1 /*
2  * wpa_supplicant - IBSS RSN
3  * Copyright (c) 2009-2013, 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 "common/wpa_ctrl.h"
13 #include "utils/eloop.h"
14 #include "l2_packet/l2_packet.h"
15 #include "rsn_supp/wpa.h"
16 #include "rsn_supp/wpa_ie.h"
17 #include "ap/wpa_auth.h"
18 #include "wpa_supplicant_i.h"
19 #include "driver_i.h"
20 #include "common/ieee802_11_defs.h"
21 #include "ibss_rsn.h"
22 
23 
24 static void ibss_rsn_auth_timeout(void *eloop_ctx, void *timeout_ctx);
25 
26 
ibss_rsn_get_peer(struct ibss_rsn * ibss_rsn,const u8 * addr)27 static struct ibss_rsn_peer * ibss_rsn_get_peer(struct ibss_rsn *ibss_rsn,
28 						const u8 *addr)
29 {
30 	struct ibss_rsn_peer *peer;
31 
32 	for (peer = ibss_rsn->peers; peer; peer = peer->next)
33 		if (os_memcmp(addr, peer->addr, ETH_ALEN) == 0)
34 			break;
35 	return peer;
36 }
37 
38 
ibss_rsn_free(struct ibss_rsn_peer * peer)39 static void ibss_rsn_free(struct ibss_rsn_peer *peer)
40 {
41 	eloop_cancel_timeout(ibss_rsn_auth_timeout, peer, NULL);
42 	wpa_auth_sta_deinit(peer->auth);
43 	wpa_sm_deinit(peer->supp);
44 	os_free(peer);
45 }
46 
47 
supp_set_state(void * ctx,enum wpa_states state)48 static void supp_set_state(void *ctx, enum wpa_states state)
49 {
50 	struct ibss_rsn_peer *peer = ctx;
51 	peer->supp_state = state;
52 }
53 
54 
supp_get_state(void * ctx)55 static enum wpa_states supp_get_state(void *ctx)
56 {
57 	struct ibss_rsn_peer *peer = ctx;
58 	return peer->supp_state;
59 }
60 
61 
supp_ether_send(void * ctx,const u8 * dest,u16 proto,const u8 * buf,size_t len)62 static int supp_ether_send(void *ctx, const u8 *dest, u16 proto, const u8 *buf,
63 			   size_t len)
64 {
65 	struct ibss_rsn_peer *peer = ctx;
66 	struct wpa_supplicant *wpa_s = peer->ibss_rsn->wpa_s;
67 
68 	wpa_printf(MSG_DEBUG, "SUPP: %s(dest=" MACSTR " proto=0x%04x "
69 		   "len=%lu)",
70 		   __func__, MAC2STR(dest), proto, (unsigned long) len);
71 
72 	if (wpa_s->l2)
73 		return l2_packet_send(wpa_s->l2, dest, proto, buf, len);
74 
75 	return -1;
76 }
77 
78 
supp_alloc_eapol(void * ctx,u8 type,const void * data,u16 data_len,size_t * msg_len,void ** data_pos)79 static u8 * supp_alloc_eapol(void *ctx, u8 type, const void *data,
80 			     u16 data_len, size_t *msg_len, void **data_pos)
81 {
82 	struct ieee802_1x_hdr *hdr;
83 
84 	wpa_printf(MSG_DEBUG, "SUPP: %s(type=%d data_len=%d)",
85 		   __func__, type, data_len);
86 
87 	*msg_len = sizeof(*hdr) + data_len;
88 	hdr = os_malloc(*msg_len);
89 	if (hdr == NULL)
90 		return NULL;
91 
92 	hdr->version = 2;
93 	hdr->type = type;
94 	hdr->length = host_to_be16(data_len);
95 
96 	if (data)
97 		os_memcpy(hdr + 1, data, data_len);
98 	else
99 		os_memset(hdr + 1, 0, data_len);
100 
101 	if (data_pos)
102 		*data_pos = hdr + 1;
103 
104 	return (u8 *) hdr;
105 }
106 
107 
supp_get_beacon_ie(void * ctx)108 static int supp_get_beacon_ie(void *ctx)
109 {
110 	struct ibss_rsn_peer *peer = ctx;
111 
112 	wpa_printf(MSG_DEBUG, "SUPP: %s", __func__);
113 	/* TODO: get correct RSN IE */
114 	return wpa_sm_set_ap_rsn_ie(peer->supp,
115 				    (u8 *) "\x30\x14\x01\x00"
116 				    "\x00\x0f\xac\x04"
117 				    "\x01\x00\x00\x0f\xac\x04"
118 				    "\x01\x00\x00\x0f\xac\x02"
119 				    "\x00\x00", 22);
120 }
121 
122 
ibss_check_rsn_completed(struct ibss_rsn_peer * peer)123 static void ibss_check_rsn_completed(struct ibss_rsn_peer *peer)
124 {
125 	struct wpa_supplicant *wpa_s = peer->ibss_rsn->wpa_s;
126 
127 	if ((peer->authentication_status &
128 	     (IBSS_RSN_SET_PTK_SUPP | IBSS_RSN_SET_PTK_AUTH)) !=
129 	    (IBSS_RSN_SET_PTK_SUPP | IBSS_RSN_SET_PTK_AUTH))
130 		return;
131 	if (peer->authentication_status & IBSS_RSN_REPORTED_PTK)
132 		return;
133 	peer->authentication_status |= IBSS_RSN_REPORTED_PTK;
134 	wpa_msg(wpa_s, MSG_INFO, IBSS_RSN_COMPLETED MACSTR,
135 		MAC2STR(peer->addr));
136 }
137 
138 
supp_set_key(void * ctx,enum wpa_alg alg,const u8 * addr,int key_idx,int set_tx,const u8 * seq,size_t seq_len,const u8 * key,size_t key_len)139 static int supp_set_key(void *ctx, enum wpa_alg alg,
140 			const u8 *addr, int key_idx, int set_tx,
141 			const u8 *seq, size_t seq_len,
142 			const u8 *key, size_t key_len)
143 {
144 	struct ibss_rsn_peer *peer = ctx;
145 
146 	wpa_printf(MSG_DEBUG, "SUPP: %s(alg=%d addr=" MACSTR " key_idx=%d "
147 		   "set_tx=%d)",
148 		   __func__, alg, MAC2STR(addr), key_idx, set_tx);
149 	wpa_hexdump(MSG_DEBUG, "SUPP: set_key - seq", seq, seq_len);
150 	wpa_hexdump_key(MSG_DEBUG, "SUPP: set_key - key", key, key_len);
151 
152 	if (key_idx == 0) {
153 		peer->authentication_status |= IBSS_RSN_SET_PTK_SUPP;
154 		ibss_check_rsn_completed(peer);
155 		/*
156 		 * In IBSS RSN, the pairwise key from the 4-way handshake
157 		 * initiated by the peer with highest MAC address is used.
