xref: /freebsd/contrib/wpa/src/eap_server/eap_server.c (revision c1d255d3ffdbe447de3ab875bf4e7d7accc5bfc5)
1 /*
2  * hostapd / EAP Full Authenticator state machine (RFC 4137)
3  * Copyright (c) 2004-2014, 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  * This state machine is based on the full authenticator state machine defined
9  * in RFC 4137. However, to support backend authentication in RADIUS
10  * authentication server functionality, parts of backend authenticator (also
11  * from RFC 4137) are mixed in. This functionality is enabled by setting
12  * backend_auth configuration variable to true.
13  */
14 
15 #include "includes.h"
16 
17 #include "common.h"
18 #include "crypto/sha256.h"
19 #include "eap_i.h"
20 #include "state_machine.h"
21 #include "common/wpa_ctrl.h"
22 
23 #define STATE_MACHINE_DATA struct eap_sm
24 #define STATE_MACHINE_DEBUG_PREFIX "EAP"
25 
26 /* EAP state machines are described in RFC 4137 */
27 
28 static int eap_sm_calculateTimeout(struct eap_sm *sm, int retransCount,
29 				   int eapSRTT, int eapRTTVAR,
30 				   int methodTimeout);
31 static void eap_sm_parseEapResp(struct eap_sm *sm, const struct wpabuf *resp);
32 static int eap_sm_getId(const struct wpabuf *data);
33 static struct wpabuf * eap_sm_buildSuccess(struct eap_sm *sm, u8 id);
34 static struct wpabuf * eap_sm_buildFailure(struct eap_sm *sm, u8 id);
35 static int eap_sm_nextId(struct eap_sm *sm, int id);
36 static void eap_sm_Policy_update(struct eap_sm *sm, const u8 *nak_list,
37 				 size_t len);
38 static enum eap_type eap_sm_Policy_getNextMethod(struct eap_sm *sm,
39 						 int *vendor);
40 static int eap_sm_Policy_getDecision(struct eap_sm *sm);
41 static bool eap_sm_Policy_doPickUp(struct eap_sm *sm, enum eap_type method);
42 
43 
eap_get_erp_send_reauth_start(struct eap_sm * sm)44 static int eap_get_erp_send_reauth_start(struct eap_sm *sm)
45 {
46 	if (sm->eapol_cb->get_erp_send_reauth_start)
47 		return sm->eapol_cb->get_erp_send_reauth_start(sm->eapol_ctx);
48 	return 0;
49 }
50 
51 
eap_get_erp_domain(struct eap_sm * sm)52 static const char * eap_get_erp_domain(struct eap_sm *sm)
53 {
54 	if (sm->eapol_cb->get_erp_domain)
55 		return sm->eapol_cb->get_erp_domain(sm->eapol_ctx);
56 	return NULL;
57 }
58 
59 
60 #ifdef CONFIG_ERP
61 
eap_erp_get_key(struct eap_sm * sm,const char * keyname)62 static struct eap_server_erp_key * eap_erp_get_key(struct eap_sm *sm,
63 						   const char *keyname)
64 {
65 	if (sm->eapol_cb->erp_get_key)
66 		return sm->eapol_cb->erp_get_key(sm->eapol_ctx, keyname);
67 	return NULL;
68 }
69 
70 
eap_erp_add_key(struct eap_sm * sm,struct eap_server_erp_key * erp)71 static int eap_erp_add_key(struct eap_sm *sm, struct eap_server_erp_key *erp)
72 {
73 	if (sm->eapol_cb->erp_add_key)
74 		return sm->eapol_cb->erp_add_key(sm->eapol_ctx, erp);
75 	return -1;
76 }
77 
78 #endif /* CONFIG_ERP */
79 
80 
eap_sm_buildInitiateReauthStart(struct eap_sm * sm,u8 id)81 static struct wpabuf * eap_sm_buildInitiateReauthStart(struct eap_sm *sm,
82 						       u8 id)
83 {
84 	const char *domain;
85 	size_t plen = 1;
86 	struct wpabuf *msg;
87 	size_t domain_len = 0;
88 
89 	domain = eap_get_erp_domain(sm);
90 	if (domain) {
91 		domain_len = os_strlen(domain);
92 		plen += 2 + domain_len;
93 	}
94 
95 	msg = eap_msg_alloc(EAP_VENDOR_IETF,
96 			    (enum eap_type) EAP_ERP_TYPE_REAUTH_START, plen,
97 			    EAP_CODE_INITIATE, id);
98 	if (msg == NULL)
99 		return NULL;
100 	wpabuf_put_u8(msg, 0); /* Reserved */
101 	if (domain) {
102 		/* Domain name TLV */
103 		wpabuf_put_u8(msg, EAP_ERP_TLV_DOMAIN_NAME);
104 		wpabuf_put_u8(msg, domain_len);
105 		wpabuf_put_data(msg, domain, domain_len);
106 	}
107 
108 	return msg;
109 }
110 
111 
eap_copy_buf(struct wpabuf ** dst,const struct wpabuf * src)112 static int eap_copy_buf(struct wpabuf **dst, const struct wpabuf *src)
113 {
114 	if (src == NULL)
115 		return -1;
116 
117 	wpabuf_free(*dst);
118 	*dst = wpabuf_dup(src);
119 	return *dst ? 0 : -1;
120 }
121 
122 
eap_copy_data(u8 ** dst,size_t * dst_len,const u8 * src,size_t src_len)123 static int eap_copy_data(u8 **dst, size_t *dst_len,
124 			 const u8 *src, size_t src_len)
125 {
126 	if (src == NULL)
127 		return -1;
128 
129 	os_free(*dst);
130 	*dst = os_malloc(src_len);
131 	if (*dst) {
132 		os_memcpy(*dst, src, src_len);
133 		*dst_len = src_len;
134 		return 0;
135 	} else {
136 		*dst_len = 0;
137 		return -1;
138 	}
139 }
140 
141 #define EAP_COPY(dst, src) \
142 	eap_copy_data((dst), (dst ## Len), (src), (src ## Len))
143 
144 
145 /**
146  * eap_user_get - Fetch user information from the database
147  * @sm: Pointer to EAP state machine allocated with eap_server_sm_init()
148  * @identity: Identity (User-Name) of the user
149  * @identity_len: Length of identity in bytes
150  * @phase2: 0 = EAP phase1 user, 1 = EAP phase2 (tunneled) user
151  * Returns: 0 on success, or -1 on failure
152  *
153  * This function is used to fetch user information for EAP. The user will be
154  * selected based on the specified identity. sm->user and
155  * sm->user_eap_method_index are updated for the new user when a matching user
156  * is found. sm->user can be used to get user information (e.g., password).
157  */
eap_user_get(struct eap_sm * sm,const u8 * identity,size_t identity_len,int phase2)158 int eap_user_get(struct eap_sm *sm, const u8 *identity, size_t identity_len,
159 		 int phase2)
160 {
161 	struct eap_user *user;
162 
163 	if (sm == NULL || sm->eapol_cb == NULL ||
164 	    sm->eapol_cb->get_eap_user == NULL)
165 		return -1;
166 
167 	eap_user_free(sm->user);
168 	sm->user = NULL;
169 
170 	user = os_zalloc(sizeof(*user));
171 	if (user == NULL)
172 	    return -1;
173 
174 	if (sm->eapol_cb->get_eap_user(sm->eapol_ctx, identity,
175 				       identity_len, phase2, user) != 0) {
176 		eap_user_free(user);
177 		return -1;
178 	}
179 
180 	sm->user = user;
181 	sm->user_eap_method_index = 0;
182 
183 	return 0;
184 }
185 
186 
eap_log_msg(struct eap_sm * sm,const char * fmt,...)187 void eap_log_msg(struct eap_sm *sm, const char *fmt, ...)
188 {
189 	va_list ap;
190 	char *buf;
191 	int buflen;
192 
193 	if (sm == NULL || sm->eapol_cb == NULL || sm->eapol_cb->log_msg == NULL)
194 		return;
195 
196 	va_start(ap, fmt);
197 	buflen = vsnprintf(NULL, 0, fmt, ap) + 1;
198 	va_end(ap);
199 
200 	buf = os_malloc(buflen);
201 	if (buf == NULL)
202 		return;
203 	va_start(ap, fmt);
204 	vsnprintf(buf, buflen, fmt, ap);
205 	va_end(ap);
206 
207 	sm->eapol_cb->log_msg(sm->eapol_ctx, buf);
208 
209 	os_free(buf);
210 }
211 
212 
SM_STATE(EAP,DISABLED)213 SM_STATE(EAP, DISABLED)
214 {
215 	SM_ENTRY(EAP, DISABLED);
216 	sm->num_rounds = 0;
217 	sm->num_rounds_short = 0;
218 }
219 
220 
SM_STATE(EAP,INITIALIZE)221 SM_STATE(EAP, INITIALIZE)
222 {
223 	SM_ENTRY(EAP, INITIALIZE);
224 
225 	if (sm->eap_if.eapRestart && !sm->cfg->eap_server && sm->identity) {
226 		/*
227 		 * Need to allow internal Identity method to be used instead
228 		 * of passthrough at the beginning of reauthentication.
229 		 */
230 		eap_server_clear_identity(sm);
231 	}
232 
233 	sm->try_initiate_reauth = false;
234 	sm->currentId = -1;
235 	sm->eap_if.eapSuccess = false;
236 	sm->eap_if.eapFail = false;
237 	sm->eap_if.eapTimeout = false;
238 	bin_clear_free(sm->eap_if.eapKeyData, sm->eap_if.eapKeyDataLen);
239 	sm->eap_if.eapKeyData = NULL;
240 	sm->eap_if.eapKeyDataLen = 0;
241 	os_free(sm->eap_if.eapSessionId);
242 	sm->eap_if.eapSessionId = NULL;
243 	sm->eap_if.eapSessionIdLen = 0;
244 	sm->eap_if.eapKeyAvailable = false;
245 	sm->eap_if.eapRestart = false;
246 
247 	/*
248 	 * This is not defined in RFC 4137, but method state needs to be
249 	 * reseted here so that it does not remain in success state when
250 	 * re-authentication starts.
