1 /*
2  * IEEE 802.1X-2010 KaY Interface
3  * Copyright (c) 2013-2014, Qualcomm Atheros, Inc.
4  *
5  * This software may be distributed under the terms of the BSD license.
6  * See README for more details.
7  */
8 
9 #include "utils/includes.h"
10 
11 #include "utils/common.h"
12 #include "eap_peer/eap.h"
13 #include "eap_peer/eap_i.h"
14 #include "eapol_supp/eapol_supp_sm.h"
15 #include "pae/ieee802_1x_key.h"
16 #include "pae/ieee802_1x_kay.h"
17 #include "wpa_supplicant_i.h"
18 #include "config.h"
19 #include "config_ssid.h"
20 #include "driver_i.h"
21 #include "wpas_kay.h"
22 
23 
24 #define DEFAULT_KEY_LEN		16
25 /* secure Connectivity Association Key Name (CKN) */
26 #define DEFAULT_CKN_LEN		16
27 
28 
wpas_macsec_init(void * priv,struct macsec_init_params * params)29 static int wpas_macsec_init(void *priv, struct macsec_init_params *params)
30 {
31 	return wpa_drv_macsec_init(priv, params);
32 }
33 
34 
wpas_macsec_deinit(void * priv)35 static int wpas_macsec_deinit(void *priv)
36 {
37 	return wpa_drv_macsec_deinit(priv);
38 }
39 
40 
wpas_macsec_get_capability(void * priv,enum macsec_cap * cap)41 static int wpas_macsec_get_capability(void *priv, enum macsec_cap *cap)
42 {
43 	return wpa_drv_macsec_get_capability(priv, cap);
44 }
45 
46 
wpas_enable_protect_frames(void * wpa_s,bool enabled)47 static int wpas_enable_protect_frames(void *wpa_s, bool enabled)
48 {
49 	return wpa_drv_enable_protect_frames(wpa_s, enabled);
50 }
51 
52 
wpas_enable_encrypt(void * wpa_s,bool enabled)53 static int wpas_enable_encrypt(void *wpa_s, bool enabled)
54 {
55 	return wpa_drv_enable_encrypt(wpa_s, enabled);
56 }
57 
58 
wpas_set_replay_protect(void * wpa_s,bool enabled,u32 window)59 static int wpas_set_replay_protect(void *wpa_s, bool enabled, u32 window)
60 {
61 	return wpa_drv_set_replay_protect(wpa_s, enabled, window);
62 }
63 
64 
wpas_set_current_cipher_suite(void * wpa_s,u64 cs)65 static int wpas_set_current_cipher_suite(void *wpa_s, u64 cs)
66 {
67 	return wpa_drv_set_current_cipher_suite(wpa_s, cs);
68 }
69 
70 
wpas_enable_controlled_port(void * wpa_s,bool enabled)71 static int wpas_enable_controlled_port(void *wpa_s, bool enabled)
72 {
73 	return wpa_drv_enable_controlled_port(wpa_s, enabled);
74 }
75 
76 
wpas_get_receive_lowest_pn(void * wpa_s,struct receive_sa * sa)77 static int wpas_get_receive_lowest_pn(void *wpa_s, struct receive_sa *sa)
78 {
79 	return wpa_drv_get_receive_lowest_pn(wpa_s, sa);
80 }
81 
82 
wpas_get_transmit_next_pn(void * wpa_s,struct transmit_sa * sa)83 static int wpas_get_transmit_next_pn(void *wpa_s, struct transmit_sa *sa)
84 {
85 	return wpa_drv_get_transmit_next_pn(wpa_s, sa);
86 }
87 
88 
wpas_set_transmit_next_pn(void * wpa_s,struct transmit_sa * sa)89 static int wpas_set_transmit_next_pn(void *wpa_s, struct transmit_sa *sa)
90 {
91 	return wpa_drv_set_transmit_next_pn(wpa_s, sa);
92 }
93 
94 
wpas_set_receive_lowest_pn(void * wpa_s,struct receive_sa * sa)95 static int wpas_set_receive_lowest_pn(void *wpa_s, struct receive_sa *sa)
96 {
97 	return wpa_drv_set_receive_lowest_pn(wpa_s, sa);
98 }
99 
100 
wpas_set_offload(void * wpa_s,u8 offload)101 static int wpas_set_offload(void *wpa_s, u8 offload)
102 {
103 	return wpa_drv_set_offload(wpa_s, offload);
104 }
105 
106 
conf_offset_val(enum confidentiality_offset co)107 static unsigned int conf_offset_val(enum confidentiality_offset co)
