xref: /netbsd-src/external/bsd/wpa/dist/wpa_supplicant/sme.c (revision d25ffa98a4bfca1fe272f3c182496ec9934faac7)
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 		return;
232 	}
233 
234 	/* TODO: add timeout on authentication */
235 
236 	/*
237 	 * Association will be started based on the authentication event from
238 	 * the driver.
239 	 */
240 }
241 
242 
243 void sme_event_auth(struct wpa_supplicant *wpa_s, union wpa_event_data *data)
244 {
245 	struct wpa_ssid *ssid = wpa_s->current_ssid;
246 
247 	if (ssid == NULL) {
248 		wpa_printf(MSG_DEBUG, "SME: Ignore authentication event when "
249 			   "network is not selected");
250 		return;
251 	}
252 
253 	if (wpa_s->wpa_state != WPA_AUTHENTICATING) {
254 		wpa_printf(MSG_DEBUG, "SME: Ignore authentication event when "
255 			   "not in authenticating state");
256 		return;
257 	}
258 
259 	if (os_memcmp(wpa_s->pending_bssid, data->auth.peer, ETH_ALEN) != 0) {
260 		wpa_printf(MSG_DEBUG, "SME: Ignore authentication with "
261 			   "unexpected peer " MACSTR,
262 			   MAC2STR(data->auth.peer));
263 		return;
264 	}
265 
266 	wpa_printf(MSG_DEBUG, "SME: Authentication response: peer=" MACSTR
267 		   " auth_type=%d status_code=%d",
268 		   MAC2STR(data->auth.peer), data->auth.auth_type,
269 		   data->auth.status_code);
270 	wpa_hexdump(MSG_MSGDUMP, "SME: Authentication response IEs",
271 		    data->auth.ies, data->auth.ies_len);
272 
273 	if (data->auth.status_code != WLAN_STATUS_SUCCESS) {
274 		wpa_printf(MSG_DEBUG, "SME: Authentication failed (status "
275 			   "code %d)", data->auth.status_code);
276 		return;
277 	}
278 
279 #ifdef CONFIG_IEEE80211R
280 	if (data->auth.auth_type == WLAN_AUTH_FT) {
281 		union wpa_event_data edata;
282 		os_memset(&edata, 0, sizeof(edata));
283 		edata.ft_ies.ies = data->auth.ies;
284 		edata.ft_ies.ies_len = data->auth.ies_len;
285 		os_memcpy(edata.ft_ies.target_ap, data->auth.peer, ETH_ALEN);
286 		wpa_supplicant_event(wpa_s, EVENT_FT_RESPONSE, &edata);
287 	}
288 #endif /* CONFIG_IEEE80211R */
289 
290 	sme_associate(wpa_s, ssid->mode, data->auth.peer,
291 		      data->auth.auth_type);
292 }
293 
294 
295 void sme_associate(struct wpa_supplicant *wpa_s, enum wpas_mode mode,
296 		   const u8 *bssid, u16 auth_type)
297 {
298 	struct wpa_driver_associate_params params;
299 	struct ieee802_11_elems elems;
300 
301 	os_memset(&params, 0, sizeof(params));
302 	params.bssid = bssid;
303 	params.ssid = wpa_s->sme.ssid;
304 	params.ssid_len = wpa_s->sme.ssid_len;
305 	params.freq = wpa_s->sme.freq;
306 	params.wpa_ie = wpa_s->sme.assoc_req_ie_len ?
307 		wpa_s->sme.assoc_req_ie : NULL;
308 	params.wpa_ie_len = wpa_s->sme.assoc_req_ie_len;
309 #ifdef CONFIG_IEEE80211R
310 	if (auth_type == WLAN_AUTH_FT && wpa_s->sme.ft_ies) {
311 		params.wpa_ie = wpa_s->sme.ft_ies;
312 		params.wpa_ie_len = wpa_s->sme.ft_ies_len;
313 	}
314 #endif /* CONFIG_IEEE80211R */
315 	params.mode = mode;
316 	params.mgmt_frame_protection = wpa_s->sme.mfp;
317 	if (wpa_s->sme.prev_bssid_set)
318 		params.prev_bssid = wpa_s->sme.prev_bssid;
319 
320 	wpa_msg(wpa_s, MSG_INFO, "Trying to associate with " MACSTR
321 		" (SSID='%s' freq=%d MHz)", MAC2STR(params.bssid),
322 		params.ssid ? wpa_ssid_txt(params.ssid, params.ssid_len) : "",
323 		params.freq);
324 
325 	wpa_supplicant_set_state(wpa_s, WPA_ASSOCIATING);
326 
327 	if (params.wpa_ie == NULL ||
328 	    ieee802_11_parse_elems(params.wpa_ie, params.wpa_ie_len, &elems, 0)
329 	    < 0) {
330 		wpa_printf(MSG_DEBUG, "SME: Could not parse own IEs?!");
331 		os_memset(&elems, 0, sizeof(elems));
332 	}
333 	if (elems.rsn_ie)
334 		wpa_sm_set_assoc_wpa_ie(wpa_s->wpa, elems.rsn_ie - 2,
335 					elems.rsn_ie_len + 2);
336 	else if (elems.wpa_ie)
337 		wpa_sm_set_assoc_wpa_ie(wpa_s->wpa, elems.wpa_ie - 2,
338 					elems.wpa_ie_len + 2);
339 	else
340 		wpa_sm_set_assoc_wpa_ie(wpa_s->wpa, NULL, 0);
341 
342 	if (wpa_drv_associate(wpa_s, &params) < 0) {
343 		wpa_msg(wpa_s, MSG_INFO, "Association request to the driver "