251 	 */
252 	if (sm->m && sm->eap_method_priv) {
253 		sm->m->reset(sm, sm->eap_method_priv);
254 		sm->eap_method_priv = NULL;
255 	}
256 	sm->m = NULL;
257 	sm->user_eap_method_index = 0;
258 
259 	if (sm->cfg->backend_auth) {
260 		sm->currentMethod = EAP_TYPE_NONE;
261 		/* parse rxResp, respId, respMethod */
262 		eap_sm_parseEapResp(sm, sm->eap_if.eapRespData);
263 		if (sm->rxResp) {
264 			sm->currentId = sm->respId;
265 		}
266 	}
267 	sm->num_rounds = 0;
268 	sm->num_rounds_short = 0;
269 	sm->method_pending = METHOD_PENDING_NONE;
270 
271 	wpa_msg(sm->cfg->msg_ctx, MSG_INFO, WPA_EVENT_EAP_STARTED
272 		MACSTR, MAC2STR(sm->peer_addr));
273 }
274 
275 
SM_STATE(EAP,PICK_UP_METHOD)276 SM_STATE(EAP, PICK_UP_METHOD)
277 {
278 	SM_ENTRY(EAP, PICK_UP_METHOD);
279 
280 	if (eap_sm_Policy_doPickUp(sm, sm->respMethod)) {
281 		sm->currentMethod = sm->respMethod;
282 		if (sm->m && sm->eap_method_priv) {
283 			sm->m->reset(sm, sm->eap_method_priv);
284 			sm->eap_method_priv = NULL;
285 		}
286 		sm->m = eap_server_get_eap_method(EAP_VENDOR_IETF,
287 						  sm->currentMethod);
288 		if (sm->m && sm->m->initPickUp) {
289 			sm->eap_method_priv = sm->m->initPickUp(sm);
290 			if (sm->eap_method_priv == NULL) {
291 				wpa_printf(MSG_DEBUG, "EAP: Failed to "
292 					   "initialize EAP method %d",
293 					   sm->currentMethod);
294 				sm->m = NULL;
295 				sm->currentMethod = EAP_TYPE_NONE;
296 			}
297 		} else {
298 			sm->m = NULL;
299 			sm->currentMethod = EAP_TYPE_NONE;
300 		}
301 	}
302 
303 	wpa_msg(sm->cfg->msg_ctx, MSG_INFO, WPA_EVENT_EAP_PROPOSED_METHOD
304 		"method=%u", sm->currentMethod);
305 }
306 
307 
SM_STATE(EAP,IDLE)308 SM_STATE(EAP, IDLE)
309 {
310 	SM_ENTRY(EAP, IDLE);
311 
312 	sm->eap_if.retransWhile = eap_sm_calculateTimeout(
313 		sm, sm->retransCount, sm->eap_if.eapSRTT, sm->eap_if.eapRTTVAR,
314 		sm->methodTimeout);
315 }
316 
317 
SM_STATE(EAP,RETRANSMIT)318 SM_STATE(EAP, RETRANSMIT)
319 {
320 	SM_ENTRY(EAP, RETRANSMIT);
321 
322 	sm->retransCount++;
323 	if (sm->retransCount <= sm->MaxRetrans && sm->lastReqData) {
324 		if (eap_copy_buf(&sm->eap_if.eapReqData, sm->lastReqData) == 0)
325 			sm->eap_if.eapReq = true;
326 	}
327 
328 	wpa_msg(sm->cfg->msg_ctx, MSG_INFO, WPA_EVENT_EAP_RETRANSMIT MACSTR,
329 		MAC2STR(sm->peer_addr));
330 }
331 
332 
SM_STATE(EAP,RECEIVED)333 SM_STATE(EAP, RECEIVED)
334 {
335 	SM_ENTRY(EAP, RECEIVED);
336 
337 	/* parse rxResp, respId, respMethod */
338 	eap_sm_parseEapResp(sm, sm->eap_if.eapRespData);
339 	sm->num_rounds++;
340 	if (!sm->eap_if.eapRespData || wpabuf_len(sm->eap_if.eapRespData) < 20)
341 		sm->num_rounds_short++;
342 	else
343 		sm->num_rounds_short = 0;
344 }
345 
346 
SM_STATE(EAP,DISCARD)347 SM_STATE(EAP, DISCARD)
348 {
349 	SM_ENTRY(EAP, DISCARD);
350 	sm->eap_if.eapResp = false;
351 	sm->eap_if.eapNoReq = true;
352 }
353 
354 
SM_STATE(EAP,SEND_REQUEST)355 SM_STATE(EAP, SEND_REQUEST)
356 {
357 	SM_ENTRY(EAP, SEND_REQUEST);
358 
359 	sm->retransCount = 0;
360 	if (sm->eap_if.eapReqData) {
361 		if (wpabuf_len(sm->eap_if.eapReqData) >= 20)
362 			sm->num_rounds_short = 0;
363 		if (eap_copy_buf(&sm->lastReqData, sm->eap_if.eapReqData) == 0)
364 		{
365 			sm->eap_if.eapResp = false;
366 			sm->eap_if.eapReq = true;
367 		} else {
368 			sm->eap_if.eapResp = false;
369 			sm->eap_if.eapReq = false;
370 		}
371 	} else {
372 		wpa_printf(MSG_INFO, "EAP: SEND_REQUEST - no eapReqData");
373 		sm->eap_if.eapResp = false;
374 		sm->eap_if.eapReq = false;
375 		sm->eap_if.eapNoReq = true;
376 	}
377 }
378 
379 
SM_STATE(EAP,INTEGRITY_CHECK)380 SM_STATE(EAP, INTEGRITY_CHECK)
381 {
382 	SM_ENTRY(EAP, INTEGRITY_CHECK);
383 
384 	if (!eap_hdr_len_valid(sm->eap_if.eapRespData, 1)) {
385 		sm->ignore = true;
386 		return;
387 	}
388 
389 	if (sm->m->check) {
390 		sm->ignore = sm->m->check(sm, sm->eap_method_priv,
391 					  sm->eap_if.eapRespData);
392 	}
393 }
394 
395 
SM_STATE(EAP,METHOD_REQUEST)396 SM_STATE(EAP, METHOD_REQUEST)
397 {
398 	SM_ENTRY(EAP, METHOD_REQUEST);
399 
400 	if (sm->m == NULL) {
401 		wpa_printf(MSG_DEBUG, "EAP: method not initialized");
402 		return;
403 	}
404 
405 	sm->currentId = eap_sm_nextId(sm, sm->currentId);
406 	wpa_printf(MSG_DEBUG, "EAP: building EAP-Request: Identifier %d",
407 		   sm->currentId);
408 	sm->lastId = sm->currentId;
409 	wpabuf_free(sm->eap_if.eapReqData);
410 	sm->eap_if.eapReqData = sm->m->buildReq(sm, sm->eap_method_priv,
411 						sm->currentId);
412 	if (sm->m->getTimeout)
413 		sm->methodTimeout = sm->m->getTimeout(sm, sm->eap_method_priv);
414 	else
415 		sm->methodTimeout = 0;
416 }
417 
418 
eap_server_erp_init(struct eap_sm * sm)419 static void eap_server_erp_init(struct eap_sm *sm)
420 {
421 #ifdef CONFIG_ERP
422 	u8 *emsk = NULL;
423 	size_t emsk_len = 0;
424 	u8 EMSKname[EAP_EMSK_NAME_LEN];
425 	u8 len[2], ctx[3];
426 	const char *domain;
427 	size_t domain_len, nai_buf_len;
428 	struct eap_server_erp_key *erp = NULL;
429 	int pos;
430 
431 	domain = eap_get_erp_domain(sm);
432 	if (!domain)
433 		return;
434 
435 	domain_len = os_strlen(domain);
436 
437 	nai_buf_len = 2 * EAP_EMSK_NAME_LEN + 1 + domain_len;
438 	if (nai_buf_len > 253) {
439 		/*
440 		 * keyName-NAI has a maximum length of 253 octet to fit in
441 		 * RADIUS attributes.
442 		 */
443 		wpa_printf(MSG_DEBUG,
444 			   "EAP: Too long realm for ERP keyName-NAI maximum length");
445 		return;
446 	}
447 	nai_buf_len++; /* null termination */
448 	erp = os_zalloc(sizeof(*erp) + nai_buf_len);
449 	if (erp == NULL)
450 		goto fail;
451 	erp->recv_seq = (u32) -1;
452 
453 	emsk = sm->m->get_emsk(sm, sm->eap_method_priv, &emsk_len);
454 	if (!emsk || emsk_len == 0 || emsk_len > ERP_MAX_KEY_LEN) {
455 		wpa_printf(MSG_DEBUG,
456 			   "EAP: No suitable EMSK available for ERP");
457 		goto fail;
458 	}
459 
460 	wpa_hexdump_key(MSG_DEBUG, "EAP: EMSK", emsk, emsk_len);
461 
462 	WPA_PUT_BE16(len, EAP_EMSK_NAME_LEN);
463 	if (hmac_sha256_kdf(sm->eap_if.eapSessionId, sm->eap_if.eapSessionIdLen,
464 			    "EMSK", len, sizeof(len),
465 			    EMSKname, EAP_EMSK_NAME_LEN) < 0) {
466 		wpa_printf(MSG_DEBUG, "EAP: Could not derive EMSKname");
467 		goto fail;
468 	}
469 	wpa_hexdump(MSG_DEBUG, "EAP: EMSKname", EMSKname, EAP_EMSK_NAME_LEN);
470 
471 	pos = wpa_snprintf_hex(erp->keyname_nai, nai_buf_len,
472 			       EMSKname, EAP_EMSK_NAME_LEN);
473 	erp->keyname_nai[pos] = '@';
474 	os_memcpy(&erp->keyname_nai[pos + 1], domain, domain_len);
475 
476 	WPA_PUT_BE16(len, emsk_len);
477 	if (hmac_sha256_kdf(emsk, emsk_len,
478 			    "EAP Re-authentication Root Key@ietf.org",
479 			    len, sizeof(len), erp->rRK, emsk_len) < 0) {
480 		wpa_printf(MSG_DEBUG, "EAP: Could not derive rRK for ERP");
481 		goto fail;
482 	}
483 	erp->rRK_len = emsk_len;
484 	wpa_hexdump_key(MSG_DEBUG, "EAP: ERP rRK", erp->rRK, erp->rRK_len);
485 
486 	ctx[0] = EAP_ERP_CS_HMAC_SHA256_128;
487 	WPA_PUT_BE16(&ctx[1], erp->rRK_len);
488 	if (hmac_sha256_kdf(erp->rRK, erp->rRK_len,
489 			    "Re-authentication Integrity Key@ietf.org",
490 			    ctx, sizeof(ctx), erp->rIK, erp->rRK_len) < 0) {
491 		wpa_printf(MSG_DEBUG, "EAP: Could not derive rIK for ERP");
492 		goto fail;
493 	}
494 	erp->rIK_len = erp->rRK_len;
495 	wpa_hexdump_key(MSG_DEBUG, "EAP: ERP rIK", erp->rIK, erp->rIK_len);
496 
497 	if (eap_erp_add_key(sm, erp) == 0) {
498 		wpa_printf(MSG_DEBUG, "EAP: Stored ERP keys %s",
499 			   erp->keyname_nai);
500 		erp = NULL;
501 	}
502 
503 fail:
504 	bin_clear_free(emsk, emsk_len);
505 	bin_clear_free(erp, sizeof(*erp));
506 #endif /* CONFIG_ERP */
507 }
508 
509 
SM_STATE(EAP,METHOD_RESPONSE)510 SM_STATE(EAP, METHOD_RESPONSE)
511 {
512 	SM_ENTRY(EAP, METHOD_RESPONSE);
513 
514 	if (!eap_hdr_len_valid(sm->eap_if.eapRespData, 1))
515 		return;
516 
517 	sm->m->process(sm, sm->eap_method_priv, sm->eap_if.eapRespData);
518 	if (sm->m->isDone(sm, sm->eap_method_priv)) {
519 		eap_sm_Policy_update(sm, NULL, 0);
520 		bin_clear_free(sm->eap_if.eapKeyData, sm->eap_if.eapKeyDataLen);
521 		if (sm->m->getKey) {
522 			sm->eap_if.eapKeyData = sm->m->getKey(
523 				sm, sm->eap_method_priv,
524 				&sm->eap_if.eapKeyDataLen);
525 		} else {
526 			sm->eap_if.eapKeyData = NULL;
527 			sm->eap_if.eapKeyDataLen = 0;
528 		}
529 		os_free(sm->eap_if.eapSessionId);
530 		sm->eap_if.eapSessionId = NULL;
531 		if (sm->m->getSessionId) {
532 			sm->eap_if.eapSessionId = sm->m->getSessionId(
533 				sm, sm->eap_method_priv,
534 				&sm->eap_if.eapSessionIdLen);
535 			wpa_hexdump(MSG_DEBUG, "EAP: Session-Id",
536 				    sm->eap_if.eapSessionId,
537 				    sm->eap_if.eapSessionIdLen);
538 		}
539 		if (sm->cfg->erp && sm->m->get_emsk && sm->eap_if.eapSessionId)
540 			eap_server_erp_init(sm);
541 		sm->methodState = METHOD_END;
542 	} else {
543 		sm->methodState = METHOD_CONTINUE;
544 	}
545 }
546 
547 
