xref: /freebsd/contrib/wpa/wpa_supplicant/sme.c (revision aa0a1e58)
1 /*
2  * wpa_supplicant - SME
3  * Copyright (c) 2009-2010, 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 "common/ieee802_11_defs.h"
19 #include "common/ieee802_11_common.h"
20 #include "eapol_supp/eapol_supp_sm.h"
21 #include "common/wpa_common.h"
22 #include "rsn_supp/wpa.h"
23 #include "rsn_supp/pmksa_cache.h"
24 #include "config.h"
25 #include "wpa_supplicant_i.h"
26 #include "driver_i.h"
27 #include "wpas_glue.h"
28 #include "wps_supplicant.h"
29 #include "notify.h"
30 #include "blacklist.h"
31 #include "bss.h"
32 #include "scan.h"
33 #include "sme.h"
34 
35 void sme_authenticate(struct wpa_supplicant *wpa_s,
36 		      struct wpa_bss *bss, struct wpa_ssid *ssid)
37 {
38 	struct wpa_driver_auth_params params;
39 	struct wpa_ssid *old_ssid;
40 #ifdef CONFIG_IEEE80211R
41 	const u8 *ie;
42 #endif /* CONFIG_IEEE80211R */
43 #ifdef CONFIG_IEEE80211R
44 	const u8 *md = NULL;
45 #endif /* CONFIG_IEEE80211R */
46 	int i, bssid_changed;
47 
48 	if (bss == NULL) {
49 		wpa_printf(MSG_ERROR, "SME: No scan result available for the "
50 			   "network");
51 		return;
52 	}
53 
54 	wpa_s->current_bss = bss;
55 
56 	os_memset(&params, 0, sizeof(params));
57 	wpa_s->reassociate = 0;
58 
59 	params.freq = bss->freq;
60 	params.bssid = bss->bssid;
61 	params.ssid = bss->ssid;
62 	params.ssid_len = bss->ssid_len;
63 
64 	if (wpa_s->sme.ssid_len != params.ssid_len ||
65 	    os_memcmp(wpa_s->sme.ssid, params.ssid, params.ssid_len) != 0)
66 		wpa_s->sme.prev_bssid_set = 0;
67 
68 	wpa_s->sme.freq = params.freq;
69 	os_memcpy(wpa_s->sme.ssid, params.ssid, params.ssid_len);
70 	wpa_s->sme.ssid_len = params.ssid_len;
71 
72 	params.auth_alg = WPA_AUTH_ALG_OPEN;
73 #ifdef IEEE8021X_EAPOL
74 	if (ssid->key_mgmt & WPA_KEY_MGMT_IEEE8021X_NO_WPA) {
75 		if (ssid->leap) {
76 			if (ssid->non_leap == 0)
77 				params.auth_alg = WPA_AUTH_ALG_LEAP;
78 			else
79 				params.auth_alg |= WPA_AUTH_ALG_LEAP;
80 		}
81 	}
82 #endif /* IEEE8021X_EAPOL */
83 	wpa_printf(MSG_DEBUG, "Automatic auth_alg selection: 0x%x",
84 		   params.auth_alg);
85 	if (ssid->auth_alg) {
86 		params.auth_alg = ssid->auth_alg;
87 		wpa_printf(MSG_DEBUG, "Overriding auth_alg selection: 0x%x",
88 			   params.auth_alg);
89 	}
90 
91 	for (i = 0; i < NUM_WEP_KEYS; i++) {
92 		if (ssid->wep_key_len[i])
93 			params.wep_key[i] = ssid->wep_key[i];
94 		params.wep_key_len[i] = ssid->wep_key_len[i];
95 	}
96 	params.wep_tx_keyidx = ssid->wep_tx_keyidx;
97 
98 	bssid_changed = !is_zero_ether_addr(wpa_s->bssid);
99 	os_memset(wpa_s->bssid, 0, ETH_ALEN);
100 	os_memcpy(wpa_s->pending_bssid, bss->bssid, ETH_ALEN);