108 {
109 	switch (co) {
110 	case CONFIDENTIALITY_OFFSET_30:
111 		return 30;
112 	case CONFIDENTIALITY_OFFSET_50:
113 		return 50;
114 	default:
115 		return 0;
116 	}
117 }
118 
119 
wpas_create_receive_sc(void * wpa_s,struct receive_sc * sc,enum validate_frames vf,enum confidentiality_offset co)120 static int wpas_create_receive_sc(void *wpa_s, struct receive_sc *sc,
121 				  enum validate_frames vf,
122 				  enum confidentiality_offset co)
123 {
124 	return wpa_drv_create_receive_sc(wpa_s, sc, conf_offset_val(co), vf);
125 }
126 
127 
wpas_delete_receive_sc(void * wpa_s,struct receive_sc * sc)128 static int wpas_delete_receive_sc(void *wpa_s, struct receive_sc *sc)
129 {
130 	return wpa_drv_delete_receive_sc(wpa_s, sc);
131 }
132 
133 
wpas_create_receive_sa(void * wpa_s,struct receive_sa * sa)134 static int wpas_create_receive_sa(void *wpa_s, struct receive_sa *sa)
135 {
136 	return wpa_drv_create_receive_sa(wpa_s, sa);
137 }
138 
139 
wpas_delete_receive_sa(void * wpa_s,struct receive_sa * sa)140 static int wpas_delete_receive_sa(void *wpa_s, struct receive_sa *sa)
141 {
142 	return wpa_drv_delete_receive_sa(wpa_s, sa);
143 }
144 
145 
wpas_enable_receive_sa(void * wpa_s,struct receive_sa * sa)146 static int wpas_enable_receive_sa(void *wpa_s, struct receive_sa *sa)
147 {
148 	return wpa_drv_enable_receive_sa(wpa_s, sa);
149 }
150 
151 
wpas_disable_receive_sa(void * wpa_s,struct receive_sa * sa)152 static int wpas_disable_receive_sa(void *wpa_s, struct receive_sa *sa)
153 {
154 	return wpa_drv_disable_receive_sa(wpa_s, sa);
155 }
156 
157 
158 static int
wpas_create_transmit_sc(void * wpa_s,struct transmit_sc * sc,enum confidentiality_offset co)159 wpas_create_transmit_sc(void *wpa_s, struct transmit_sc *sc,
160 			enum confidentiality_offset co)
161 {
162 	return wpa_drv_create_transmit_sc(wpa_s, sc, conf_offset_val(co));
163 }
164 
165 
wpas_delete_transmit_sc(void * wpa_s,struct transmit_sc * sc)166 static int wpas_delete_transmit_sc(void *wpa_s, struct transmit_sc *sc)
167 {
168 	return wpa_drv_delete_transmit_sc(wpa_s, sc);
169 }
170 
171 
wpas_create_transmit_sa(void * wpa_s,struct transmit_sa * sa)172 static int wpas_create_transmit_sa(void *wpa_s, struct transmit_sa *sa)
173 {
174 	return wpa_drv_create_transmit_sa(wpa_s, sa);
175 }
176 
177 
wpas_delete_transmit_sa(void * wpa_s,struct transmit_sa * sa)178 static int wpas_delete_transmit_sa(void *wpa_s, struct transmit_sa *sa)
179 {
180 	return wpa_drv_delete_transmit_sa(wpa_s, sa);
181 }
182 
183 
wpas_enable_transmit_sa(void * wpa_s,struct transmit_sa * sa)184 static int wpas_enable_transmit_sa(void *wpa_s, struct transmit_sa *sa)
185 {
186 	return wpa_drv_enable_transmit_sa(wpa_s, sa);
187 }
188 
189 
wpas_disable_transmit_sa(void * wpa_s,struct transmit_sa * sa)190 static int wpas_disable_transmit_sa(void *wpa_s, struct transmit_sa *sa)
191 {
192 	return wpa_drv_disable_transmit_sa(wpa_s, sa);
193 }
194 
195 
ieee802_1x_alloc_kay_sm(struct wpa_supplicant * wpa_s,struct wpa_ssid * ssid)196 int ieee802_1x_alloc_kay_sm(struct wpa_supplicant *wpa_s, struct wpa_ssid *ssid)
197 {
198 	struct ieee802_1x_kay_ctx *kay_ctx;
199 	struct ieee802_1x_kay *res = NULL;
200 	enum macsec_policy policy;
201 
202 	ieee802_1x_dealloc_kay_sm(wpa_s);