SM_STATE(EAP,PROPOSE_METHOD)548 SM_STATE(EAP, PROPOSE_METHOD)
549 {
550 	int vendor;
551 	enum eap_type type;
552 
553 	SM_ENTRY(EAP, PROPOSE_METHOD);
554 
555 	sm->try_initiate_reauth = false;
556 try_another_method:
557 	type = eap_sm_Policy_getNextMethod(sm, &vendor);
558 	if (vendor == EAP_VENDOR_IETF)
559 		sm->currentMethod = type;
560 	else
561 		sm->currentMethod = EAP_TYPE_EXPANDED;
562 	if (sm->m && sm->eap_method_priv) {
563 		sm->m->reset(sm, sm->eap_method_priv);
564 		sm->eap_method_priv = NULL;
565 	}
566 	sm->m = eap_server_get_eap_method(vendor, type);
567 	if (sm->m) {
568 		sm->eap_method_priv = sm->m->init(sm);
569 		if (sm->eap_method_priv == NULL) {
570 			wpa_printf(MSG_DEBUG, "EAP: Failed to initialize EAP "
571 				   "method %d", sm->currentMethod);
572 			sm->m = NULL;
573 			sm->currentMethod = EAP_TYPE_NONE;
574 			goto try_another_method;
575 		}
576 	}
577 	if (sm->m == NULL) {
578 		wpa_printf(MSG_DEBUG, "EAP: Could not find suitable EAP method");
579 		eap_log_msg(sm, "Could not find suitable EAP method");
580 		sm->decision = DECISION_FAILURE;
581 		return;
582 	}
583 	if (sm->currentMethod == EAP_TYPE_IDENTITY ||
584 	    sm->currentMethod == EAP_TYPE_NOTIFICATION)
585 		sm->methodState = METHOD_CONTINUE;
586 	else
587 		sm->methodState = METHOD_PROPOSED;
588 
589 	wpa_msg(sm->cfg->msg_ctx, MSG_INFO, WPA_EVENT_EAP_PROPOSED_METHOD
590 		"vendor=%u method=%u", vendor, sm->currentMethod);
591 	eap_log_msg(sm, "Propose EAP method vendor=%u method=%u",
592 		    vendor, sm->currentMethod);
593 }
594 
595 
SM_STATE(EAP,NAK)596 SM_STATE(EAP, NAK)
597 {
598 	const struct eap_hdr *nak;
599 	size_t len = 0;
600 	const u8 *pos;
601 	const u8 *nak_list = NULL;
602 
603 	SM_ENTRY(EAP, NAK);
604 
605 	if (sm->eap_method_priv) {
606 		sm->m->reset(sm, sm->eap_method_priv);
607 		sm->eap_method_priv = NULL;
608 	}
609 	sm->m = NULL;
610 
611 	if (!eap_hdr_len_valid(sm->eap_if.eapRespData, 1))
612 		return;
613 
614 	nak = wpabuf_head(sm->eap_if.eapRespData);
615 	if (nak && wpabuf_len(sm->eap_if.eapRespData) > sizeof(*nak)) {
616 		len = be_to_host16(nak->length);
617 		if (len > wpabuf_len(sm->eap_if.eapRespData))
618 			len = wpabuf_len(sm->eap_if.eapRespData);
619 		pos = (const u8 *) (nak + 1);
620 		len -= sizeof(*nak);
621 		if (*pos == EAP_TYPE_NAK) {
622 			pos++;
623 			len--;
624 			nak_list = pos;
625 		}
626 	}
627 	eap_sm_Policy_update(sm, nak_list, len);
628 }
629 
630 
SM_STATE(EAP,SELECT_ACTION)631 SM_STATE(EAP, SELECT_ACTION)
632 {
633 	SM_ENTRY(EAP, SELECT_ACTION);
634 
635 	sm->decision = eap_sm_Policy_getDecision(sm);
636 }
637 
638 
SM_STATE(EAP,TIMEOUT_FAILURE)639 SM_STATE(EAP, TIMEOUT_FAILURE)
640 {
641 	SM_ENTRY(EAP, TIMEOUT_FAILURE);
642 
643 	sm->eap_if.eapTimeout = true;
644 
645 	wpa_msg(sm->cfg->msg_ctx, MSG_INFO,
646 		WPA_EVENT_EAP_TIMEOUT_FAILURE MACSTR, MAC2STR(sm->peer_addr));
647 }
648 
649 
SM_STATE(EAP,FAILURE)650 SM_STATE(EAP, FAILURE)
651 {
652 	SM_ENTRY(EAP, FAILURE);
653 
654 	wpabuf_free(sm->eap_if.eapReqData);
655 	sm->eap_if.eapReqData = eap_sm_buildFailure(sm, sm->currentId);
656 	wpabuf_free(sm->lastReqData);
657 	sm->lastReqData = NULL;
658 	sm->eap_if.eapFail = true;
659 
660 	wpa_msg(sm->cfg->msg_ctx, MSG_INFO, WPA_EVENT_EAP_FAILURE
661 		MACSTR, MAC2STR(sm->peer_addr));
662 }
663 
664 
SM_STATE(EAP,SUCCESS)665 SM_STATE(EAP, SUCCESS)
666 {
667 	SM_ENTRY(EAP, SUCCESS);
668 
669 	wpabuf_free(sm->eap_if.eapReqData);
670 	sm->eap_if.eapReqData = eap_sm_buildSuccess(sm, sm->currentId);
671 	wpabuf_free(sm->lastReqData);
672 	sm->lastReqData = NULL;
673 	if (sm->eap_if.eapKeyData)
674 		sm->eap_if.eapKeyAvailable = true;
675 	sm->eap_if.eapSuccess = true;
676 
677 	wpa_msg(sm->cfg->msg_ctx, MSG_INFO, WPA_EVENT_EAP_SUCCESS
678 		MACSTR, MAC2STR(sm->peer_addr));
679 }
680 
681 
SM_STATE(EAP,INITIATE_REAUTH_START)682 SM_STATE(EAP, INITIATE_REAUTH_START)
683 {
684 	SM_ENTRY(EAP, INITIATE_REAUTH_START);
685 
686 	sm->initiate_reauth_start_sent = true;
687 	sm->try_initiate_reauth = true;
688 	sm->currentId = eap_sm_nextId(sm, sm->currentId);
689 	wpa_printf(MSG_DEBUG,
690 		   "EAP: building EAP-Initiate-Re-auth-Start: Identifier %d",
691 		   sm->currentId);
692 	sm->lastId = sm->currentId;
693 	wpabuf_free(sm->eap_if.eapReqData);
694 	sm->eap_if.eapReqData = eap_sm_buildInitiateReauthStart(sm,
695 								sm->currentId);
696 	wpabuf_free(sm->lastReqData);
697 	sm->lastReqData = NULL;
698 }
699 
700 
701 #ifdef CONFIG_ERP
702 
erp_send_finish_reauth(struct eap_sm * sm,struct eap_server_erp_key * erp,u8 id,u8 flags,u16 seq,const char * nai)703 static void erp_send_finish_reauth(struct eap_sm *sm,
704 				   struct eap_server_erp_key *erp, u8 id,
705 				   u8 flags, u16 seq, const char *nai)
706 {
707 	size_t plen;
708 	struct wpabuf *msg;
709 	u8 hash[SHA256_MAC_LEN];
710 	size_t hash_len;
711 	u8 seed[4];
712 
713 	if (erp) {
714 		switch (erp->cryptosuite) {
715 		case EAP_ERP_CS_HMAC_SHA256_256:
716 			hash_len = 32;
717 			break;
718 		case EAP_ERP_CS_HMAC_SHA256_128:
719 			hash_len = 16;
720 			break;
721 		default:
722 			return;
723 		}
724 	} else
725 		hash_len = 0;
726 
727 	plen = 1 + 2 + 2 + os_strlen(nai);
728 	if (hash_len)
729 		plen += 1 + hash_len;
730 	msg = eap_msg_alloc(EAP_VENDOR_IETF,
731 			    (enum eap_type) EAP_ERP_TYPE_REAUTH,
732 			    plen, EAP_CODE_FINISH, id);
733 	if (msg == NULL)
734 		return;
735 	wpabuf_put_u8(msg, flags);
736 	wpabuf_put_be16(msg, seq);
737 
738 	wpabuf_put_u8(msg, EAP_ERP_TLV_KEYNAME_NAI);
739 	wpabuf_put_u8(msg, os_strlen(nai));
740 	wpabuf_put_str(msg, nai);
741 
742 	if (erp) {
743 		wpabuf_put_u8(msg, erp->cryptosuite);
744 		if (hmac_sha256(erp->rIK, erp->rIK_len,
745 				wpabuf_head(msg), wpabuf_len(msg), hash) < 0) {
746 			wpabuf_free(msg);
747 			return;
748 		}
749 		wpabuf_put_data(msg, hash, hash_len);
750 	}
751 
752 	wpa_printf(MSG_DEBUG, "EAP: Send EAP-Finish/Re-auth (%s)",
753 		   flags & 0x80 ? "failure" : "success");
754 
755 	sm->lastId = sm->currentId;
756 	sm->currentId = id;
757 	wpabuf_free(sm->eap_if.eapReqData);
758 	sm->eap_if.eapReqData = msg;
759 	wpabuf_free(sm->lastReqData);
760 	sm->lastReqData = NULL;
761 
762 	if ((flags & 0x80) || !erp) {
763 		sm->eap_if.eapFail = true;
764 		wpa_msg(sm->cfg->msg_ctx, MSG_INFO, WPA_EVENT_EAP_FAILURE
765 			MACSTR, MAC2STR(sm->peer_addr));
766 		return;
767 	}
768 
769 	bin_clear_free(sm->eap_if.eapKeyData, sm->eap_if.eapKeyDataLen);
770 	sm->eap_if.eapKeyDataLen = 0;
771 	sm->eap_if.eapKeyData = os_malloc(erp->rRK_len);
772 	if (!sm->eap_if.eapKeyData)
773 		return;
774 
775 	WPA_PUT_BE16(seed, seq);
776 	WPA_PUT_BE16(&seed[2], erp->rRK_len);
777 	if (hmac_sha256_kdf(erp->rRK, erp->rRK_len,
778 			    "Re-authentication Master Session Key@ietf.org",
779 			    seed, sizeof(seed),
780 			    sm->eap_if.eapKeyData, erp->rRK_len) < 0) {
781 		wpa_printf(MSG_DEBUG, "EAP: Could not derive rMSK for ERP");
782 		bin_clear_free(sm->eap_if.eapKeyData, erp->rRK_len);
783 		sm->eap_if.eapKeyData = NULL;
784 		return;
785 	}
786 	sm->eap_if.eapKeyDataLen = erp->rRK_len;
787 	sm->eap_if.eapKeyAvailable = true;
788 	wpa_hexdump_key(MSG_DEBUG, "EAP: ERP rMSK",
789 			sm->eap_if.eapKeyData, sm->eap_if.eapKeyDataLen);
790 	sm->eap_if.eapSuccess = true;
791 
792 	wpa_msg(sm->cfg->msg_ctx, MSG_INFO, WPA_EVENT_EAP_SUCCESS
793 		MACSTR, MAC2STR(sm->peer_addr));
794 }
795 
796 
SM_STATE(EAP,INITIATE_RECEIVED)797 SM_STATE(EAP, INITIATE_RECEIVED)
798 {
799 	const u8 *pos, *end, *start, *tlvs, *hdr;
800 	const struct eap_hdr *ehdr;
801 	size_t len;
802 	u8 flags;
803 	u16 seq;
804 	char nai[254];
805 	struct eap_server_erp_key *erp;
806 	int max_len;
807 	u8 hash[SHA256_MAC_LEN];
808 	size_t hash_len;
809 	struct erp_tlvs parse;
810 	u8 resp_flags = 0x80; /* default to failure; cleared on success */
811 
812 	SM_ENTRY(EAP, INITIATE_RECEIVED);
813 
814 	sm->rxInitiate = false;
815 
816 	pos = eap_hdr_validate(EAP_VENDOR_IETF,
817 			       (enum eap_type) EAP_ERP_TYPE_REAUTH,
818 			       sm->eap_if.eapRespData, &len);
819 	if (pos == NULL) {
820 		wpa_printf(MSG_INFO, "EAP-Initiate: Invalid frame");
821 		goto fail;
822 	}
823 	hdr = wpabuf_head(sm->eap_if.eapRespData);
824 	ehdr = wpabuf_head(sm->eap_if.eapRespData);
825 
826 	wpa_hexdump(MSG_DEBUG, "EAP: EAP-Initiate/Re-Auth", pos, len);
827 	if (len < 4) {
828 		wpa_printf(MSG_INFO, "EAP: Too short EAP-Initiate/Re-auth");
829 		goto fail;
830 	}
831 	end = pos + len;
832 
833 	flags = *pos++;
834 	seq = WPA_GET_BE16(pos);
835 	pos += 2;
836 	wpa_printf(MSG_DEBUG, "EAP: Flags=0x%x SEQ=%u", flags, seq);
837 	tlvs = pos;
838 
839 	/*
840 	 * Parse TVs/TLVs. Since we do not yet know the length of the
841 	 * Authentication Tag, stop parsing if an unknown TV/TLV is seen and
842 	 * just try to find the keyName-NAI first so that we can check the
843 	 * Authentication Tag.