101 	if (bssid_changed)
102 		wpas_notify_bssid_changed(wpa_s);
103 
104 	if ((wpa_bss_get_vendor_ie(bss, WPA_IE_VENDOR_TYPE) ||
105 	     wpa_bss_get_ie(bss, WLAN_EID_RSN)) &&
106 	    (ssid->key_mgmt & (WPA_KEY_MGMT_IEEE8021X | WPA_KEY_MGMT_PSK |
107 			       WPA_KEY_MGMT_FT_IEEE8021X |
108 			       WPA_KEY_MGMT_FT_PSK |
109 			       WPA_KEY_MGMT_IEEE8021X_SHA256 |
110 			       WPA_KEY_MGMT_PSK_SHA256))) {
111 		int try_opportunistic;
112 		try_opportunistic = ssid->proactive_key_caching &&
113 			(ssid->proto & WPA_PROTO_RSN);
114 		if (pmksa_cache_set_current(wpa_s->wpa, NULL, bss->bssid,
115 					    wpa_s->current_ssid,
116 					    try_opportunistic) == 0)
117 			eapol_sm_notify_pmkid_attempt(wpa_s->eapol, 1);
118 		wpa_s->sme.assoc_req_ie_len = sizeof(wpa_s->sme.assoc_req_ie);
119 		if (wpa_supplicant_set_suites(wpa_s, bss, ssid,
120 					      wpa_s->sme.assoc_req_ie,
121 					      &wpa_s->sme.assoc_req_ie_len)) {
122 			wpa_printf(MSG_WARNING, "SME: Failed to set WPA key "
123 				   "management and encryption suites");
124 			return;
125 		}
126 	} else if (ssid->key_mgmt &
127 		   (WPA_KEY_MGMT_PSK | WPA_KEY_MGMT_IEEE8021X |
128 		    WPA_KEY_MGMT_WPA_NONE | WPA_KEY_MGMT_FT_PSK |
129 		    WPA_KEY_MGMT_FT_IEEE8021X | WPA_KEY_MGMT_PSK_SHA256 |
130 		    WPA_KEY_MGMT_IEEE8021X_SHA256)) {
131 		wpa_s->sme.assoc_req_ie_len = sizeof(wpa_s->sme.assoc_req_ie);
132 		if (wpa_supplicant_set_suites(wpa_s, NULL, ssid,
133 					      wpa_s->sme.assoc_req_ie,
134 					      &wpa_s->sme.assoc_req_ie_len)) {
135 			wpa_printf(MSG_WARNING, "SME: Failed to set WPA key "
136 				   "management and encryption suites (no scan "
137 				   "results)");
138 			return;
139 		}
140 #ifdef CONFIG_WPS
141 	} else if (ssid->key_mgmt & WPA_KEY_MGMT_WPS) {
142 		struct wpabuf *wps_ie;
143 		wps_ie = wps_build_assoc_req_ie(wpas_wps_get_req_type(ssid));
144 		if (wps_ie && wpabuf_len(wps_ie) <=
145 		    sizeof(wpa_s->sme.assoc_req_ie)) {
146 			wpa_s->sme.assoc_req_ie_len = wpabuf_len(wps_ie);
147 			os_memcpy(wpa_s->sme.assoc_req_ie, wpabuf_head(wps_ie),
148 				  wpa_s->sme.assoc_req_ie_len);
149 		} else
150 			wpa_s->sme.assoc_req_ie_len = 0;
151 		wpabuf_free(wps_ie);
152 		wpa_supplicant_set_non_wpa_policy(wpa_s, ssid);
153 #endif /* CONFIG_WPS */
154 	} else {
155 		wpa_supplicant_set_non_wpa_policy(wpa_s, ssid);
156 		wpa_s->sme.assoc_req_ie_len = 0;
157 	}
158 
159 #ifdef CONFIG_IEEE80211R
160 	ie = wpa_bss_get_ie(bss, WLAN_EID_MOBILITY_DOMAIN);
161 	if (ie && ie[1] >= MOBILITY_DOMAIN_ID_LEN)
162 		md = ie + 2;
163 	wpa_sm_set_ft_params(wpa_s->wpa, ie, ie ? 2 + ie[1] : 0);
164 	if (md) {