158 		 */
159 		if (os_memcmp(peer->ibss_rsn->wpa_s->own_addr, peer->addr,
160 			      ETH_ALEN) > 0) {
161 			wpa_printf(MSG_DEBUG, "SUPP: Do not use this PTK");
162 			return 0;
163 		}
164 	}
165 
166 	if (is_broadcast_ether_addr(addr))
167 		addr = peer->addr;
168 	return wpa_drv_set_key(peer->ibss_rsn->wpa_s, alg, addr, key_idx,
169 			       set_tx, seq, seq_len, key, key_len);
170 }
171 
172 
supp_get_network_ctx(void * ctx)173 static void * supp_get_network_ctx(void *ctx)
174 {
175 	struct ibss_rsn_peer *peer = ctx;
176 	return wpa_supplicant_get_ssid(peer->ibss_rsn->wpa_s);
177 }
178 
179 
supp_mlme_setprotection(void * ctx,const u8 * addr,int protection_type,int key_type)180 static int supp_mlme_setprotection(void *ctx, const u8 *addr,
181 				   int protection_type, int key_type)
182 {
183 	wpa_printf(MSG_DEBUG, "SUPP: %s(addr=" MACSTR " protection_type=%d "
184 		   "key_type=%d)",
185 		   __func__, MAC2STR(addr), protection_type, key_type);
186 	return 0;
187 }
188 
189 
supp_cancel_auth_timeout(void * ctx)190 static void supp_cancel_auth_timeout(void *ctx)
191 {
192 	wpa_printf(MSG_DEBUG, "SUPP: %s", __func__);
193 }
194 
195 
supp_deauthenticate(void * ctx,u16 reason_code)196 static void supp_deauthenticate(void * ctx, u16 reason_code)
197 {
198 	wpa_printf(MSG_DEBUG, "SUPP: %s (TODO)", __func__);
199 }
200 
201 
ibss_rsn_supp_init(struct ibss_rsn_peer * peer,const u8 * own_addr,const u8 * psk)202 static int ibss_rsn_supp_init(struct ibss_rsn_peer *peer, const u8 *own_addr,
203 			      const u8 *psk)
204 {
205 	struct wpa_sm_ctx *ctx = os_zalloc(sizeof(*ctx));
206 	if (ctx == NULL)
207 		return -1;
208 
209 	ctx->ctx = peer;
210 	ctx->msg_ctx = peer->ibss_rsn->wpa_s;
211 	ctx->set_state = supp_set_state;
212 	ctx->get_state = supp_get_state;
213 	ctx->ether_send = supp_ether_send;
214 	ctx->get_beacon_ie = supp_get_beacon_ie;
215 	ctx->alloc_eapol = supp_alloc_eapol;
216 	ctx->set_key = supp_set_key;
217 	ctx->get_network_ctx = supp_get_network_ctx;
218 	ctx->mlme_setprotection = supp_mlme_setprotection;
219 	ctx->cancel_auth_timeout = supp_cancel_auth_timeout;
220 	ctx->deauthenticate = supp_deauthenticate;
221 	peer->supp = wpa_sm_init(ctx);
222 	if (peer->supp == NULL) {
223 		wpa_printf(MSG_DEBUG, "SUPP: wpa_sm_init() failed");
224 		os_free(ctx);
225 		return -1;
226 	}
227 
228 	wpa_sm_set_own_addr(peer->supp, own_addr);
229 	wpa_sm_set_param(peer->supp, WPA_PARAM_RSN_ENABLED, 1);
230 	wpa_sm_set_param(peer->supp, WPA_PARAM_PROTO, WPA_PROTO_RSN);
231 	wpa_sm_set_param(peer->supp, WPA_PARAM_PAIRWISE, WPA_CIPHER_CCMP);
232 	wpa_sm_set_param(peer->supp, WPA_PARAM_GROUP, WPA_CIPHER_CCMP);
233 	wpa_sm_set_param(peer->supp, WPA_PARAM_KEY_MGMT, WPA_KEY_MGMT_PSK);
234 	wpa_sm_set_pmk(peer->supp, psk, PMK_LEN, NULL, NULL);
235 
236 	peer->supp_ie_len = sizeof(peer->supp_ie);
237 	if (wpa_sm_set_assoc_wpa_ie_default(peer->supp, peer->supp_ie,