844 	 */
845 	if (erp_parse_tlvs(tlvs, end, &parse, 1) < 0)
846 		goto fail;
847 
848 	if (!parse.keyname) {
849 		wpa_printf(MSG_DEBUG,
850 			   "EAP: No keyName-NAI in EAP-Initiate/Re-auth Packet");
851 		goto fail;
852 	}
853 
854 	wpa_hexdump_ascii(MSG_DEBUG, "EAP: EAP-Initiate/Re-auth - keyName-NAI",
855 			  parse.keyname, parse.keyname_len);
856 	if (parse.keyname_len > 253) {
857 		wpa_printf(MSG_DEBUG,
858 			   "EAP: Too long keyName-NAI in EAP-Initiate/Re-auth");
859 		goto fail;
860 	}
861 	os_memcpy(nai, parse.keyname, parse.keyname_len);
862 	nai[parse.keyname_len] = '\0';
863 
864 	if (!sm->cfg->eap_server) {
865 		/*
866 		 * In passthrough case, EAP-Initiate/Re-auth replaces
867 		 * EAP Identity exchange. Use keyName-NAI as the user identity
868 		 * and forward EAP-Initiate/Re-auth to the backend
869 		 * authentication server.
870 		 */
871 		wpa_printf(MSG_DEBUG,
872 			   "EAP: Use keyName-NAI as user identity for backend authentication");
873 		eap_server_clear_identity(sm);
874 		sm->identity = (u8 *) dup_binstr(parse.keyname,
875 						 parse.keyname_len);
876 		if (!sm->identity)
877 			goto fail;
878 		sm->identity_len = parse.keyname_len;
879 		return;
880 	}
881 
882 	erp = eap_erp_get_key(sm, nai);
883 	if (!erp) {
884 		wpa_printf(MSG_DEBUG, "EAP: No matching ERP key found for %s",
885 			   nai);
886 		goto report_error;
887 	}
888 
889 	if (erp->recv_seq != (u32) -1 && erp->recv_seq >= seq) {
890 		wpa_printf(MSG_DEBUG,
891 			   "EAP: SEQ=%u replayed (already received SEQ=%u)",
892 			   seq, erp->recv_seq);
893 		goto fail;
894 	}
895 
896 	/* Is there enough room for Cryptosuite and Authentication Tag? */
897 	start = parse.keyname + parse.keyname_len;
898 	max_len = end - start;
899 	if (max_len <
900 	    1 + (erp->cryptosuite == EAP_ERP_CS_HMAC_SHA256_256 ? 32 : 16)) {
901 		wpa_printf(MSG_DEBUG,
902 			   "EAP: Not enough room for Authentication Tag");
903 		goto fail;
904 	}
905 
906 	switch (erp->cryptosuite) {
907 	case EAP_ERP_CS_HMAC_SHA256_256:
908 		if (end[-33] != erp->cryptosuite) {
909 			wpa_printf(MSG_DEBUG,
910 				   "EAP: Different Cryptosuite used");
911 			goto fail;
912 		}
913 		hash_len = 32;
914 		break;
915 	case EAP_ERP_CS_HMAC_SHA256_128:
916 		if (end[-17] != erp->cryptosuite) {
917 			wpa_printf(MSG_DEBUG,
918 				   "EAP: Different Cryptosuite used");
919 			goto fail;
920 		}
921 		hash_len = 16;
922 		break;
923 	default:
924 		hash_len = 0;
925 		break;
926 	}
927 
928 	if (hash_len) {
929 		if (hmac_sha256(erp->rIK, erp->rIK_len, hdr,
930 				end - hdr - hash_len, hash) < 0)
931 			goto fail;
932 		if (os_memcmp(end - hash_len, hash, hash_len) != 0) {
933 			wpa_printf(MSG_DEBUG,
934 				   "EAP: Authentication Tag mismatch");
935 			goto fail;
936 		}
937 	}
938 
939 	/* Check if any supported CS results in matching tag */
940 	if (!hash_len && max_len >= 1 + 32 &&
941 	    end[-33] == EAP_ERP_CS_HMAC_SHA256_256) {
942 		if (hmac_sha256(erp->rIK, erp->rIK_len, hdr,
943 				end - hdr - 32, hash) < 0)
944 			goto fail;
945 		if (os_memcmp(end - 32, hash, 32) == 0) {
946 			wpa_printf(MSG_DEBUG,
947 				   "EAP: Authentication Tag match using HMAC-SHA256-256");
948 			hash_len = 32;
949 			erp->cryptosuite = EAP_ERP_CS_HMAC_SHA256_256;
950 		}
951 	}
952 
953 	if (!hash_len && end[-17] == EAP_ERP_CS_HMAC_SHA256_128) {
954 		if (hmac_sha256(erp->rIK, erp->rIK_len, hdr,
955 				end - hdr - 16, hash) < 0)
956 			goto fail;
957 		if (os_memcmp(end - 16, hash, 16) == 0) {
958 			wpa_printf(MSG_DEBUG,
959 				   "EAP: Authentication Tag match using HMAC-SHA256-128");
960 			hash_len = 16;
961 			erp->cryptosuite = EAP_ERP_CS_HMAC_SHA256_128;
962 		}
963 	}
964 
965 	if (!hash_len) {
966 		wpa_printf(MSG_DEBUG,
967 			   "EAP: No supported cryptosuite matched Authentication Tag");
968 		goto fail;
969 	}
970 	end -= 1 + hash_len;
971 
972 	/*
973 	 * Parse TVs/TLVs again now that we know the exact part of the buffer
974 	 * that contains them.
975 	 */
976 	wpa_hexdump(MSG_DEBUG, "EAP: EAP-Initiate/Re-Auth TVs/TLVs",
977 		    tlvs, end - tlvs);
978 	if (erp_parse_tlvs(tlvs, end, &parse, 0) < 0)
979 		goto fail;
980 
981 	wpa_printf(MSG_DEBUG, "EAP: ERP key %s SEQ updated to %u",
982 		   erp->keyname_nai, seq);
983 	erp->recv_seq = seq;
984 	resp_flags &= ~0x80; /* R=0 - success */
985 
986 report_error:
987 	erp_send_finish_reauth(sm, erp, ehdr->identifier, resp_flags, seq, nai);
988 	return;
989 
990 fail:
991 	sm->ignore = true;
992 }
993 
994 #endif /* CONFIG_ERP */
995 
996 
SM_STATE(EAP,INITIALIZE_PASSTHROUGH)997 SM_STATE(EAP, INITIALIZE_PASSTHROUGH)
998 {
999 	SM_ENTRY(EAP, INITIALIZE_PASSTHROUGH);
1000 
1001 	wpabuf_free(sm->eap_if.aaaEapRespData);
1002 	sm->eap_if.aaaEapRespData = NULL;
1003 	sm->try_initiate_reauth = false;
1004 }
1005 
1006 
SM_STATE(EAP,IDLE2)1007 SM_STATE(EAP, IDLE2)
1008 {
1009 	SM_ENTRY(EAP, IDLE2);
1010 
1011 	sm->eap_if.retransWhile = eap_sm_calculateTimeout(
1012 		sm, sm->retransCount, sm->eap_if.eapSRTT, sm->eap_if.eapRTTVAR,
1013 		sm->methodTimeout);
1014 }
1015 
1016 
SM_STATE(EAP,RETRANSMIT2)1017 SM_STATE(EAP, RETRANSMIT2)
1018 {
1019 	SM_ENTRY(EAP, RETRANSMIT2);
1020 
1021 	sm->retransCount++;
1022 	if (sm->retransCount <= sm->MaxRetrans && sm->lastReqData) {
1023 		if (eap_copy_buf(&sm->eap_if.eapReqData, sm->lastReqData) == 0)
1024 			sm->eap_if.eapReq = true;
1025 	}
1026 
1027 	wpa_msg(sm->cfg->msg_ctx, MSG_INFO, WPA_EVENT_EAP_RETRANSMIT2 MACSTR,
1028 		MAC2STR(sm->peer_addr));
1029 }
1030 
1031 
SM_STATE(EAP,RECEIVED2)1032 SM_STATE(EAP, RECEIVED2)
1033 {
1034 	SM_ENTRY(EAP, RECEIVED2);
1035 
1036 	/* parse rxResp, respId, respMethod */
1037 	eap_sm_parseEapResp(sm, sm->eap_if.eapRespData);
1038 }
1039 
1040 
SM_STATE(EAP,DISCARD2)1041 SM_STATE(EAP, DISCARD2)
1042 {
1043 	SM_ENTRY(EAP, DISCARD2);
1044 	sm->eap_if.eapResp = false;
1045 	sm->eap_if.eapNoReq = true;
1046 }
1047 
1048 
SM_STATE(EAP,SEND_REQUEST2)1049 SM_STATE(EAP, SEND_REQUEST2)
1050 {
1051 	SM_ENTRY(EAP, SEND_REQUEST2);
1052 
1053 	sm->retransCount = 0;
1054 	if (sm->eap_if.eapReqData) {
1055 		if (eap_copy_buf(&sm->lastReqData, sm->eap_if.eapReqData) == 0)
1056 		{
1057 			sm->eap_if.eapResp = false;
1058 			sm->eap_if.eapReq = true;
1059 		} else {
1060 			sm->eap_if.eapResp = false;
1061 			sm->eap_if.eapReq = false;
1062 		}
1063 	} else {
1064 		wpa_printf(MSG_INFO, "EAP: SEND_REQUEST2 - no eapReqData");
1065 		sm->eap_if.eapResp = false;
1066 		sm->eap_if.eapReq = false;
1067 		sm->eap_if.eapNoReq = true;
1068 	}
1069 }
1070 
1071 
SM_STATE(EAP,AAA_REQUEST)1072 SM_STATE(EAP, AAA_REQUEST)
1073 {
1074 	SM_ENTRY(EAP, AAA_REQUEST);
1075 
1076 	if (sm->eap_if.eapRespData == NULL) {
1077 		wpa_printf(MSG_INFO, "EAP: AAA_REQUEST - no eapRespData");
1078 		return;
1079 	}
1080 
1081 	/*
1082 	 * if (respMethod == IDENTITY)
1083 	 *	aaaIdentity = eapRespData
1084 	 * This is already taken care of by the EAP-Identity method which
1085 	 * stores the identity into sm->identity.