165 		/* Prepare for the next transition */
166 		wpa_ft_prepare_auth_request(wpa_s->wpa, ie);
167 	}
168 
169 	if (md && ssid->key_mgmt & (WPA_KEY_MGMT_FT_PSK |
170 				    WPA_KEY_MGMT_FT_IEEE8021X)) {
171 		if (wpa_s->sme.assoc_req_ie_len + 5 <
172 		    sizeof(wpa_s->sme.assoc_req_ie)) {
173 			struct rsn_mdie *mdie;
174 			u8 *pos = wpa_s->sme.assoc_req_ie +
175 				wpa_s->sme.assoc_req_ie_len;
176 			*pos++ = WLAN_EID_MOBILITY_DOMAIN;
177 			*pos++ = sizeof(*mdie);
178 			mdie = (struct rsn_mdie *) pos;
179 			os_memcpy(mdie->mobility_domain, md,
180 				  MOBILITY_DOMAIN_ID_LEN);
181 			mdie->ft_capab = md[MOBILITY_DOMAIN_ID_LEN];
182 			wpa_s->sme.assoc_req_ie_len += 5;
183 		}
184 
185 		if (wpa_s->sme.ft_used &&
186 		    os_memcmp(md, wpa_s->sme.mobility_domain, 2) == 0 &&
187 		    wpa_sm_has_ptk(wpa_s->wpa)) {
188 			wpa_printf(MSG_DEBUG, "SME: Trying to use FT "
189 				   "over-the-air");
190 			params.auth_alg = WPA_AUTH_ALG_FT;
191 			params.ie = wpa_s->sme.ft_ies;
192 			params.ie_len = wpa_s->sme.ft_ies_len;
193 		}
194 	}
195 #endif /* CONFIG_IEEE80211R */
196 
197 #ifdef CONFIG_IEEE80211W
198 	wpa_s->sme.mfp = ssid->ieee80211w;
199 	if (ssid->ieee80211w != NO_MGMT_FRAME_PROTECTION) {
200 		const u8 *rsn = wpa_bss_get_ie(bss, WLAN_EID_RSN);
201 		struct wpa_ie_data _ie;
202 		if (rsn && wpa_parse_wpa_ie(rsn, 2 + rsn[1], &_ie) == 0 &&
203 		    _ie.capabilities &
204 		    (WPA_CAPABILITY_MFPC | WPA_CAPABILITY_MFPR)) {
205 			wpa_printf(MSG_DEBUG, "WPA: Selected AP supports MFP: "
206 				   "require MFP");
207 			wpa_s->sme.mfp = MGMT_FRAME_PROTECTION_REQUIRED;
208 		}
209 	}
210 #endif /* CONFIG_IEEE80211W */
211 
212 	wpa_supplicant_cancel_scan(wpa_s);
213 
214 	wpa_msg(wpa_s, MSG_INFO, "Trying to authenticate with " MACSTR
215 		" (SSID='%s' freq=%d MHz)", MAC2STR(params.bssid),
216 		wpa_ssid_txt(params.ssid, params.ssid_len), params.freq);
217 
218 	wpa_clear_keys(wpa_s, bss->bssid);
219 	wpa_supplicant_set_state(wpa_s, WPA_AUTHENTICATING);
220 	old_ssid = wpa_s->current_ssid;
221 	wpa_s->current_ssid = ssid;
222 	wpa_supplicant_rsn_supp_set_config(wpa_s, wpa_s->current_ssid);
223 	wpa_supplicant_initiate_eapol(wpa_s);
224 	if (old_ssid != wpa_s->current_ssid)
225 		wpas_notify_network_changed(wpa_s);
226 
227 	wpa_s->sme.auth_alg = params.auth_alg;
228 	if (wpa_drv_authenticate(wpa_s, &params) < 0) {
229 		wpa_msg(wpa_s, MSG_INFO, "Authentication request to the "
230 			"driver failed");
231 		wpa_supplicant_req_scan(wpa_s, 1, 0);
232 		return;
233 	}
234 
235 	/* TODO: add timeout on authentication */
236 
237 	/*
238 	 * Association will be started based on the authentication event from
239 	 * the driver.