238 					    &peer->supp_ie_len) < 0) {
239 		wpa_printf(MSG_DEBUG, "SUPP: wpa_sm_set_assoc_wpa_ie_default()"
240 			   " failed");
241 		return -1;
242 	}
243 
244 	wpa_sm_notify_assoc(peer->supp, peer->addr);
245 
246 	return 0;
247 }
248 
249 
auth_logger(void * ctx,const u8 * addr,logger_level level,const char * txt)250 static void auth_logger(void *ctx, const u8 *addr, logger_level level,
251 			const char *txt)
252 {
253 	if (addr)
254 		wpa_printf(MSG_DEBUG, "AUTH: " MACSTR " - %s",
255 			   MAC2STR(addr), txt);
256 	else
257 		wpa_printf(MSG_DEBUG, "AUTH: %s", txt);
258 }
259 
260 
auth_get_psk(void * ctx,const u8 * addr,const u8 * p2p_dev_addr,const u8 * prev_psk,size_t * psk_len,int * vlan_id)261 static const u8 * auth_get_psk(void *ctx, const u8 *addr,
262 			       const u8 *p2p_dev_addr, const u8 *prev_psk,
263 			       size_t *psk_len, int *vlan_id)
264 {
265 	struct ibss_rsn *ibss_rsn = ctx;
266 
267 	if (psk_len)
268 		*psk_len = PMK_LEN;
269 	if (vlan_id)
270 		*vlan_id = 0;
271 	wpa_printf(MSG_DEBUG, "AUTH: %s (addr=" MACSTR " prev_psk=%p)",
272 		   __func__, MAC2STR(addr), prev_psk);
273 	if (prev_psk)
274 		return NULL;
275 	return ibss_rsn->psk;
276 }
277 
278 
auth_send_eapol(void * ctx,const u8 * addr,const u8 * data,size_t data_len,int encrypt)279 static int auth_send_eapol(void *ctx, const u8 *addr, const u8 *data,
280 			   size_t data_len, int encrypt)
281 {
282 	struct ibss_rsn *ibss_rsn = ctx;
283 	struct wpa_supplicant *wpa_s = ibss_rsn->wpa_s;
284 
285 	wpa_printf(MSG_DEBUG, "AUTH: %s(addr=" MACSTR " data_len=%lu "
286 		   "encrypt=%d)",
287 		   __func__, MAC2STR(addr), (unsigned long) data_len, encrypt);
288 
289 	if (wpa_s->l2)
290 		return l2_packet_send(wpa_s->l2, addr, ETH_P_EAPOL, data,
291 				      data_len);
292 
293 	return -1;
294 }
295 
296 
auth_set_key(void * ctx,int vlan_id,enum wpa_alg alg,const u8 * addr,int idx,u8 * key,size_t key_len)297 static int auth_set_key(void *ctx, int vlan_id, enum wpa_alg alg,
298 			const u8 *addr, int idx, u8 *key, size_t key_len)
299 {
300 	struct ibss_rsn *ibss_rsn = ctx;
301 	u8 seq[6];
302 
303 	os_memset(seq, 0, sizeof(seq));
304 
305 	if (addr) {
306 		wpa_printf(MSG_DEBUG, "AUTH: %s(alg=%d addr=" MACSTR
307 			   " key_idx=%d)",
308 			   __func__, alg, MAC2STR(addr), idx);
309 	} else {
310 		wpa_printf(MSG_DEBUG, "AUTH: %s(alg=%d key_idx=%d)",
311 			   __func__, alg, idx);
312 	}
313 	wpa_hexdump_key(MSG_DEBUG, "AUTH: set_key - key", key, key_len);
314 
315 	if (idx == 0) {
316 		if (addr) {
317 			struct ibss_rsn_peer *peer;
318 			peer = ibss_rsn_get_peer(ibss_rsn, addr);
319 			if (peer) {
320 				peer->authentication_status |=
321 					IBSS_RSN_SET_PTK_AUTH;
322 				ibss_check_rsn_completed(peer);
323 			}
324 		}
325 		/*
326 		 * In IBSS RSN, the pairwise key from the 4-way handshake
327 		 * initiated by the peer with highest MAC address is used.
