		wpa_sm_rx_eapol(peer->supp, peer->addr, tmp, len);
471	} else {
472		wpa_printf(MSG_DEBUG, "RSN: IBSS RX EAPOL for Authenticator");
473		wpa_receive(ibss_rsn->auth_group, peer->auth, tmp, len);
474	}
475	os_free(tmp);
476
477	return 1;
478}
479
480
481int ibss_rsn_rx_eapol(struct ibss_rsn *ibss_rsn, const u8 *src_addr,
482		      const u8 *buf, size_t len)
483{
484	struct ibss_rsn_peer *peer;
485
486	for (peer = ibss_rsn->peers; peer; peer = peer->next) {
487		if (os_memcmp(src_addr, peer->addr, ETH_ALEN) == 0)
488			return ibss_rsn_process_rx_eapol(ibss_rsn, peer,
489							 buf, len);
490	}
491
492	if (ibss_rsn_eapol_dst_supp(buf, len) > 0) {
493		/*
494		 * Create new IBSS peer based on an EAPOL message from the peer
495		 * Authenticator.
496		 */
497		if (ibss_rsn_start(ibss_rsn, src_addr) < 0)
498			return -1;
499		return ibss_rsn_process_rx_eapol(ibss_rsn, ibss_rsn->peers,
500						 buf, len);
501	}
502
503	return 0;
504}
505
506
507void ibss_rsn_set_psk(struct ibss_rsn *ibss_rsn, const u8 *psk)
508{
509	os_memcpy(ibss_rsn->psk, psk, PMK_LEN);
510}
511