240 	 */
241 }
242 
243 
244 void sme_event_auth(struct wpa_supplicant *wpa_s, union wpa_event_data *data)
245 {
246 	struct wpa_ssid *ssid = wpa_s->current_ssid;
247 
248 	if (ssid == NULL) {
249 		wpa_printf(MSG_DEBUG, "SME: Ignore authentication event when "
250 			   "network is not selected");
251 		return;
252 	}
253 
254 	if (wpa_s->wpa_state != WPA_AUTHENTICATING) {
255 		wpa_printf(MSG_DEBUG, "SME: Ignore authentication event when "
256 			   "not in authenticating state");
257 		return;
258 	}
259 
260 	if (os_memcmp(wpa_s->pending_bssid, data->auth.peer, ETH_ALEN) != 0) {
261 		wpa_printf(MSG_DEBUG, "SME: Ignore authentication with "
262 			   "unexpected peer " MACSTR,
263 			   MAC2STR(data->auth.peer));
264 		return;
265 	}
266 
267 	wpa_printf(MSG_DEBUG, "SME: Authentication response: peer=" MACSTR
268 		   " auth_type=%d status_code=%d",
269 		   MAC2STR(data->auth.peer), data->auth.auth_type,
270 		   data->auth.status_code);
271 	wpa_hexdump(MSG_MSGDUMP, "SME: Authentication response IEs",
272 		    data->auth.ies, data->auth.ies_len);
273 
274 	if (data->auth.status_code != WLAN_STATUS_SUCCESS) {
275 		wpa_printf(MSG_DEBUG, "SME: Authentication failed (status "
276 			   "code %d)", data->auth.status_code);
277 
278 		if (data->auth.status_code !=
279 		    WLAN_STATUS_NOT_SUPPORTED_AUTH_ALG ||
280 		    wpa_s->sme.auth_alg == data->auth.auth_type ||
281 		    wpa_s->current_ssid->auth_alg == WPA_AUTH_ALG_LEAP)
282 			return;
283 
284 		switch (data->auth.auth_type) {
285 		case WLAN_AUTH_OPEN:
286 			wpa_s->current_ssid->auth_alg = WPA_AUTH_ALG_SHARED;
287 
288 			wpa_printf(MSG_DEBUG, "SME: Trying SHARED auth");
289 			wpa_supplicant_associate(wpa_s, wpa_s->current_bss,
290 						 wpa_s->current_ssid);
291 			return;
292 
293 		case WLAN_AUTH_SHARED_KEY:
294 			wpa_s->current_ssid->auth_alg = WPA_AUTH_ALG_LEAP;
295 
296 			wpa_printf(MSG_DEBUG, "SME: Trying LEAP auth");
297 			wpa_supplicant_associate(wpa_s, wpa_s->current_bss,
298 						 wpa_s->current_ssid);
299 			return;
300 
301 		default:
302 			return;
303 		}
304 	}
305 
306 #ifdef CONFIG_IEEE80211R
307 	if (data->auth.auth_type == WLAN_AUTH_FT) {
308 		union wpa_event_data edata;
309 		os_memset(&edata, 0, sizeof(edata));
310 		edata.ft_ies.ies = data->auth.ies;
311 		edata.ft_ies.ies_len = data->auth.ies_len;
312 		os_memcpy(edata.ft_ies.target_ap, data->auth.peer, ETH_ALEN);
313 		wpa_supplicant_event(wpa_s, EVENT_FT_RESPONSE, &edata);
314 	}
315 #endif /* CONFIG_IEEE80211R */
316 
317 	sme_associate(wpa_s, ssid->mode, data->auth.peer,
318 		      data->auth.auth_type);
319 }
320 
321 
322 void sme_associate(struct wpa_supplicant *wpa_s, enum wpas_mode mode,
323 		   const u8 *bssid, u16 auth_type)
324 {
325 	struct wpa_driver_associate_params params;
326 	struct ieee802_11_elems elems;
327 
328 	os_memset(&params, 0, sizeof(params));
329 	params.bssid = bssid;
330 	params.ssid = wpa_s->sme.ssid;
331 	params.ssid_len = wpa_s->sme.ssid_len;
332 	params.freq = wpa_s->sme.freq;
333 	params.wpa_ie = wpa_s->sme.assoc_req_ie_len ?