1086 	 */
1087 
1088 	eap_copy_buf(&sm->eap_if.aaaEapRespData, sm->eap_if.eapRespData);
1089 }
1090 
1091 
SM_STATE(EAP,AAA_RESPONSE)1092 SM_STATE(EAP, AAA_RESPONSE)
1093 {
1094 	SM_ENTRY(EAP, AAA_RESPONSE);
1095 
1096 	eap_copy_buf(&sm->eap_if.eapReqData, sm->eap_if.aaaEapReqData);
1097 	sm->currentId = eap_sm_getId(sm->eap_if.eapReqData);
1098 	sm->methodTimeout = sm->eap_if.aaaMethodTimeout;
1099 }
1100 
1101 
SM_STATE(EAP,AAA_IDLE)1102 SM_STATE(EAP, AAA_IDLE)
1103 {
1104 	SM_ENTRY(EAP, AAA_IDLE);
1105 
1106 	sm->eap_if.aaaFail = false;
1107 	sm->eap_if.aaaSuccess = false;
1108 	sm->eap_if.aaaEapReq = false;
1109 	sm->eap_if.aaaEapNoReq = false;
1110 	sm->eap_if.aaaEapResp = true;
1111 }
1112 
1113 
SM_STATE(EAP,TIMEOUT_FAILURE2)1114 SM_STATE(EAP, TIMEOUT_FAILURE2)
1115 {
1116 	SM_ENTRY(EAP, TIMEOUT_FAILURE2);
1117 
1118 	sm->eap_if.eapTimeout = true;
1119 
1120 	wpa_msg(sm->cfg->msg_ctx, MSG_INFO,
1121 		WPA_EVENT_EAP_TIMEOUT_FAILURE2 MACSTR, MAC2STR(sm->peer_addr));
1122 }
1123 
1124 
SM_STATE(EAP,FAILURE2)1125 SM_STATE(EAP, FAILURE2)
1126 {
1127 	SM_ENTRY(EAP, FAILURE2);
1128 
1129 	eap_copy_buf(&sm->eap_if.eapReqData, sm->eap_if.aaaEapReqData);
1130 	sm->eap_if.eapFail = true;
1131 
1132 	wpa_msg(sm->cfg->msg_ctx, MSG_INFO, WPA_EVENT_EAP_FAILURE2 MACSTR,
1133 		MAC2STR(sm->peer_addr));
1134 }
1135 
1136 
SM_STATE(EAP,SUCCESS2)1137 SM_STATE(EAP, SUCCESS2)
1138 {
1139 	SM_ENTRY(EAP, SUCCESS2);
1140 
1141 	eap_copy_buf(&sm->eap_if.eapReqData, sm->eap_if.aaaEapReqData);
1142 
1143 	sm->eap_if.eapKeyAvailable = sm->eap_if.aaaEapKeyAvailable;
1144 	if (sm->eap_if.aaaEapKeyAvailable) {
1145 		EAP_COPY(&sm->eap_if.eapKeyData, sm->eap_if.aaaEapKeyData);
1146 	} else {
1147 		bin_clear_free(sm->eap_if.eapKeyData, sm->eap_if.eapKeyDataLen);
1148 		sm->eap_if.eapKeyData = NULL;
1149 		sm->eap_if.eapKeyDataLen = 0;
1150 	}
1151 
1152 	sm->eap_if.eapSuccess = true;
1153 
1154 	/*
1155 	 * Start reauthentication with identity request even though we know the
1156 	 * previously used identity. This is needed to get reauthentication
1157 	 * started properly.
1158 	 */
1159 	sm->start_reauth = true;
1160 
1161 	wpa_msg(sm->cfg->msg_ctx, MSG_INFO, WPA_EVENT_EAP_SUCCESS2 MACSTR,
1162 		MAC2STR(sm->peer_addr));
1163 }
1164 
1165 
SM_STEP(EAP)1166 SM_STEP(EAP)
1167 {
1168 	if (sm->eap_if.eapRestart && sm->eap_if.portEnabled)
1169 		SM_ENTER_GLOBAL(EAP, INITIALIZE);
1170 	else if (!sm->eap_if.portEnabled)
1171 		SM_ENTER_GLOBAL(EAP, DISABLED);
1172 	else if (sm->num_rounds > sm->cfg->max_auth_rounds) {
1173 		if (sm->num_rounds == sm->cfg->max_auth_rounds + 1) {
1174 			wpa_printf(MSG_DEBUG, "EAP: more than %d "
1175 				   "authentication rounds - abort",
1176 				   sm->cfg->max_auth_rounds);
1177 			sm->num_rounds++;
1178 			SM_ENTER_GLOBAL(EAP, FAILURE);
1179 		}
1180 	} else if (sm->num_rounds_short > sm->cfg->max_auth_rounds_short) {
1181 		if (sm->num_rounds_short ==
1182 		    sm->cfg->max_auth_rounds_short + 1) {
1183 			wpa_printf(MSG_DEBUG,
1184 				   "EAP: more than %d authentication rounds (short) - abort",
1185 				   sm->cfg->max_auth_rounds_short);
1186 			sm->num_rounds_short++;
1187 			SM_ENTER_GLOBAL(EAP, FAILURE);
1188 		}
1189 	} else switch (sm->EAP_state) {
1190 	case EAP_INITIALIZE:
1191 		if (sm->cfg->backend_auth) {
1192 			if (!sm->rxResp)
1193 				SM_ENTER(EAP, SELECT_ACTION);
1194 			else if (sm->rxResp &&
1195 				 (sm->respMethod == EAP_TYPE_NAK ||
1196 				  (sm->respMethod == EAP_TYPE_EXPANDED &&
1197 				   sm->respVendor == EAP_VENDOR_IETF &&
1198 				   sm->respVendorMethod == EAP_TYPE_NAK)))
1199 				SM_ENTER(EAP, NAK);
1200 			else
1201 				SM_ENTER(EAP, PICK_UP_METHOD);
1202 		} else {
1203 			SM_ENTER(EAP, SELECT_ACTION);
1204 		}
1205 		break;
1206 	case EAP_PICK_UP_METHOD:
1207 		if (sm->currentMethod == EAP_TYPE_NONE) {
1208 			SM_ENTER(EAP, SELECT_ACTION);
1209 		} else {
1210 			SM_ENTER(EAP, METHOD_RESPONSE);
1211 		}
1212 		break;
1213 	case EAP_DISABLED:
1214 		if (sm->eap_if.portEnabled)
1215 			SM_ENTER(EAP, INITIALIZE);
1216 		break;
1217 	case EAP_IDLE:
1218 		if (sm->eap_if.retransWhile == 0) {
1219 			if (sm->try_initiate_reauth) {
1220 				sm->try_initiate_reauth = false;
1221 				SM_ENTER(EAP, SELECT_ACTION);
1222 			} else {
1223 				SM_ENTER(EAP, RETRANSMIT);
1224 			}
1225 		} else if (sm->eap_if.eapResp)
1226 			SM_ENTER(EAP, RECEIVED);
1227 		break;
1228 	case EAP_RETRANSMIT:
1229 		if (sm->retransCount > sm->MaxRetrans)
1230 			SM_ENTER(EAP, TIMEOUT_FAILURE);
1231 		else
1232 			SM_ENTER(EAP, IDLE);
1233 		break;
1234 	case EAP_RECEIVED:
1235 		if (sm->rxResp && (sm->respId == sm->currentId) &&
1236 		    (sm->respMethod == EAP_TYPE_NAK ||
1237 		     (sm->respMethod == EAP_TYPE_EXPANDED &&
1238 		      sm->respVendor == EAP_VENDOR_IETF &&
1239 		      sm->respVendorMethod == EAP_TYPE_NAK))
1240 		    && (sm->methodState == METHOD_PROPOSED))
1241 			SM_ENTER(EAP, NAK);
1242 		else if (sm->rxResp && (sm->respId == sm->currentId) &&
1243 			 ((sm->respMethod == sm->currentMethod) ||
1244 			  (sm->respMethod == EAP_TYPE_EXPANDED &&
1245 			   sm->respVendor == EAP_VENDOR_IETF &&
1246 			   sm->respVendorMethod == sm->currentMethod)))
1247 			SM_ENTER(EAP, INTEGRITY_CHECK);
1248 #ifdef CONFIG_ERP
1249 		else if (sm->rxInitiate)
1250 			SM_ENTER(EAP, INITIATE_RECEIVED);
1251 #endif /* CONFIG_ERP */
1252 		else {
1253 			wpa_printf(MSG_DEBUG, "EAP: RECEIVED->DISCARD: "
1254 				   "rxResp=%d respId=%d currentId=%d "
1255 				   "respMethod=%d currentMethod=%d",
1256 				   sm->rxResp, sm->respId, sm->currentId,
1257 				   sm->respMethod, sm->currentMethod);
1258 			eap_log_msg(sm, "Discard received EAP message");
1259 			SM_ENTER(EAP, DISCARD);
1260 		}
1261 		break;
1262 	case EAP_DISCARD:
1263 		SM_ENTER(EAP, IDLE);
1264 		break;
1265 	case EAP_SEND_REQUEST:
1266 		SM_ENTER(EAP, IDLE);
1267 		break;
1268 	case EAP_INTEGRITY_CHECK:
1269 		if (sm->ignore)
1270 			SM_ENTER(EAP, DISCARD);
1271 		else
1272 			SM_ENTER(EAP, METHOD_RESPONSE);
1273 		break;
1274 	case EAP_METHOD_REQUEST:
1275 		if (sm->m == NULL) {
1276 			/*
1277 			 * This transition is not mentioned in RFC 4137, but it
1278 			 * is needed to handle cleanly a case where EAP method
1279 			 * initialization fails.
1280 			 */
1281 			SM_ENTER(EAP, FAILURE);
1282 			break;
1283 		}
1284 		SM_ENTER(EAP, SEND_REQUEST);
1285 		if (sm->eap_if.eapNoReq && !sm->eap_if.eapReq) {
1286 			/*
1287 			 * This transition is not mentioned in RFC 4137, but it
1288 			 * is needed to handle cleanly a case where EAP method
1289 			 * buildReq fails.
1290 			 */
1291 			wpa_printf(MSG_DEBUG,
1292 				   "EAP: Method did not return a request");
1293 			SM_ENTER(EAP, FAILURE);
1294 			break;
1295 		}
1296 		break;
1297 	case EAP_METHOD_RESPONSE:
1298 		/*
1299 		 * Note: Mechanism to allow EAP methods to wait while going
1300 		 * through pending processing is an extension to RFC 4137
1301 		 * which only defines the transits to SELECT_ACTION and
1302 		 * METHOD_REQUEST from this METHOD_RESPONSE state.
1303 		 */
1304 		if (sm->methodState == METHOD_END)
1305 			SM_ENTER(EAP, SELECT_ACTION);
1306 		else if (sm->method_pending == METHOD_PENDING_WAIT) {
1307 			wpa_printf(MSG_DEBUG, "EAP: Method has pending "
1308 				   "processing - wait before proceeding to "
1309 				   "METHOD_REQUEST state");
1310 		} else if (sm->method_pending == METHOD_PENDING_CONT) {
1311 			wpa_printf(MSG_DEBUG, "EAP: Method has completed "
1312 				   "pending processing - reprocess pending "
1313 				   "EAP message");
1314 			sm->method_pending = METHOD_PENDING_NONE;
1315 			SM_ENTER(EAP, METHOD_RESPONSE);
1316 		} else
1317 			SM_ENTER(EAP, METHOD_REQUEST);
1318 		break;
1319 	case EAP_PROPOSE_METHOD:
1320 		/*
1321 		 * Note: Mechanism to allow EAP methods to wait while going
1322 		 * through pending processing is an extension to RFC 4137
1323 		 * which only defines the transit to METHOD_REQUEST from this
1324 		 * PROPOSE_METHOD state.