328 		 */
329 		if (addr == NULL ||
330 		    os_memcmp(ibss_rsn->wpa_s->own_addr, addr, ETH_ALEN) < 0) {
331 			wpa_printf(MSG_DEBUG, "AUTH: Do not use this PTK");
332 			return 0;
333 		}
334 	}
335 
336 	return wpa_drv_set_key(ibss_rsn->wpa_s, alg, addr, idx,
337 			       1, seq, 6, key, key_len);
338 }
339 
340 
ibss_rsn_disconnect(void * ctx,const u8 * addr,u16 reason)341 static void ibss_rsn_disconnect(void *ctx, const u8 *addr, u16 reason)
342 {
343 	struct ibss_rsn *ibss_rsn = ctx;
344 	wpa_drv_sta_deauth(ibss_rsn->wpa_s, addr, reason);
345 }
346 
347 
auth_for_each_sta(void * ctx,int (* cb)(struct wpa_state_machine * sm,void * ctx),void * cb_ctx)348 static int auth_for_each_sta(void *ctx, int (*cb)(struct wpa_state_machine *sm,
349 						  void *ctx),
350 			     void *cb_ctx)
351 {
352 	struct ibss_rsn *ibss_rsn = ctx;
353 	struct ibss_rsn_peer *peer;
354 
355 	wpa_printf(MSG_DEBUG, "AUTH: for_each_sta");
356 
357 	for (peer = ibss_rsn->peers; peer; peer = peer->next) {
358 		if (peer->auth && cb(peer->auth, cb_ctx))
359 			return 1;
360 	}
361 
362 	return 0;
363 }
364 
365 
ibss_set_sta_authorized(struct ibss_rsn * ibss_rsn,struct ibss_rsn_peer * peer,int authorized)366 static void ibss_set_sta_authorized(struct ibss_rsn *ibss_rsn,
367 				    struct ibss_rsn_peer *peer, int authorized)
368 {
369 	int res;
370 
371 	if (authorized) {
372 		res = wpa_drv_sta_set_flags(ibss_rsn->wpa_s, peer->addr,
373 					    WPA_STA_AUTHORIZED,
374 					    WPA_STA_AUTHORIZED, ~0);
375 		wpa_printf(MSG_DEBUG, "AUTH: " MACSTR " authorizing port",
376 			   MAC2STR(peer->addr));
377 	} else {
378 		res = wpa_drv_sta_set_flags(ibss_rsn->wpa_s, peer->addr,
379 					    0, 0, ~WPA_STA_AUTHORIZED);
380 		wpa_printf(MSG_DEBUG, "AUTH: " MACSTR " unauthorizing port",
381 			   MAC2STR(peer->addr));
382 	}
383 
384 	if (res && errno != ENOENT) {
385 		wpa_printf(MSG_DEBUG, "Could not set station " MACSTR " flags "
386 			   "for kernel driver (errno=%d)",
387 			   MAC2STR(peer->addr), errno);
388 	}
389 }
390 
391 
auth_set_eapol(void * ctx,const u8 * addr,wpa_eapol_variable var,int value)392 static void auth_set_eapol(void *ctx, const u8 *addr,
393 				       wpa_eapol_variable var, int value)
394 {
395 	struct ibss_rsn *ibss_rsn = ctx;
396 	struct ibss_rsn_peer *peer = ibss_rsn_get_peer(ibss_rsn, addr);
397 
398 	if (peer == NULL)
399 		return;
400 
401 	switch (var) {
402 	case WPA_EAPOL_authorized:
403 		ibss_set_sta_authorized(ibss_rsn, peer, value);
404 		break;
405 	default:
406 		/* do not handle any other event */
407 		wpa_printf(MSG_DEBUG, "AUTH: eapol event not handled %d", var);
408 		break;
409 	}
410 }
411 
412 
ibss_rsn_auth_init_group(struct ibss_rsn * ibss_rsn,const u8 * own_addr,struct wpa_ssid * ssid)413 static int ibss_rsn_auth_init_group(struct ibss_rsn *ibss_rsn,
414 				    const u8 *own_addr, struct wpa_ssid *ssid)
415 {
416 	struct wpa_auth_config conf;
417 	static const struct wpa_auth_callbacks cb = {
418 		.logger = auth_logger,
419 		.set_eapol = auth_set_eapol,
420 		.send_eapol = auth_send_eapol,
421 		.get_psk = auth_get_psk,
422 		.set_key = auth_set_key,
423 		.for_each_sta = auth_for_each_sta,
424 		.disconnect = ibss_rsn_disconnect,
425 	};
426 
427 	wpa_printf(MSG_DEBUG, "AUTH: Initializing group state machine");
428 
429 	os_memset(&conf, 0, sizeof(conf));
430 	conf.wpa = 2;
431 	conf.wpa_key_mgmt = WPA_KEY_MGMT_PSK;
432 	conf.wpa_pairwise = WPA_CIPHER_CCMP;
433 	conf.rsn_pairwise = WPA_CIPHER_CCMP;
434 	conf.wpa_group = WPA_CIPHER_CCMP;
435 	conf.eapol_version = 2;
436 	conf.wpa_group_rekey = ssid->group_rekey ? ssid->group_rekey : 600;
437 	conf.wpa_group_update_count = 4;
438 	conf.wpa_pairwise_update_count = 4;
439 
440 	ibss_rsn->auth_group = wpa_init(own_addr, &conf, &cb, ibss_rsn);
441 	if (ibss_rsn->auth_group == NULL) {
442 		wpa_printf(MSG_DEBUG, "AUTH: wpa_init() failed");