334 		wpa_s->sme.assoc_req_ie : NULL;
335 	params.wpa_ie_len = wpa_s->sme.assoc_req_ie_len;
336 #ifdef CONFIG_IEEE80211R
337 	if (auth_type == WLAN_AUTH_FT && wpa_s->sme.ft_ies) {
338 		params.wpa_ie = wpa_s->sme.ft_ies;
339 		params.wpa_ie_len = wpa_s->sme.ft_ies_len;
340 	}
341 #endif /* CONFIG_IEEE80211R */
342 	params.mode = mode;
343 	params.mgmt_frame_protection = wpa_s->sme.mfp;
344 	if (wpa_s->sme.prev_bssid_set)
345 		params.prev_bssid = wpa_s->sme.prev_bssid;
346 
347 	wpa_msg(wpa_s, MSG_INFO, "Trying to associate with " MACSTR
348 		" (SSID='%s' freq=%d MHz)", MAC2STR(params.bssid),
349 		params.ssid ? wpa_ssid_txt(params.ssid, params.ssid_len) : "",
350 		params.freq);
351 
352 	wpa_supplicant_set_state(wpa_s, WPA_ASSOCIATING);
353 
354 	if (params.wpa_ie == NULL ||
355 	    ieee802_11_parse_elems(params.wpa_ie, params.wpa_ie_len, &elems, 0)
356 	    < 0) {
357 		wpa_printf(MSG_DEBUG, "SME: Could not parse own IEs?!");
358 		os_memset(&elems, 0, sizeof(elems));
359 	}
360 	if (elems.rsn_ie)
361 		wpa_sm_set_assoc_wpa_ie(wpa_s->wpa, elems.rsn_ie - 2,
362 					elems.rsn_ie_len + 2);
363 	else if (elems.wpa_ie)
364 		wpa_sm_set_assoc_wpa_ie(wpa_s->wpa, elems.wpa_ie - 2,
365 					elems.wpa_ie_len + 2);
366 	else
367 		wpa_sm_set_assoc_wpa_ie(wpa_s->wpa, NULL, 0);
368 
369 	if (wpa_drv_associate(wpa_s, &params) < 0) {
370 		wpa_msg(wpa_s, MSG_INFO, "Association request to the driver "
371 			"failed");
372 		wpa_supplicant_req_scan(wpa_s, 5, 0);
373 		return;
374 	}
375 
376 	/* TODO: add timeout on association */
377 }
378 
379 
380 int sme_update_ft_ies(struct wpa_supplicant *wpa_s, const u8 *md,
381 		      const u8 *ies, size_t ies_len)
382 {
383 	if (md == NULL || ies == NULL) {
384 		wpa_printf(MSG_DEBUG, "SME: Remove mobility domain");
385 		os_free(wpa_s->sme.ft_ies);
386 		wpa_s->sme.ft_ies = NULL;
387 		wpa_s->sme.ft_ies_len = 0;
388 		wpa_s->sme.ft_used = 0;
389 		return 0;
390 	}
391 
392 	os_memcpy(wpa_s->sme.mobility_domain, md, MOBILITY_DOMAIN_ID_LEN);
393 	wpa_hexdump(MSG_DEBUG, "SME: FT IEs", ies, ies_len);
394 	os_free(wpa_s->sme.ft_ies);
395 	wpa_s->sme.ft_ies = os_malloc(ies_len);
396 	if (wpa_s->sme.ft_ies == NULL)
397 		return -1;
398 	os_memcpy(wpa_s->sme.ft_ies, ies, ies_len);
399 	wpa_s->sme.ft_ies_len = ies_len;
400 	return 0;
401 }
402 
403 
404 void sme_event_assoc_reject(struct wpa_supplicant *wpa_s,
405 			    union wpa_event_data *data)
406 {
407 	int bssid_changed;
408 	int timeout = 5000;
409 
410 	wpa_printf(MSG_DEBUG, "SME: Association with " MACSTR " failed: "
411 		   "status code %d", MAC2STR(wpa_s->pending_bssid),
412 		   data->assoc_reject.status_code);
413 
414 	bssid_changed = !is_zero_ether_addr(wpa_s->bssid);
415 
416 	/*
417 	 * For now, unconditionally terminate the previous authentication. In
418 	 * theory, this should not be needed, but mac80211 gets quite confused
419 	 * if the authentication is left pending.. Some roaming cases might
420 	 * benefit from using the previous authentication, so this could be
421 	 * optimized in the future.