203 
204 	if (!ssid || ssid->macsec_policy == 0)
205 		return 0;
206 
207 	if (ssid->macsec_policy == 1) {
208 		if (ssid->macsec_integ_only == 1)
209 			policy = SHOULD_SECURE;
210 		else
211 			policy = SHOULD_ENCRYPT;
212 	} else {
213 		policy = DO_NOT_SECURE;
214 	}
215 
216 	kay_ctx = os_zalloc(sizeof(*kay_ctx));
217 	if (!kay_ctx)
218 		return -1;
219 
220 	kay_ctx->ctx = wpa_s;
221 
222 	kay_ctx->macsec_init = wpas_macsec_init;
223 	kay_ctx->macsec_deinit = wpas_macsec_deinit;
224 	kay_ctx->macsec_get_capability = wpas_macsec_get_capability;
225 	kay_ctx->enable_protect_frames = wpas_enable_protect_frames;
226 	kay_ctx->enable_encrypt = wpas_enable_encrypt;
227 	kay_ctx->set_replay_protect = wpas_set_replay_protect;
228 	kay_ctx->set_offload = wpas_set_offload;
229 	kay_ctx->set_current_cipher_suite = wpas_set_current_cipher_suite;
230 	kay_ctx->enable_controlled_port = wpas_enable_controlled_port;
231 	kay_ctx->get_receive_lowest_pn = wpas_get_receive_lowest_pn;
232 	kay_ctx->get_transmit_next_pn = wpas_get_transmit_next_pn;
233 	kay_ctx->set_transmit_next_pn = wpas_set_transmit_next_pn;
234 	kay_ctx->set_receive_lowest_pn = wpas_set_receive_lowest_pn;
235 	kay_ctx->create_receive_sc = wpas_create_receive_sc;
236 	kay_ctx->delete_receive_sc = wpas_delete_receive_sc;
237 	kay_ctx->create_receive_sa = wpas_create_receive_sa;
238 	kay_ctx->delete_receive_sa = wpas_delete_receive_sa;
239 	kay_ctx->enable_receive_sa = wpas_enable_receive_sa;
240 	kay_ctx->disable_receive_sa = wpas_disable_receive_sa;
241 	kay_ctx->create_transmit_sc = wpas_create_transmit_sc;
242 	kay_ctx->delete_transmit_sc = wpas_delete_transmit_sc;
243 	kay_ctx->create_transmit_sa = wpas_create_transmit_sa;
244 	kay_ctx->delete_transmit_sa = wpas_delete_transmit_sa;
245 	kay_ctx->enable_transmit_sa = wpas_enable_transmit_sa;
246 	kay_ctx->disable_transmit_sa = wpas_disable_transmit_sa;
247 
248 	res = ieee802_1x_kay_init(kay_ctx, policy, ssid->macsec_replay_protect,
249 				  ssid->macsec_replay_window,
250 				  ssid->macsec_offload, ssid->macsec_port,
251 				  ssid->mka_priority, ssid->macsec_csindex,
252 				  ssid->macsec_icv_indicator,
253 				  wpa_s->ifname, wpa_s->own_addr);
254 	/* ieee802_1x_kay_init() frees kay_ctx on failure */
255 	if (res == NULL)
256 		return -1;
257 
258 	wpa_s->kay = res;
259 
260 	return 0;
261 }
262 
263 
ieee802_1x_dealloc_kay_sm(struct wpa_supplicant * wpa_s)264 void ieee802_1x_dealloc_kay_sm(struct wpa_supplicant *wpa_s)
265 {
266 	if (!wpa_s->kay)
267 		return;
268 
269 	ieee802_1x_kay_deinit(wpa_s->kay);
270 	wpa_s->kay = NULL;
271 }
272 
273 
ieee802_1x_auth_get_msk(struct wpa_supplicant * wpa_s,const u8 * addr,u8 * msk,size_t * len)274 static int ieee802_1x_auth_get_msk(struct wpa_supplicant *wpa_s, const u8 *addr,
275 				   u8 *msk, size_t *len)
276 {
277 	u8 key[EAP_MSK_LEN];
278 	size_t keylen;
279 	struct eapol_sm *sm;
280 	int res;
281 
282 	sm = wpa_s->eapol;
283 	if (sm == NULL)
284 		return -1;
285 
286 	keylen = EAP_MSK_LEN;
287 	res = eapol_sm_get_key(sm, key, keylen);
288 	if (res) {
289 		wpa_printf(MSG_DEBUG,
290 			   "Failed to get MSK from EAPOL state machines");
291 		return -1;
292 	}
293 
294 	if (keylen > *len)
295 		keylen = *len;
296 	os_memcpy(msk, key, keylen);
297 	*len = keylen;
298 
299 	return 0;
300 }
301 
302 