443 		return -1;
444 	}
445 
446 	wpa_init_keys(ibss_rsn->auth_group);
447 
448 	return 0;
449 }
450 
451 
ibss_rsn_auth_init(struct ibss_rsn * ibss_rsn,struct ibss_rsn_peer * peer)452 static int ibss_rsn_auth_init(struct ibss_rsn *ibss_rsn,
453 			      struct ibss_rsn_peer *peer)
454 {
455 	peer->auth = wpa_auth_sta_init(ibss_rsn->auth_group, peer->addr, NULL);
456 	if (peer->auth == NULL) {
457 		wpa_printf(MSG_DEBUG, "AUTH: wpa_auth_sta_init() failed");
458 		return -1;
459 	}
460 
461 	/* TODO: get peer RSN IE with Probe Request */
462 	if (wpa_validate_wpa_ie(ibss_rsn->auth_group, peer->auth, 0,
463 				(u8 *) "\x30\x14\x01\x00"
464 				"\x00\x0f\xac\x04"
465 				"\x01\x00\x00\x0f\xac\x04"
466 				"\x01\x00\x00\x0f\xac\x02"
467 				"\x00\x00", 22, NULL, 0, NULL, 0) !=
468 	    WPA_IE_OK) {
469 		wpa_printf(MSG_DEBUG, "AUTH: wpa_validate_wpa_ie() failed");
470 		return -1;
471 	}
472 
473 	if (wpa_auth_sm_event(peer->auth, WPA_ASSOC))
474 		return -1;
475 
476 	if (wpa_auth_sta_associated(ibss_rsn->auth_group, peer->auth))
477 		return -1;
478 
479 	return 0;
480 }
481 
482 
ibss_rsn_send_auth(struct ibss_rsn * ibss_rsn,const u8 * da,int seq)483 static int ibss_rsn_send_auth(struct ibss_rsn *ibss_rsn, const u8 *da, int seq)
484 {
485 	struct ieee80211_mgmt auth;
486 	const size_t auth_length = IEEE80211_HDRLEN + sizeof(auth.u.auth);
487 	struct wpa_supplicant *wpa_s = ibss_rsn->wpa_s;
488 
489 	if (wpa_s->driver->send_frame == NULL)
490 		return -1;
491 
492 	os_memset(&auth, 0, sizeof(auth));
493 
494 	auth.frame_control = IEEE80211_FC(WLAN_FC_TYPE_MGMT,
495 					  WLAN_FC_STYPE_AUTH);
496 	os_memcpy(auth.da, da, ETH_ALEN);
497 	os_memcpy(auth.sa, wpa_s->own_addr, ETH_ALEN);
498 	os_memcpy(auth.bssid, wpa_s->bssid, ETH_ALEN);
499 
500 	auth.u.auth.auth_alg = host_to_le16(WLAN_AUTH_OPEN);
501 	auth.u.auth.auth_transaction = host_to_le16(seq);
502 	auth.u.auth.status_code = host_to_le16(WLAN_STATUS_SUCCESS);
503 
504 	wpa_printf(MSG_DEBUG, "RSN: IBSS TX Auth frame (SEQ %d) to " MACSTR,
505 		   seq, MAC2STR(da));
506 
507 	return wpa_s->driver->send_frame(wpa_s->drv_priv, (u8 *) &auth,
508 					 auth_length, 0);
509 }
510 
511 
ibss_rsn_is_auth_started(struct ibss_rsn_peer * peer)512 static int ibss_rsn_is_auth_started(struct ibss_rsn_peer * peer)
513 {
514 	return peer->authentication_status &
515 	       (IBSS_RSN_AUTH_BY_US | IBSS_RSN_AUTH_EAPOL_BY_US);
516 }
517 
518 
519 static struct ibss_rsn_peer *
ibss_rsn_peer_init(struct ibss_rsn * ibss_rsn,const u8 * addr)520 ibss_rsn_peer_init(struct ibss_rsn *ibss_rsn, const u8 *addr)
521 {
522 	struct ibss_rsn_peer *peer;
523 	if (ibss_rsn == NULL)
524 		return NULL;
525 
526 	peer = ibss_rsn_get_peer(ibss_rsn, addr);
527 	if (peer) {
528 		wpa_printf(MSG_DEBUG, "RSN: IBSS Supplicant for peer "MACSTR
529 			   " already running", MAC2STR(addr));
530 		return peer;
531 	}
532 
533 	wpa_printf(MSG_DEBUG, "RSN: Starting IBSS Supplicant for peer "MACSTR,
534 		   MAC2STR(addr));
535 
536 	peer = os_zalloc(sizeof(*peer));
537 	if (peer == NULL) {
538 		wpa_printf(MSG_DEBUG, "RSN: Could not allocate memory.");
539 		return NULL;
540 	}
541 
542 	peer->ibss_rsn = ibss_rsn;
543 	os_memcpy(peer->addr, addr, ETH_ALEN);
544 	peer->authentication_status = IBSS_RSN_AUTH_NOT_AUTHENTICATED;
545 
546 	if (ibss_rsn_supp_init(peer, ibss_rsn->wpa_s->own_addr,
547 			       ibss_rsn->psk) < 0) {
548 		ibss_rsn_free(peer);
549 		return NULL;
550 	}
551 
552 	peer->next = ibss_rsn->peers;
553 	ibss_rsn->peers = peer;
554 
555 	return peer;
556 }
557 
558 
ibss_rsn_auth_timeout(void * eloop_ctx,void * timeout_ctx)559 static void ibss_rsn_auth_timeout(void *eloop_ctx, void *timeout_ctx)
560 {
561 	struct ibss_rsn_peer *peer = eloop_ctx;
562 
563 	/*
564 	 * Assume peer does not support Authentication exchange or the frame was
565 	 * lost somewhere - start EAPOL Authenticator.