1325 		 */
1326 		if (sm->method_pending == METHOD_PENDING_WAIT) {
1327 			wpa_printf(MSG_DEBUG, "EAP: Method has pending "
1328 				   "processing - wait before proceeding to "
1329 				   "METHOD_REQUEST state");
1330 			if (sm->user_eap_method_index > 0)
1331 				sm->user_eap_method_index--;
1332 		} else if (sm->method_pending == METHOD_PENDING_CONT) {
1333 			wpa_printf(MSG_DEBUG, "EAP: Method has completed "
1334 				   "pending processing - reprocess pending "
1335 				   "EAP message");
1336 			sm->method_pending = METHOD_PENDING_NONE;
1337 			SM_ENTER(EAP, PROPOSE_METHOD);
1338 		} else
1339 			SM_ENTER(EAP, METHOD_REQUEST);
1340 		break;
1341 	case EAP_NAK:
1342 		SM_ENTER(EAP, SELECT_ACTION);
1343 		break;
1344 	case EAP_SELECT_ACTION:
1345 		if (sm->decision == DECISION_FAILURE)
1346 			SM_ENTER(EAP, FAILURE);
1347 		else if (sm->decision == DECISION_SUCCESS)
1348 			SM_ENTER(EAP, SUCCESS);
1349 		else if (sm->decision == DECISION_PASSTHROUGH)
1350 			SM_ENTER(EAP, INITIALIZE_PASSTHROUGH);
1351 		else if (sm->decision == DECISION_INITIATE_REAUTH_START)
1352 			SM_ENTER(EAP, INITIATE_REAUTH_START);
1353 #ifdef CONFIG_ERP
1354 		else if (sm->cfg->eap_server && sm->cfg->erp && sm->rxInitiate)
1355 			SM_ENTER(EAP, INITIATE_RECEIVED);
1356 #endif /* CONFIG_ERP */
1357 		else
1358 			SM_ENTER(EAP, PROPOSE_METHOD);
1359 		break;
1360 	case EAP_INITIATE_REAUTH_START:
1361 		SM_ENTER(EAP, SEND_REQUEST);
1362 		break;
1363 	case EAP_INITIATE_RECEIVED:
1364 		if (!sm->cfg->eap_server)
1365 			SM_ENTER(EAP, SELECT_ACTION);
1366 		break;
1367 	case EAP_TIMEOUT_FAILURE:
1368 		break;
1369 	case EAP_FAILURE:
1370 		break;
1371 	case EAP_SUCCESS:
1372 		break;
1373 
1374 	case EAP_INITIALIZE_PASSTHROUGH:
1375 		if (sm->currentId == -1)
1376 			SM_ENTER(EAP, AAA_IDLE);
1377 		else
1378 			SM_ENTER(EAP, AAA_REQUEST);
1379 		break;
1380 	case EAP_IDLE2:
1381 		if (sm->eap_if.eapResp)
1382 			SM_ENTER(EAP, RECEIVED2);
1383 		else if (sm->eap_if.retransWhile == 0)
1384 			SM_ENTER(EAP, RETRANSMIT2);
1385 		break;
1386 	case EAP_RETRANSMIT2:
1387 		if (sm->retransCount > sm->MaxRetrans)
1388 			SM_ENTER(EAP, TIMEOUT_FAILURE2);
1389 		else
1390 			SM_ENTER(EAP, IDLE2);
1391 		break;
1392 	case EAP_RECEIVED2:
1393 		if (sm->rxResp && (sm->respId == sm->currentId))
1394 			SM_ENTER(EAP, AAA_REQUEST);
1395 		else
1396 			SM_ENTER(EAP, DISCARD2);
1397 		break;
1398 	case EAP_DISCARD2:
1399 		SM_ENTER(EAP, IDLE2);
1400 		break;
1401 	case EAP_SEND_REQUEST2:
1402 		SM_ENTER(EAP, IDLE2);
1403 		break;
1404 	case EAP_AAA_REQUEST:
1405 		SM_ENTER(EAP, AAA_IDLE);
1406 		break;
1407 	case EAP_AAA_RESPONSE:
1408 		SM_ENTER(EAP, SEND_REQUEST2);
1409 		break;
1410 	case EAP_AAA_IDLE:
1411 		if (sm->eap_if.aaaFail)
1412 			SM_ENTER(EAP, FAILURE2);
1413 		else if (sm->eap_if.aaaSuccess)
1414 			SM_ENTER(EAP, SUCCESS2);
1415 		else if (sm->eap_if.aaaEapReq)
1416 			SM_ENTER(EAP, AAA_RESPONSE);
1417 		else if (sm->eap_if.aaaTimeout)
1418 			SM_ENTER(EAP, TIMEOUT_FAILURE2);
1419 		break;
1420 	case EAP_TIMEOUT_FAILURE2:
1421 		break;
1422 	case EAP_FAILURE2:
1423 		break;
1424 	case EAP_SUCCESS2:
1425 		break;
1426 	}
1427 }
1428 
1429 
eap_sm_calculateTimeout(struct eap_sm * sm,int retransCount,int eapSRTT,int eapRTTVAR,int methodTimeout)1430 static int eap_sm_calculateTimeout(struct eap_sm *sm, int retransCount,
1431 				   int eapSRTT, int eapRTTVAR,
1432 				   int methodTimeout)
1433 {
1434 	int rto, i;
1435 
1436 	if (sm->try_initiate_reauth) {
1437 		wpa_printf(MSG_DEBUG,
1438 			   "EAP: retransmit timeout 1 second for EAP-Initiate-Re-auth-Start");
1439 		return 1;
1440 	}
1441 
1442 	if (methodTimeout) {
1443 		/*
1444 		 * EAP method (either internal or through AAA server, provided
1445 		 * timeout hint. Use that as-is as a timeout for retransmitting
1446 		 * the EAP request if no response is received.
1447 		 */
1448 		wpa_printf(MSG_DEBUG, "EAP: retransmit timeout %d seconds "
1449 			   "(from EAP method hint)", methodTimeout);
1450 		return methodTimeout;
1451 	}
1452 
1453 	/*
1454 	 * RFC 3748 recommends algorithms described in RFC 2988 for estimation
1455 	 * of the retransmission timeout. This should be implemented once
1456 	 * round-trip time measurements are available. For nowm a simple
1457 	 * backoff mechanism is used instead if there are no EAP method
1458 	 * specific hints.
1459 	 *
1460 	 * SRTT = smoothed round-trip time
1461 	 * RTTVAR = round-trip time variation
1462 	 * RTO = retransmission timeout
1463 	 */
1464 
1465 	/*
1466 	 * RFC 2988, 2.1: before RTT measurement, set RTO to 3 seconds for
1467 	 * initial retransmission and then double the RTO to provide back off
1468 	 * per 5.5. Limit the maximum RTO to 20 seconds per RFC 3748, 4.3
1469 	 * modified RTOmax.
1470 	 */
1471 	rto = 3;
1472 	for (i = 0; i < retransCount; i++) {
1473 		rto *= 2;
1474 		if (rto >= 20) {
1475 			rto = 20;
1476 			break;
1477 		}
1478 	}
1479 
1480 	wpa_printf(MSG_DEBUG, "EAP: retransmit timeout %d seconds "
1481 		   "(from dynamic back off; retransCount=%d)",
1482 		   rto, retransCount);
1483 
1484 	return rto;
1485 }
1486 
1487 
eap_sm_parseEapResp(struct eap_sm * sm,const struct wpabuf * resp)1488 static void eap_sm_parseEapResp(struct eap_sm *sm, const struct wpabuf *resp)
1489 {
1490 	const struct eap_hdr *hdr;
1491 	size_t plen;
1492 
1493 	/* parse rxResp, respId, respMethod */
1494 	sm->rxResp = false;
1495 	sm->rxInitiate = false;
1496 	sm->respId = -1;
1497 	sm->respMethod = EAP_TYPE_NONE;
1498 	sm->respVendor = EAP_VENDOR_IETF;
1499 	sm->respVendorMethod = EAP_TYPE_NONE;
1500 
1501 	if (resp == NULL || wpabuf_len(resp) < sizeof(*hdr)) {
1502 		wpa_printf(MSG_DEBUG, "EAP: parseEapResp: invalid resp=%p "
1503 			   "len=%lu", resp,
1504 			   resp ? (unsigned long) wpabuf_len(resp) : 0);
1505 		return;
1506 	}
1507 
1508 	hdr = wpabuf_head(resp);
1509 	plen = be_to_host16(hdr->length);
1510 	if (plen > wpabuf_len(resp)) {
1511 		wpa_printf(MSG_DEBUG, "EAP: Ignored truncated EAP-Packet "
1512 			   "(len=%lu plen=%lu)",
1513 			   (unsigned long) wpabuf_len(resp),
1514 			   (unsigned long) plen);
1515 		return;
1516 	}
1517 
1518 	sm->respId = hdr->identifier;
1519 
1520 	if (hdr->code == EAP_CODE_RESPONSE)
1521 		sm->rxResp = true;
1522 	else if (hdr->code == EAP_CODE_INITIATE)
1523 		sm->rxInitiate = true;
1524 
1525 	if (plen > sizeof(*hdr)) {
1526 		u8 *pos = (u8 *) (hdr + 1);
1527 		sm->respMethod = *pos++;
1528 		if (sm->respMethod == EAP_TYPE_EXPANDED) {
1529 			if (plen < sizeof(*hdr) + 8) {
1530 				wpa_printf(MSG_DEBUG, "EAP: Ignored truncated "
1531 					   "expanded EAP-Packet (plen=%lu)",
1532 					   (unsigned long) plen);
1533 				return;
1534 			}
1535 			sm->respVendor = WPA_GET_BE24(pos);
1536 			pos += 3;
1537 			sm->respVendorMethod = WPA_GET_BE32(pos);
1538 		}
1539 	}
1540 
1541 	wpa_printf(MSG_DEBUG,
1542 		   "EAP: parseEapResp: rxResp=%d rxInitiate=%d respId=%d respMethod=%u respVendor=%u respVendorMethod=%u",
1543 		   sm->rxResp, sm->rxInitiate, sm->respId, sm->respMethod,
1544 		   sm->respVendor, sm->respVendorMethod);
1545 }
1546 
1547 
eap_sm_getId(const struct wpabuf * data)1548 static int eap_sm_getId(const struct wpabuf *data)
1549 {
1550 	const struct eap_hdr *hdr;
1551 
1552 	if (data == NULL || wpabuf_len(data) < sizeof(*hdr))
1553 		return -1;
1554 
1555 	hdr = wpabuf_head(data);
1556 	wpa_printf(MSG_DEBUG, "EAP: getId: id=%d", hdr->identifier);
1557 	return hdr->identifier;
1558 }
1559 
1560 
eap_sm_buildSuccess(struct eap_sm * sm,u8 id)1561 static struct wpabuf * eap_sm_buildSuccess(struct eap_sm *sm, u8 id)
1562 {
1563 	struct wpabuf *msg;
1564 	struct eap_hdr *resp;
1565 	wpa_printf(MSG_DEBUG, "EAP: Building EAP-Success (id=%d)", id);
1566 
1567 	msg = wpabuf_alloc(sizeof(*resp));
1568 	if (msg == NULL)
1569 		return NULL;
1570 	resp = wpabuf_put(msg, sizeof(*resp));
1571 	resp->code = EAP_CODE_SUCCESS;
1572 	resp->identifier = id;
1573 	resp->length = host_to_be16(sizeof(*resp));
1574 
1575 	return msg;
1576 }
1577 
1578 
eap_sm_buildFailure(struct eap_sm * sm,u8 id)1579 static struct wpabuf * eap_sm_buildFailure(struct eap_sm *sm, u8 id)
1580 {
1581 	struct wpabuf *msg;
1582 	struct eap_hdr *resp;
1583 	wpa_printf(MSG_DEBUG, "EAP: Building EAP-Failure (id=%d)", id);
1584 
1585 	msg = wpabuf_alloc(sizeof(*resp));
1586 	if (msg == NULL)
1587 		return NULL;
1588 	resp = wpabuf_put(msg, sizeof(*resp));
1589 	resp->code = EAP_CODE_FAILURE;
1590 	resp->identifier = id;
1591 	resp->length = host_to_be16(sizeof(*resp));
1592 
1593 	return msg;
1594 }
1595 
1596 
eap_sm_nextId(struct eap_sm * sm,int id)1597 static int eap_sm_nextId(struct eap_sm *sm, int id)
1598 {
1599 	if (id < 0) {
1600 		/* RFC 3748 Ch 4.1: recommended to initialize Identifier with a
1601 		 * random number */
1602 		id = rand() & 0xff;
1603 		if (id != sm->lastId)
1604 			return id;
1605 	}
1606 	return (id + 1) & 0xff;
1607 }
1608 
1609 
1610 /**
1611  * eap_sm_process_nak - Process EAP-Response/Nak
1612  * @sm: Pointer to EAP state machine allocated with eap_server_sm_init()
1613  * @nak_list: Nak list (allowed methods) from the supplicant
1614  * @len: Length of nak_list in bytes
1615  *
1616  * This function is called when EAP-Response/Nak is received from the
1617  * supplicant. This can happen for both phase 1 and phase 2 authentications.