ieee802_1x_notify_create_actor(struct wpa_supplicant * wpa_s,const u8 * peer_addr)303 void * ieee802_1x_notify_create_actor(struct wpa_supplicant *wpa_s,
304 				      const u8 *peer_addr)
305 {
306 	const u8 *sid;
307 	size_t sid_len;
308 	struct mka_key_name *ckn;
309 	struct mka_key *cak;
310 	struct mka_key *msk;
311 	void *res = NULL;
312 
313 	if (!wpa_s->kay || wpa_s->kay->policy == DO_NOT_SECURE)
314 		return NULL;
315 
316 	wpa_printf(MSG_DEBUG,
317 		   "IEEE 802.1X: External notification - Create MKA for "
318 		   MACSTR, MAC2STR(peer_addr));
319 
320 	msk = os_zalloc(sizeof(*msk));
321 	ckn = os_zalloc(sizeof(*ckn));
322 	cak = os_zalloc(sizeof(*cak));
323 	if (!msk || !ckn || !cak)
324 		goto fail;
325 
326 	msk->len = DEFAULT_KEY_LEN;
327 	if (ieee802_1x_auth_get_msk(wpa_s, wpa_s->bssid, msk->key, &msk->len)) {
328 		wpa_printf(MSG_ERROR, "IEEE 802.1X: Could not get MSK");
329 		goto fail;
330 	}
331 
332 	sid = eapol_sm_get_session_id(wpa_s->eapol, &sid_len);
333 	if (!sid) {
334 		wpa_printf(MSG_ERROR,
335 			   "IEEE 802.1X: Could not get EAP Session Id");
336 		goto fail;
337 	}
338 
339 	/* Derive CAK from MSK */
340 	cak->len = DEFAULT_KEY_LEN;
341 	if (ieee802_1x_cak_aes_cmac(msk->key, msk->len, wpa_s->own_addr,
342 				    peer_addr, cak->key, cak->len)) {
343 		wpa_printf(MSG_ERROR,
344 			   "IEEE 802.1X: Deriving CAK failed");
345 		goto fail;
346 	}
347 	wpa_hexdump_key(MSG_DEBUG, "Derived CAK", cak->key, cak->len);
348 
349 	/* Derive CKN from MSK */
350 	ckn->len = DEFAULT_CKN_LEN;
351 	if (ieee802_1x_ckn_aes_cmac(msk->key, msk->len, wpa_s->own_addr,
352 				    peer_addr, sid, sid_len, ckn->name)) {
353 		wpa_printf(MSG_ERROR,
354 			   "IEEE 802.1X: Deriving CKN failed");
355 		goto fail;
356 	}
357 	wpa_hexdump(MSG_DEBUG, "Derived CKN", ckn->name, ckn->len);
358 
359 	res = ieee802_1x_kay_create_mka(wpa_s->kay, ckn, cak, 0,
360 					EAP_EXCHANGE, false);
361 
362 fail:
363 	if (msk) {
364 		os_memset(msk, 0, sizeof(*msk));
365 		os_free(msk);
366 	}
367 	os_free(ckn);
368 	if (cak) {
369 		os_memset(cak, 0, sizeof(*cak));
370 		os_free(cak);
371 	}
372 
373 	return res;
374 }
375 
376 
ieee802_1x_create_preshared_mka(struct wpa_supplicant * wpa_s,struct wpa_ssid * ssid)377 void * ieee802_1x_create_preshared_mka(struct wpa_supplicant *wpa_s,
378 				       struct wpa_ssid *ssid)
379 {
380 	struct mka_key *cak;
381 	struct mka_key_name *ckn;
382 	void *res = NULL;
383 
384 	if ((ssid->mka_psk_set & MKA_PSK_SET) != MKA_PSK_SET)
385 		goto end;
386 
387 	ckn = os_zalloc(sizeof(*ckn));
388 	if (!ckn)
389 		goto end;
390 
391 	cak = os_zalloc(sizeof(*cak));
392 	if (!cak)
393 		goto free_ckn;
394 
395 	if (ieee802_1x_alloc_kay_sm(wpa_s, ssid) < 0 || !wpa_s->kay)
396 		goto free_cak;
397 
398 	if (wpa_s->kay->policy == DO_NOT_SECURE)
399 		goto dealloc;
400 
401 	cak->len = ssid->mka_cak_len;
402 	os_memcpy(cak->key, ssid->mka_cak, cak->len);
403 
404 	ckn->len = ssid->mka_ckn_len;
405 	os_memcpy(ckn->name, ssid->mka_ckn, ckn->len);
406 
407 	res = ieee802_1x_kay_create_mka(wpa_s->kay, ckn, cak, 0, PSK, false);
408 	if (res)
409 		goto free_cak;
410 
411 dealloc:
412 	/* Failed to create MKA */
413 	ieee802_1x_dealloc_kay_sm(wpa_s);
414 free_cak:
415 	os_free(cak);
416 free_ckn:
417 	os_free(ckn);
418 end:
419 	return res;
420 }
421