422 	 */
423 	if (wpa_drv_deauthenticate(wpa_s, wpa_s->pending_bssid,
424 				   WLAN_REASON_DEAUTH_LEAVING) < 0) {
425 		wpa_msg(wpa_s, MSG_INFO,
426 			"Deauth request to the driver failed");
427 	}
428 	wpa_s->sme.prev_bssid_set = 0;
429 
430 	if (wpa_blacklist_add(wpa_s, wpa_s->pending_bssid) == 0) {
431 		struct wpa_blacklist *b;
432 		b = wpa_blacklist_get(wpa_s, wpa_s->pending_bssid);
433 		if (b && b->count < 3) {
434 			/*
435 			 * Speed up next attempt if there could be other APs
436 			 * that could accept association.
437 			 */
438 			timeout = 100;
439 		}
440 	}
441 	wpa_supplicant_set_state(wpa_s, WPA_DISCONNECTED);
442 	os_memset(wpa_s->bssid, 0, ETH_ALEN);
443 	os_memset(wpa_s->pending_bssid, 0, ETH_ALEN);
444 	if (bssid_changed)
445 		wpas_notify_bssid_changed(wpa_s);
446 
447 	/*
448 	 * TODO: if more than one possible AP is available in scan results,
449 	 * could try the other ones before requesting a new scan.
450 	 */
451 	wpa_supplicant_req_scan(wpa_s, timeout / 1000,
452 				1000 * (timeout % 1000));
453 }
454 
455 
456 void sme_event_auth_timed_out(struct wpa_supplicant *wpa_s,
457 			      union wpa_event_data *data)
458 {
459 	wpa_printf(MSG_DEBUG, "SME: Authentication timed out");
460 	wpa_supplicant_req_scan(wpa_s, 5, 0);
461 }
462 
463 
464 void sme_event_assoc_timed_out(struct wpa_supplicant *wpa_s,
465 			       union wpa_event_data *data)
466 {
467 	wpa_printf(MSG_DEBUG, "SME: Association timed out");
468 	wpa_supplicant_mark_disassoc(wpa_s);
469 	wpa_supplicant_req_scan(wpa_s, 5, 0);
470 }
471 
472 
473 void sme_event_disassoc(struct wpa_supplicant *wpa_s,
474 			union wpa_event_data *data)
475 {
476 	wpa_printf(MSG_DEBUG, "SME: Disassociation event received");
477 	if (wpa_s->sme.prev_bssid_set &&
478 	    !(wpa_s->drv_flags & WPA_DRIVER_FLAGS_USER_SPACE_MLME)) {
479 		/*
480 		 * cfg80211/mac80211 can get into somewhat confused state if
481 		 * the AP only disassociates us and leaves us in authenticated
482 		 * state. For now, force the state to be cleared to avoid
483 		 * confusing errors if we try to associate with the AP again.
484 		 */
485 		wpa_printf(MSG_DEBUG, "SME: Deauthenticate to clear driver "
486 			   "state");
487 		wpa_drv_deauthenticate(wpa_s, wpa_s->sme.prev_bssid,
488 				       WLAN_REASON_DEAUTH_LEAVING);
489 	}
490 }
491