1618  */
eap_sm_process_nak(struct eap_sm * sm,const u8 * nak_list,size_t len)1619 void eap_sm_process_nak(struct eap_sm *sm, const u8 *nak_list, size_t len)
1620 {
1621 	int i;
1622 	size_t j;
1623 
1624 	if (sm->user == NULL)
1625 		return;
1626 
1627 	wpa_printf(MSG_MSGDUMP, "EAP: processing NAK (current EAP method "
1628 		   "index %d)", sm->user_eap_method_index);
1629 
1630 	wpa_hexdump(MSG_MSGDUMP, "EAP: configured methods",
1631 		    (u8 *) sm->user->methods,
1632 		    EAP_MAX_METHODS * sizeof(sm->user->methods[0]));
1633 	wpa_hexdump(MSG_MSGDUMP, "EAP: list of methods supported by the peer",
1634 		    nak_list, len);
1635 
1636 	i = sm->user_eap_method_index;
1637 	while (i < EAP_MAX_METHODS &&
1638 	       (sm->user->methods[i].vendor != EAP_VENDOR_IETF ||
1639 		sm->user->methods[i].method != EAP_TYPE_NONE)) {
1640 		if (sm->user->methods[i].vendor != EAP_VENDOR_IETF)
1641 			goto not_found;
1642 		for (j = 0; j < len; j++) {
1643 			if (nak_list[j] == sm->user->methods[i].method) {
1644 				break;
1645 			}
1646 		}
1647 
1648 		if (j < len) {
1649 			/* found */
1650 			i++;
1651 			continue;
1652 		}
1653 
1654 	not_found:
1655 		/* not found - remove from the list */
1656 		if (i + 1 < EAP_MAX_METHODS) {
1657 			os_memmove(&sm->user->methods[i],
1658 				   &sm->user->methods[i + 1],
1659 				   (EAP_MAX_METHODS - i - 1) *
1660 				   sizeof(sm->user->methods[0]));
1661 		}
1662 		sm->user->methods[EAP_MAX_METHODS - 1].vendor =
1663 			EAP_VENDOR_IETF;
1664 		sm->user->methods[EAP_MAX_METHODS - 1].method = EAP_TYPE_NONE;
1665 	}
1666 
1667 	wpa_hexdump(MSG_MSGDUMP, "EAP: new list of configured methods",
1668 		    (u8 *) sm->user->methods, EAP_MAX_METHODS *
1669 		    sizeof(sm->user->methods[0]));
1670 }
1671 
1672 
eap_sm_Policy_update(struct eap_sm * sm,const u8 * nak_list,size_t len)1673 static void eap_sm_Policy_update(struct eap_sm *sm, const u8 *nak_list,
1674 				 size_t len)
1675 {
1676 	if (nak_list == NULL || sm == NULL || sm->user == NULL)
1677 		return;
1678 
1679 	if (sm->user->phase2) {
1680 		wpa_printf(MSG_DEBUG, "EAP: EAP-Nak received after Phase2 user"
1681 			   " info was selected - reject");
1682 		sm->decision = DECISION_FAILURE;
1683 		return;
1684 	}
1685 
1686 	eap_sm_process_nak(sm, nak_list, len);
1687 }
1688 
1689 
eap_sm_Policy_getNextMethod(struct eap_sm * sm,int * vendor)1690 static enum eap_type eap_sm_Policy_getNextMethod(struct eap_sm *sm, int *vendor)
1691 {
1692 	enum eap_type next;
1693 	int idx = sm->user_eap_method_index;
1694 
1695 	/* In theory, there should be no problems with starting
1696 	 * re-authentication with something else than EAP-Request/Identity and
1697 	 * this does indeed work with wpa_supplicant. However, at least Funk
1698 	 * Supplicant seemed to ignore re-auth if it skipped
1699 	 * EAP-Request/Identity.
1700 	 * Re-auth sets currentId == -1, so that can be used here to select
1701 	 * whether Identity needs to be requested again. */
1702 	if (sm->identity == NULL || sm->currentId == -1) {
1703 		*vendor = EAP_VENDOR_IETF;
1704 		next = EAP_TYPE_IDENTITY;
1705 		sm->update_user = true;
1706 	} else if (sm->user && idx < EAP_MAX_METHODS &&
1707 		   (sm->user->methods[idx].vendor != EAP_VENDOR_IETF ||
1708 		    sm->user->methods[idx].method != EAP_TYPE_NONE)) {
1709 		*vendor = sm->user->methods[idx].vendor;
1710 		next = sm->user->methods[idx].method;
1711 		sm->user_eap_method_index++;
1712 	} else {
1713 		*vendor = EAP_VENDOR_IETF;
1714 		next = EAP_TYPE_NONE;
1715 	}
1716 	wpa_printf(MSG_DEBUG, "EAP: getNextMethod: vendor %d type %d",
1717 		   *vendor, next);
1718 	return next;
1719 }
1720 
1721 
eap_sm_Policy_getDecision(struct eap_sm * sm)1722 static int eap_sm_Policy_getDecision(struct eap_sm *sm)
1723 {
1724 	if (!sm->cfg->eap_server && sm->identity && !sm->start_reauth) {
1725 		wpa_printf(MSG_DEBUG, "EAP: getDecision: -> PASSTHROUGH");
1726 		return DECISION_PASSTHROUGH;
1727 	}
1728 
1729 	if (sm->m && sm->currentMethod != EAP_TYPE_IDENTITY &&
1730 	    sm->m->isSuccess(sm, sm->eap_method_priv)) {
1731 		wpa_printf(MSG_DEBUG, "EAP: getDecision: method succeeded -> "
1732 			   "SUCCESS");
1733 		sm->update_user = true;
1734 		return DECISION_SUCCESS;
1735 	}
1736 
1737 	if (sm->m && sm->m->isDone(sm, sm->eap_method_priv) &&
1738 	    !sm->m->isSuccess(sm, sm->eap_method_priv)) {
1739 		wpa_printf(MSG_DEBUG, "EAP: getDecision: method failed -> "
1740 			   "FAILURE");
1741 		sm->update_user = true;
1742 		return DECISION_FAILURE;
1743 	}
1744 
1745 	if ((sm->user == NULL || sm->update_user) && sm->identity &&
1746 	    !sm->start_reauth) {
1747 		/*
1748 		 * Allow Identity method to be started once to allow identity
1749 		 * selection hint to be sent from the authentication server,
1750 		 * but prevent a loop of Identity requests by only allowing
1751 		 * this to happen once.
1752 		 */
1753 		int id_req = 0;
1754 		if (sm->user && sm->currentMethod == EAP_TYPE_IDENTITY &&
1755 		    sm->user->methods[0].vendor == EAP_VENDOR_IETF &&
1756 		    sm->user->methods[0].method == EAP_TYPE_IDENTITY)
1757 			id_req = 1;
1758 		if (eap_user_get(sm, sm->identity, sm->identity_len, 0) != 0) {
1759 			wpa_printf(MSG_DEBUG, "EAP: getDecision: user not "
1760 				   "found from database -> FAILURE");
1761 			return DECISION_FAILURE;
1762 		}
1763 		if (id_req && sm->user &&
1764 		    sm->user->methods[0].vendor == EAP_VENDOR_IETF &&
1765 		    sm->user->methods[0].method == EAP_TYPE_IDENTITY) {
1766 			wpa_printf(MSG_DEBUG, "EAP: getDecision: stop "
1767 				   "identity request loop -> FAILURE");
1768 			sm->update_user = true;
1769 			return DECISION_FAILURE;
1770 		}
1771 		sm->update_user = false;
1772 	}
1773 	sm->start_reauth = false;
1774 
1775 	if (sm->user && sm->user_eap_method_index < EAP_MAX_METHODS &&
1776 	    (sm->user->methods[sm->user_eap_method_index].vendor !=
1777 	     EAP_VENDOR_IETF ||
1778 	     sm->user->methods[sm->user_eap_method_index].method !=
1779 	     EAP_TYPE_NONE)) {
1780 		wpa_printf(MSG_DEBUG, "EAP: getDecision: another method "
1781 			   "available -> CONTINUE");
1782 		return DECISION_CONTINUE;
1783 	}
1784 
1785 	if (!sm->identity && eap_get_erp_send_reauth_start(sm) &&
1786 	    !sm->initiate_reauth_start_sent) {
1787 		wpa_printf(MSG_DEBUG,
1788 			   "EAP: getDecision: send EAP-Initiate/Re-auth-Start");
1789 		return DECISION_INITIATE_REAUTH_START;
1790 	}
1791 
1792 	if (sm->identity == NULL || sm->currentId == -1) {
1793 		wpa_printf(MSG_DEBUG, "EAP: getDecision: no identity known "
1794 			   "yet -> CONTINUE");
1795 		return DECISION_CONTINUE;
1796 	}
1797 
1798 	wpa_printf(MSG_DEBUG, "EAP: getDecision: no more methods available -> "
1799 		   "FAILURE");
1800 	return DECISION_FAILURE;
1801 }
1802 
1803 
eap_sm_Policy_doPickUp(struct eap_sm * sm,enum eap_type method)1804 static bool eap_sm_Policy_doPickUp(struct eap_sm *sm, enum eap_type method)
1805 {
1806 	return method == EAP_TYPE_IDENTITY;
1807 }
1808 
1809 
1810 /**
1811  * eap_server_sm_step - Step EAP server state machine
1812  * @sm: Pointer to EAP state machine allocated with eap_server_sm_init()
1813  * Returns: 1 if EAP state was changed or 0 if not
1814  *
1815  * This function advances EAP state machine to a new state to match with the
1816  * current variables. This should be called whenever variables used by the EAP
1817  * state machine have changed.
1818  */
eap_server_sm_step(struct eap_sm * sm)1819 int eap_server_sm_step(struct eap_sm *sm)
1820 {
1821 	int res = 0;
1822 	do {
1823 		sm->changed = false;
1824 		SM_STEP_RUN(EAP);
1825 		if (sm->changed)
1826 			res = 1;
1827 	} while (sm->changed);
1828 	return res;
1829 }
1830 
1831 
eap_user_free(struct eap_user * user)1832 void eap_user_free(struct eap_user *user)
1833 {
1834 	if (user == NULL)
1835 		return;
1836 	bin_clear_free(user->password, user->password_len);
1837 	user->password = NULL;
1838 	bin_clear_free(user->salt, user->salt_len);
1839 	user->salt = NULL;
1840 	os_free(user);
1841 }
1842 
1843 
1844 /**
1845  * eap_server_sm_init - Allocate and initialize EAP server state machine
1846  * @eapol_ctx: Context data to be used with eapol_cb calls
1847  * @eapol_cb: Pointer to EAPOL callback functions
1848  * @conf: EAP configuration
1849  * Returns: Pointer to the allocated EAP state machine or %NULL on failure
1850  *
1851  * This function allocates and initializes an EAP state machine.