344 			"failed");
345 		wpa_supplicant_req_scan(wpa_s, 5, 0);
346 		return;
347 	}
348 
349 	/* TODO: add timeout on association */
350 }
351 
352 
353 int sme_update_ft_ies(struct wpa_supplicant *wpa_s, const u8 *md,
354 		      const u8 *ies, size_t ies_len)
355 {
356 	if (md == NULL || ies == NULL) {
357 		wpa_printf(MSG_DEBUG, "SME: Remove mobility domain");
358 		os_free(wpa_s->sme.ft_ies);
359 		wpa_s->sme.ft_ies = NULL;
360 		wpa_s->sme.ft_ies_len = 0;
361 		wpa_s->sme.ft_used = 0;
362 		return 0;
363 	}
364 
365 	os_memcpy(wpa_s->sme.mobility_domain, md, MOBILITY_DOMAIN_ID_LEN);
366 	wpa_hexdump(MSG_DEBUG, "SME: FT IEs", ies, ies_len);
367 	os_free(wpa_s->sme.ft_ies);
368 	wpa_s->sme.ft_ies = os_malloc(ies_len);
369 	if (wpa_s->sme.ft_ies == NULL)
370 		return -1;
371 	os_memcpy(wpa_s->sme.ft_ies, ies, ies_len);
372 	wpa_s->sme.ft_ies_len = ies_len;
373 	return 0;
374 }
375 
376 
377 void sme_event_assoc_reject(struct wpa_supplicant *wpa_s,
378 			    union wpa_event_data *data)
379 {
380 	int bssid_changed;
381 	int timeout = 5000;
382 
383 	wpa_printf(MSG_DEBUG, "SME: Association with " MACSTR " failed: "
384 		   "status code %d", MAC2STR(wpa_s->pending_bssid),
385 		   data->assoc_reject.status_code);
386 
387 	bssid_changed = !is_zero_ether_addr(wpa_s->bssid);
388 
389 	/*
390 	 * For now, unconditionally terminate the previous authentication. In
391 	 * theory, this should not be needed, but mac80211 gets quite confused
392 	 * if the authentication is left pending.. Some roaming cases might
393 	 * benefit from using the previous authentication, so this could be
394 	 * optimized in the future.
395 	 */
396 	if (wpa_drv_deauthenticate(wpa_s, wpa_s->pending_bssid,
397 				   WLAN_REASON_DEAUTH_LEAVING) < 0) {
398 		wpa_msg(wpa_s, MSG_INFO,
399 			"Deauth request to the driver failed");
400 	}
401 	wpa_s->sme.prev_bssid_set = 0;
402 
403 	if (wpa_blacklist_add(wpa_s, wpa_s->pending_bssid) == 0) {
404 		struct wpa_blacklist *b;
405 		b = wpa_blacklist_get(wpa_s, wpa_s->pending_bssid);
406 		if (b && b->count < 3) {
407 			/*
408 			 * Speed up next attempt if there could be other APs
409 			 * that could accept association.
410 			 */
411 			timeout = 100;
412 		}
413 	}
414 	wpa_supplicant_set_state(wpa_s, WPA_DISCONNECTED);
415 	os_memset(wpa_s->bssid, 0, ETH_ALEN);
416 	os_memset(wpa_s->pending_bssid, 0, ETH_ALEN);
417 	if (bssid_changed)
418 		wpas_notify_bssid_changed(wpa_s);
419 
420 	/*
421 	 * TODO: if more than one possible AP is available in scan results,
422 	 * could try the other ones before requesting a new scan.
423 	 */
424 	wpa_supplicant_req_scan(wpa_s, timeout / 1000,
425 				1000 * (timeout % 1000));
426 }
427 
428 
429 void sme_event_auth_timed_out(struct wpa_supplicant *wpa_s,
430 			      union wpa_event_data *data)
431 {
432 	wpa_printf(MSG_DEBUG, "SME: Authentication timed out");
433 	wpa_supplicant_req_scan(wpa_s, 5, 0);
434 }
435 
436 
437 void sme_event_assoc_timed_out(struct wpa_supplicant *wpa_s,
438 			       union wpa_event_data *data)
439 {
440 	wpa_printf(MSG_DEBUG, "SME: Association timed out");
441 	wpa_supplicant_mark_disassoc(wpa_s);
442 	wpa_supplicant_req_scan(wpa_s, 5, 0);
443 }
444 
445 
446 void sme_event_disassoc(struct wpa_supplicant *wpa_s,
447 			union wpa_event_data *data)
448 {
449 	wpa_printf(MSG_DEBUG, "SME: Disassociation event received");
450 	if (!is_zero_ether_addr(wpa_s->bssid) &&
451 	    !(wpa_s->drv_flags & WPA_DRIVER_FLAGS_USER_SPACE_MLME)) {
452 		/*
453 		 * cfg80211/mac80211 can get into somewhat confused state if
454 		 * the AP only disassociates us and leaves us in authenticated
455 		 * state. For now, force the state to be cleared to avoid
456 		 * confusing errors if we try to associate with the AP again.
457 		 */
458 		wpa_printf(MSG_DEBUG, "SME: Deauthenticate to clear driver "
459 			   "state");
460 		wpa_drv_deauthenticate(wpa_s, wpa_s->bssid,
461 				       WLAN_REASON_DEAUTH_LEAVING);
462 	}
463 }
464