566 	 */
567 	wpa_printf(MSG_DEBUG,
568 		   "RSN: Timeout on waiting Authentication frame response from "
569 		   MACSTR " - start authenticator", MAC2STR(peer->addr));
570 
571 	peer->authentication_status |= IBSS_RSN_AUTH_BY_US;
572 	ibss_rsn_auth_init(peer->ibss_rsn, peer);
573 }
574 
575 
ibss_rsn_start(struct ibss_rsn * ibss_rsn,const u8 * addr)576 int ibss_rsn_start(struct ibss_rsn *ibss_rsn, const u8 *addr)
577 {
578 	struct ibss_rsn_peer *peer;
579 	int res;
580 
581 	if (!ibss_rsn)
582 		return -1;
583 
584 	/* if the peer already exists, exit immediately */
585 	peer = ibss_rsn_get_peer(ibss_rsn, addr);
586 	if (peer)
587 		return 0;
588 
589 	peer = ibss_rsn_peer_init(ibss_rsn, addr);
590 	if (peer == NULL)
591 		return -1;
592 
593 	/* Open Authentication: send first Authentication frame */
594 	res = ibss_rsn_send_auth(ibss_rsn, addr, 1);
595 	if (res) {
596 		/*
597 		 * The driver may not support Authentication frame exchange in
598 		 * IBSS. Ignore authentication and go through EAPOL exchange.
599 		 */
600 		peer->authentication_status |= IBSS_RSN_AUTH_BY_US;
601 		return ibss_rsn_auth_init(ibss_rsn, peer);
602 	} else {
603 		os_get_reltime(&peer->own_auth_tx);
604 		eloop_register_timeout(1, 0, ibss_rsn_auth_timeout, peer, NULL);
605 	}
606 
607 	return 0;
608 }
609 
610 
ibss_rsn_peer_authenticated(struct ibss_rsn * ibss_rsn,struct ibss_rsn_peer * peer,int reason)611 static int ibss_rsn_peer_authenticated(struct ibss_rsn *ibss_rsn,
612 				       struct ibss_rsn_peer *peer, int reason)
613 {
614 	int already_started;
615 
616 	if (ibss_rsn == NULL || peer == NULL)
617 		return -1;
618 
619 	already_started = ibss_rsn_is_auth_started(peer);
620 	peer->authentication_status |= reason;
621 
622 	if (already_started) {
623 		wpa_printf(MSG_DEBUG, "RSN: IBSS Authenticator already "
624 			   "started for peer " MACSTR, MAC2STR(peer->addr));
625 		return 0;
626 	}
627 
628 	wpa_printf(MSG_DEBUG, "RSN: Starting IBSS Authenticator "
629 		   "for now-authenticated peer " MACSTR, MAC2STR(peer->addr));
630 
631 	return ibss_rsn_auth_init(ibss_rsn, peer);
632 }
633 
634 
ibss_rsn_stop(struct ibss_rsn * ibss_rsn,const u8 * peermac)635 void ibss_rsn_stop(struct ibss_rsn *ibss_rsn, const u8 *peermac)
636 {
637 	struct ibss_rsn_peer *peer, *prev;
638 
639 	if (ibss_rsn == NULL)
640 		return;
641 
642 	if (peermac == NULL) {
643 		/* remove all peers */
644 		wpa_printf(MSG_DEBUG, "%s: Remove all peers", __func__);
645 		peer = ibss_rsn->peers;
646 		while (peer) {
647 			prev = peer;
648 			peer = peer->next;
649 			ibss_rsn_free(prev);
650 			ibss_rsn->peers = peer;
651 		}
652 	} else {
653 		/* remove specific peer */
654 		wpa_printf(MSG_DEBUG, "%s: Remove specific peer " MACSTR,
655 			   __func__, MAC2STR(peermac));
656 
657 		for (prev = NULL, peer = ibss_rsn->peers; peer != NULL;
658 		     prev = peer, peer = peer->next) {
659 			if (os_memcmp(peermac, peer->addr, ETH_ALEN) == 0) {
660 				if (prev == NULL)
661 					ibss_rsn->peers = peer->next;
662 				else
663 					prev->next = peer->next;
664 				ibss_rsn_free(peer);
665 				wpa_printf(MSG_DEBUG, "%s: Successfully "
666 					   "removed a specific peer",
667 					   __func__);
668 				break;
669 			}
670 		}
671 	}
672 }
673 
674 
ibss_rsn_init(struct wpa_supplicant * wpa_s,struct wpa_ssid * ssid)675 struct ibss_rsn * ibss_rsn_init(struct wpa_supplicant *wpa_s,
676 				struct wpa_ssid *ssid)
677 {
678 	struct ibss_rsn *ibss_rsn;
679 
680 	ibss_rsn = os_zalloc(sizeof(*ibss_rsn));
681 	if (ibss_rsn == NULL)
682 		return NULL;
683 	ibss_rsn->wpa_s = wpa_s;
684 
685 	if (ibss_rsn_auth_init_group(ibss_rsn, wpa_s->own_addr, ssid) < 0) {