1852  */
eap_server_sm_init(void * eapol_ctx,const struct eapol_callbacks * eapol_cb,const struct eap_config * conf,const struct eap_session_data * sess)1853 struct eap_sm * eap_server_sm_init(void *eapol_ctx,
1854 				   const struct eapol_callbacks *eapol_cb,
1855 				   const struct eap_config *conf,
1856 				   const struct eap_session_data *sess)
1857 {
1858 	struct eap_sm *sm;
1859 
1860 	sm = os_zalloc(sizeof(*sm));
1861 	if (sm == NULL)
1862 		return NULL;
1863 	sm->eapol_ctx = eapol_ctx;
1864 	sm->eapol_cb = eapol_cb;
1865 	sm->MaxRetrans = 5; /* RFC 3748: max 3-5 retransmissions suggested */
1866 	sm->cfg = conf;
1867 	if (sess->assoc_wps_ie)
1868 		sm->assoc_wps_ie = wpabuf_dup(sess->assoc_wps_ie);
1869 	if (sess->assoc_p2p_ie)
1870 		sm->assoc_p2p_ie = wpabuf_dup(sess->assoc_p2p_ie);
1871 	if (sess->peer_addr)
1872 		os_memcpy(sm->peer_addr, sess->peer_addr, ETH_ALEN);
1873 #ifdef CONFIG_TESTING_OPTIONS
1874 	sm->tls_test_flags = sess->tls_test_flags;
1875 #endif /* CONFIG_TESTING_OPTIONS */
1876 
1877 	wpa_printf(MSG_DEBUG, "EAP: Server state machine created");
1878 
1879 	return sm;
1880 }
1881 
1882 
1883 /**
1884  * eap_server_sm_deinit - Deinitialize and free an EAP server state machine
1885  * @sm: Pointer to EAP state machine allocated with eap_server_sm_init()
1886  *
1887  * This function deinitializes EAP state machine and frees all allocated
1888  * resources.
1889  */
eap_server_sm_deinit(struct eap_sm * sm)1890 void eap_server_sm_deinit(struct eap_sm *sm)
1891 {
1892 	if (sm == NULL)
1893 		return;
1894 	wpa_printf(MSG_DEBUG, "EAP: Server state machine removed");
1895 	if (sm->m && sm->eap_method_priv)
1896 		sm->m->reset(sm, sm->eap_method_priv);
1897 	wpabuf_free(sm->eap_if.eapReqData);
1898 	bin_clear_free(sm->eap_if.eapKeyData, sm->eap_if.eapKeyDataLen);
1899 	os_free(sm->eap_if.eapSessionId);
1900 	wpabuf_free(sm->lastReqData);
1901 	wpabuf_free(sm->eap_if.eapRespData);
1902 	os_free(sm->identity);
1903 	os_free(sm->serial_num);
1904 	wpabuf_free(sm->eap_if.aaaEapReqData);
1905 	wpabuf_free(sm->eap_if.aaaEapRespData);
1906 	bin_clear_free(sm->eap_if.aaaEapKeyData, sm->eap_if.aaaEapKeyDataLen);
1907 	eap_user_free(sm->user);
1908 	wpabuf_free(sm->assoc_wps_ie);
1909 	wpabuf_free(sm->assoc_p2p_ie);
1910 	os_free(sm);
1911 }
1912 
1913 
1914 /**
1915  * eap_sm_notify_cached - Notify EAP state machine of cached PMK
1916  * @sm: Pointer to EAP state machine allocated with eap_server_sm_init()
1917  *
1918  * This function is called when PMKSA caching is used to skip EAP
1919  * authentication.
1920  */
eap_sm_notify_cached(struct eap_sm * sm)1921 void eap_sm_notify_cached(struct eap_sm *sm)
1922 {
1923 	if (sm == NULL)
1924 		return;
1925 
1926 	sm->EAP_state = EAP_SUCCESS;
1927 }
1928 
1929 
1930 /**
1931  * eap_sm_pending_cb - EAP state machine callback for a pending EAP request
1932  * @sm: Pointer to EAP state machine allocated with eap_server_sm_init()
1933  *
1934  * This function is called when data for a pending EAP-Request is received.
1935  */
eap_sm_pending_cb(struct eap_sm * sm)1936 void eap_sm_pending_cb(struct eap_sm *sm)
1937 {
1938 	if (sm == NULL)
1939 		return;
1940 	wpa_printf(MSG_DEBUG, "EAP: Callback for pending request received");
1941 	if (sm->method_pending == METHOD_PENDING_WAIT)
1942 		sm->method_pending = METHOD_PENDING_CONT;
1943 }
1944 
1945 
1946 /**
1947  * eap_sm_method_pending - Query whether EAP method is waiting for pending data
1948  * @sm: Pointer to EAP state machine allocated with eap_server_sm_init()
1949  * Returns: 1 if method is waiting for pending data or 0 if not
1950  */
eap_sm_method_pending(struct eap_sm * sm)1951 int eap_sm_method_pending(struct eap_sm *sm)
1952 {
1953 	if (sm == NULL)
1954 		return 0;
1955 	return sm->method_pending == METHOD_PENDING_WAIT;
1956 }
1957 
1958 
1959 /**
1960  * eap_get_identity - Get the user identity (from EAP-Response/Identity)
1961  * @sm: Pointer to EAP state machine allocated with eap_server_sm_init()
1962  * @len: Buffer for returning identity length
1963  * Returns: Pointer to the user identity or %NULL if not available
1964  */
eap_get_identity(struct eap_sm * sm,size_t * len)1965 const u8 * eap_get_identity(struct eap_sm *sm, size_t *len)
1966 {
1967 	*len = sm->identity_len;
1968 	return sm->identity;
1969 }
1970 
1971 
1972 /**
1973  * eap_get_serial_num - Get the serial number of user certificate
1974  * @sm: Pointer to EAP state machine allocated with eap_server_sm_init()
1975  * Returns: Pointer to the serial number or %NULL if not available
1976  */
eap_get_serial_num(struct eap_sm * sm)1977 const char * eap_get_serial_num(struct eap_sm *sm)
1978 {
1979 	return sm->serial_num;
1980 }
1981 
1982 
1983 /**
1984  * eap_get_method - Get the used EAP method
1985  * @sm: Pointer to EAP state machine allocated with eap_server_sm_init()
1986  * Returns: Pointer to the method name or %NULL if not available
1987  */
eap_get_method(struct eap_sm * sm)1988 const char * eap_get_method(struct eap_sm *sm)
1989 {
1990 	if (!sm || !sm->m)
1991 		return NULL;
1992 	return sm->m->name;
1993 }
1994 
1995 
1996 /**
1997  * eap_get_imsi - Get IMSI of the user
1998  * @sm: Pointer to EAP state machine allocated with eap_server_sm_init()
1999  * Returns: Pointer to IMSI or %NULL if not available
2000  */
eap_get_imsi(struct eap_sm * sm)2001 const char * eap_get_imsi(struct eap_sm *sm)
2002 {
2003 	if (!sm || sm->imsi[0] == '\0')
2004 		return NULL;
2005 	return sm->imsi;
2006 }
2007 
2008 
eap_erp_update_identity(struct eap_sm * sm,const u8 * eap,size_t len)2009 void eap_erp_update_identity(struct eap_sm *sm, const u8 *eap, size_t len)
2010 {
2011 #ifdef CONFIG_ERP
2012 	const struct eap_hdr *hdr;
2013 	const u8 *pos, *end;
2014 	struct erp_tlvs parse;
2015 
2016 	if (len < sizeof(*hdr) + 1)
2017 		return;
2018 	hdr = (const struct eap_hdr *) eap;
2019 	end = eap + len;
2020 	pos = (const u8 *) (hdr + 1);
2021 	if (hdr->code != EAP_CODE_INITIATE || *pos != EAP_ERP_TYPE_REAUTH)
2022 		return;
2023 	pos++;
2024 	if (pos + 3 > end)
2025 		return;
2026 
2027 	/* Skip Flags and SEQ */
2028 	pos += 3;
2029 
2030 	if (erp_parse_tlvs(pos, end, &parse, 1) < 0 || !parse.keyname)
2031 		return;
2032 	wpa_hexdump_ascii(MSG_DEBUG,
2033 			  "EAP: Update identity based on EAP-Initiate/Re-auth keyName-NAI",
2034 			  parse.keyname, parse.keyname_len);
2035 	os_free(sm->identity);
2036 	sm->identity = os_malloc(parse.keyname_len);
2037 	if (sm->identity) {
2038 		os_memcpy(sm->identity, parse.keyname, parse.keyname_len);
2039 		sm->identity_len = parse.keyname_len;
2040 	} else {
2041 		sm->identity_len = 0;
2042 	}
2043 #endif /* CONFIG_ERP */
2044 }
2045 
2046 
2047 /**
2048  * eap_get_interface - Get pointer to EAP-EAPOL interface data
2049  * @sm: Pointer to EAP state machine allocated with eap_server_sm_init()
2050  * Returns: Pointer to the EAP-EAPOL interface data
2051  */
eap_get_interface(struct eap_sm * sm)2052 struct eap_eapol_interface * eap_get_interface(struct eap_sm *sm)
2053 {
2054 	return &sm->eap_if;
2055 }
2056 
2057 
2058 /**
2059  * eap_server_clear_identity - Clear EAP identity information
2060  * @sm: Pointer to EAP state machine allocated with eap_server_sm_init()
2061  *
2062  * This function can be used to clear the EAP identity information in the EAP
2063  * server context. This allows the EAP/Identity method to be used again after
2064  * EAPOL-Start or EAPOL-Logoff.
2065  */
eap_server_clear_identity(struct eap_sm * sm)2066 void eap_server_clear_identity(struct eap_sm *sm)
2067 {
2068 	os_free(sm->identity);
2069 	sm->identity = NULL;
2070 }
2071 
2072 
2073 #ifdef CONFIG_TESTING_OPTIONS
eap_server_mschap_rx_callback(struct eap_sm * sm,const char * source,const u8 * username,size_t username_len,const u8 * challenge,const u8 * response)2074 void eap_server_mschap_rx_callback(struct eap_sm *sm, const char *source,
2075 				   const u8 *username, size_t username_len,
2076 				   const u8 *challenge, const u8 *response)
2077 {
2078 	char hex_challenge[30], hex_response[90], user[100];
2079 
2080 	/* Print out Challenge and Response in format supported by asleap. */
2081 	if (username)
2082 		printf_encode(user, sizeof(user), username, username_len);
2083 	else
2084 		user[0] = '\0';
2085 	wpa_snprintf_hex_sep(hex_challenge, sizeof(hex_challenge),
2086 			     challenge, sizeof(challenge), ':');
2087 	wpa_snprintf_hex_sep(hex_response, sizeof(hex_response), response, 24,
2088 			     ':');
2089 	wpa_printf(MSG_DEBUG, "[%s/user=%s] asleap -C %s -R %s",
2090 		   source, user, hex_challenge, hex_response);
2091 }
2092 #endif /* CONFIG_TESTING_OPTIONS */
2093 
2094 
eap_server_config_free(struct eap_config * cfg)2095 void eap_server_config_free(struct eap_config *cfg)
2096 {
2097 	if (!cfg)
2098 		return;
2099 	os_free(cfg->pac_opaque_encr_key);
2100 	os_free(cfg->eap_fast_a_id);
2101 	os_free(cfg->eap_fast_a_id_info);
2102 	os_free(cfg->server_id);
2103 	os_free(cfg);
2104 }
2105