686 		ibss_rsn_deinit(ibss_rsn);
687 		return NULL;
688 	}
689 
690 	return ibss_rsn;
691 }
692 
693 
ibss_rsn_deinit(struct ibss_rsn * ibss_rsn)694 void ibss_rsn_deinit(struct ibss_rsn *ibss_rsn)
695 {
696 	struct ibss_rsn_peer *peer, *prev;
697 
698 	if (ibss_rsn == NULL)
699 		return;
700 
701 	peer = ibss_rsn->peers;
702 	while (peer) {
703 		prev = peer;
704 		peer = peer->next;
705 		ibss_rsn_free(prev);
706 	}
707 
708 	if (ibss_rsn->auth_group)
709 		wpa_deinit(ibss_rsn->auth_group);
710 	os_free(ibss_rsn);
711 
712 }
713 
714 
ibss_rsn_eapol_dst_supp(const u8 * buf,size_t len)715 static int ibss_rsn_eapol_dst_supp(const u8 *buf, size_t len)
716 {
717 	const struct ieee802_1x_hdr *hdr;
718 	const struct wpa_eapol_key *key;
719 	u16 key_info;
720 	size_t plen;
721 
722 	/* TODO: Support other EAPOL packets than just EAPOL-Key */
723 
724 	if (len < sizeof(*hdr) + sizeof(*key))
725 		return -1;
726 
727 	hdr = (const struct ieee802_1x_hdr *) buf;
728 	key = (const struct wpa_eapol_key *) (hdr + 1);
729 	plen = be_to_host16(hdr->length);
730 
731 	if (hdr->version < EAPOL_VERSION) {
732 		/* TODO: backwards compatibility */
733 	}
734 	if (hdr->type != IEEE802_1X_TYPE_EAPOL_KEY) {
735 		wpa_printf(MSG_DEBUG, "RSN: EAPOL frame (type %u) discarded, "
736 			"not a Key frame", hdr->type);
737 		return -1;
738 	}
739 	if (plen > len - sizeof(*hdr) || plen < sizeof(*key)) {
740 		wpa_printf(MSG_DEBUG, "RSN: EAPOL frame payload size %lu "
741 			   "invalid (frame size %lu)",
742 			   (unsigned long) plen, (unsigned long) len);
743 		return -1;
744 	}
745 
746 	if (key->type != EAPOL_KEY_TYPE_RSN) {
747 		wpa_printf(MSG_DEBUG, "RSN: EAPOL-Key type (%d) unknown, "
748 			   "discarded", key->type);
749 		return -1;
750 	}
751 
752 	key_info = WPA_GET_BE16(key->key_info);
753 
754 	return !!(key_info & WPA_KEY_INFO_ACK);
755 }
756 
757 
ibss_rsn_process_rx_eapol(struct ibss_rsn * ibss_rsn,struct ibss_rsn_peer * peer,const u8 * buf,size_t len)758 static int ibss_rsn_process_rx_eapol(struct ibss_rsn *ibss_rsn,
759 				     struct ibss_rsn_peer *peer,
760 				     const u8 *buf, size_t len)
761 {
762 	int supp;
763 	u8 *tmp;
764 
765 	supp = ibss_rsn_eapol_dst_supp(buf, len);
766 	if (supp < 0)
767 		return -1;
768 
769 	tmp = os_memdup(buf, len);
770 	if (tmp == NULL)
771 		return -1;
772 	if (supp) {
773 		peer->authentication_status |= IBSS_RSN_AUTH_EAPOL_BY_PEER;
774 		wpa_printf(MSG_DEBUG, "RSN: IBSS RX EAPOL for Supplicant from "
775 			   MACSTR, MAC2STR(peer->addr));
776 		wpa_sm_rx_eapol(peer->supp, peer->addr, tmp, len);
777 	} else {
778 		if (ibss_rsn_is_auth_started(peer) == 0) {
779 			wpa_printf(MSG_DEBUG, "RSN: IBSS EAPOL for "
780 				   "Authenticator dropped as " MACSTR " is not "
781 				   "authenticated", MAC2STR(peer->addr));
782 			os_free(tmp);
783 			return -1;
784 		}
785 
786 		wpa_printf(MSG_DEBUG, "RSN: IBSS RX EAPOL for Authenticator "
787 			   "from "MACSTR, MAC2STR(peer->addr));
788 		wpa_receive(ibss_rsn->auth_group, peer->auth, tmp, len);
789 	}
790 	os_free(tmp);
791 
792 	return 1;
793 }
794 
795 
ibss_rsn_rx_eapol(struct ibss_rsn * ibss_rsn,const u8 * src_addr,const u8 * buf,size_t len)796 int ibss_rsn_rx_eapol(struct ibss_rsn *ibss_rsn, const u8 *src_addr,
797 		      const u8 *buf, size_t len)
798 {
799 	struct ibss_rsn_peer *peer;
800 
801 	if (ibss_rsn == NULL)
802 		return -1;
803 
804 	peer = ibss_rsn_get_peer(ibss_rsn, src_addr);
805 	if (peer)
806 		return ibss_rsn_process_rx_eapol(ibss_rsn, peer, buf, len);
807 
808 	if (ibss_rsn_eapol_dst_supp(buf, len) > 0) {
809 		/*
810 		 * Create new IBSS peer based on an EAPOL message from the peer
811 		 * Authenticator.
812 		 */
813 		peer = ibss_rsn_peer_init(ibss_rsn, src_addr);
814 		if (peer == NULL)
815 			return -1;
816 
817 		/* assume the peer is authenticated already */
818 		wpa_printf(MSG_DEBUG, "RSN: IBSS Not using IBSS Auth for peer "
819 			   MACSTR, MAC2STR(src_addr));
820 		ibss_rsn_peer_authenticated(ibss_rsn, peer,
821 					    IBSS_RSN_AUTH_EAPOL_BY_US);
822 
823 		return ibss_rsn_process_rx_eapol(ibss_rsn, ibss_rsn->peers,
824 						 buf, len);
825 	}
826 
827 	return 0;
828 }
829 
ibss_rsn_set_psk(struct ibss_rsn * ibss_rsn,const u8 * psk)830 void ibss_rsn_set_psk(struct ibss_rsn *ibss_rsn, const u8 *psk)
831 {
832 	if (ibss_rsn == NULL)
833 		return;
834 	os_memcpy(ibss_rsn->psk, psk, PMK_LEN);
835 }
836 
837 
ibss_rsn_handle_auth_1_of_2(struct ibss_rsn * ibss_rsn,struct ibss_rsn_peer * peer,const u8 * addr)838 static void ibss_rsn_handle_auth_1_of_2(struct ibss_rsn *ibss_rsn,
839 					struct ibss_rsn_peer *peer,
840 					const u8* addr)
841 {
842 	wpa_printf(MSG_DEBUG, "RSN: IBSS RX Auth frame (SEQ 1) from " MACSTR,
843 		   MAC2STR(addr));
844 
845 	if (peer &&
846 	    peer->authentication_status & (IBSS_RSN_SET_PTK_SUPP |
847 					   IBSS_RSN_SET_PTK_AUTH)) {
848 		/* Clear the TK for this pair to allow recovery from the case
849 		 * where the peer STA has restarted and lost its key while we
850 		 * still have a pairwise key configured. */
851 		wpa_printf(MSG_DEBUG, "RSN: Clear pairwise key for peer "
852 			   MACSTR, MAC2STR(addr));
853 		wpa_drv_set_key(ibss_rsn->wpa_s, WPA_ALG_NONE, addr, 0, 0,
854 				NULL, 0, NULL, 0);
855 	}
856 
857 	if (peer &&
858 	    peer->authentication_status & IBSS_RSN_AUTH_EAPOL_BY_PEER) {
859 		if (peer->own_auth_tx.sec) {
860 			struct os_reltime now, diff;
861 			os_get_reltime(&now);
862 			os_reltime_sub(&now, &peer->own_auth_tx, &diff);
863 			if (diff.sec == 0 && diff.usec < 500000) {
864 				wpa_printf(MSG_DEBUG, "RSN: Skip IBSS reinit since only %u usec from own Auth frame TX",
865 					   (int) diff.usec);
866 				goto skip_reinit;
867 			}
868 		}
869 		/*
870 		 * A peer sent us an Authentication frame even though it already
871 		 * started an EAPOL session. We should reinit state machines
872 		 * here, but it's much more complicated than just deleting and
873 		 * recreating the state machine
874 		 */
875 		wpa_printf(MSG_DEBUG, "RSN: IBSS Reinitializing station "
876 			   MACSTR, MAC2STR(addr));
877 
878 		ibss_rsn_stop(ibss_rsn, addr);
879 		peer = NULL;
880 	}
881 
882 	if (!peer) {
883 		peer = ibss_rsn_peer_init(ibss_rsn, addr);
884 		if (!peer)
885 			return;
886 
887 		wpa_printf(MSG_DEBUG, "RSN: IBSS Auth started by peer " MACSTR,
888 			   MAC2STR(addr));
889 	}
890 
891 skip_reinit:
892 	/* reply with an Authentication frame now, before sending an EAPOL */
893 	ibss_rsn_send_auth(ibss_rsn, addr, 2);
894 	/* no need to start another AUTH challenge in the other way.. */
895 	ibss_rsn_peer_authenticated(ibss_rsn, peer, IBSS_RSN_AUTH_EAPOL_BY_US);
896 }
897 
898 
ibss_rsn_handle_auth(struct ibss_rsn * ibss_rsn,const u8 * auth_frame,size_t len)899 void ibss_rsn_handle_auth(struct ibss_rsn *ibss_rsn, const u8 *auth_frame,
900 			  size_t len)
901 {
902 	const struct ieee80211_mgmt *header;
903 	struct ibss_rsn_peer *peer;
904 	size_t auth_length;
905 
906 	header = (const struct ieee80211_mgmt *) auth_frame;
907 	auth_length = IEEE80211_HDRLEN + sizeof(header->u.auth);
908 
909 	if (ibss_rsn == NULL || len < auth_length)
910 		return;
911 
912 	if (le_to_host16(header->u.auth.auth_alg) != WLAN_AUTH_OPEN ||
913 	    le_to_host16(header->u.auth.status_code) != WLAN_STATUS_SUCCESS)
914 		return;
915 
916 	peer = ibss_rsn_get_peer(ibss_rsn, header->sa);
917 
918 	switch (le_to_host16(header->u.auth.auth_transaction)) {
919 	case 1:
920 		ibss_rsn_handle_auth_1_of_2(ibss_rsn, peer, header->sa);
921 		break;
922 	case 2:
923 		wpa_printf(MSG_DEBUG, "RSN: IBSS RX Auth frame (SEQ 2) from "
924 			   MACSTR, MAC2STR(header->sa));
925 		if (!peer) {
926 			wpa_printf(MSG_DEBUG, "RSN: Received Auth seq 2 from "
927 				   "unknown STA " MACSTR, MAC2STR(header->sa));
928 			break;
929 		}
930 
931 		/* authentication has been completed */
932 		eloop_cancel_timeout(ibss_rsn_auth_timeout, peer, NULL);
933 		wpa_printf(MSG_DEBUG, "RSN: IBSS Auth completed with " MACSTR,
934 			   MAC2STR(header->sa));
935 		ibss_rsn_peer_authenticated(ibss_rsn, peer,
936 					    IBSS_RSN_AUTH_BY_US);
937 		break;
938 	}
939 }
940