wps_enrollee.c revision cf32e60fa7e0d33fe1551a6dba8dcbbec47ea50e
1/*
2 * Wi-Fi Protected Setup - Enrollee
3 * Copyright (c) 2008, Jouni Malinen <j@w1.fi>
4 *
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
7 */
8
9#include "includes.h"
10
11#include "common.h"
12#include "crypto/crypto.h"
13#include "crypto/sha256.h"
14#include "crypto/random.h"
15#include "wps_i.h"
16#include "wps_dev_attr.h"
17
18
19static int wps_build_wps_state(struct wps_data *wps, struct wpabuf *msg)
20{
21	u8 state;
22	if (wps->wps->ap)
23		state = wps->wps->wps_state;
24	else
25		state = WPS_STATE_NOT_CONFIGURED;
26	wpa_printf(MSG_DEBUG, "WPS:  * Wi-Fi Protected Setup State (%d)",
27		   state);
28	wpabuf_put_be16(msg, ATTR_WPS_STATE);
29	wpabuf_put_be16(msg, 1);
30	wpabuf_put_u8(msg, state);
31	return 0;
32}
33
34
35static int wps_build_e_hash(struct wps_data *wps, struct wpabuf *msg)
36{
37	u8 *hash;
38	const u8 *addr[4];
39	size_t len[4];
40
41	if (random_get_bytes(wps->snonce, 2 * WPS_SECRET_NONCE_LEN) < 0)
42		return -1;
43	wpa_hexdump(MSG_DEBUG, "WPS: E-S1", wps->snonce, WPS_SECRET_NONCE_LEN);
44	wpa_hexdump(MSG_DEBUG, "WPS: E-S2",
45		    wps->snonce + WPS_SECRET_NONCE_LEN, WPS_SECRET_NONCE_LEN);
46
47	if (wps->dh_pubkey_e == NULL || wps->dh_pubkey_r == NULL) {
48		wpa_printf(MSG_DEBUG, "WPS: DH public keys not available for "
49			   "E-Hash derivation");
50		return -1;
51	}
52
53	wpa_printf(MSG_DEBUG, "WPS:  * E-Hash1");
54	wpabuf_put_be16(msg, ATTR_E_HASH1);
55	wpabuf_put_be16(msg, SHA256_MAC_LEN);
56	hash = wpabuf_put(msg, SHA256_MAC_LEN);
57	/* E-Hash1 = HMAC_AuthKey(E-S1 || PSK1 || PK_E || PK_R) */
58	addr[0] = wps->snonce;
59	len[0] = WPS_SECRET_NONCE_LEN;
60	addr[1] = wps->psk1;
61	len[1] = WPS_PSK_LEN;
62	addr[2] = wpabuf_head(wps->dh_pubkey_e);
63	len[2] = wpabuf_len(wps->dh_pubkey_e);
64	addr[3] = wpabuf_head(wps->dh_pubkey_r);
65	len[3] = wpabuf_len(wps->dh_pubkey_r);
66	hmac_sha256_vector(wps->authkey, WPS_AUTHKEY_LEN, 4, addr, len, hash);
67	wpa_hexdump(MSG_DEBUG, "WPS: E-Hash1", hash, SHA256_MAC_LEN);
68
69	wpa_printf(MSG_DEBUG, "WPS:  * E-Hash2");
70	wpabuf_put_be16(msg, ATTR_E_HASH2);
71	wpabuf_put_be16(msg, SHA256_MAC_LEN);
72	hash = wpabuf_put(msg, SHA256_MAC_LEN);
73	/* E-Hash2 = HMAC_AuthKey(E-S2 || PSK2 || PK_E || PK_R) */
74	addr[0] = wps->snonce + WPS_SECRET_NONCE_LEN;
75	addr[1] = wps->psk2;
76	hmac_sha256_vector(wps->authkey, WPS_AUTHKEY_LEN, 4, addr, len, hash);
77	wpa_hexdump(MSG_DEBUG, "WPS: E-Hash2", hash, SHA256_MAC_LEN);
78
79	return 0;
80}
81
82
83static int wps_build_e_snonce1(struct wps_data *wps, struct wpabuf *msg)
84{
85	wpa_printf(MSG_DEBUG, "WPS:  * E-SNonce1");
86	wpabuf_put_be16(msg, ATTR_E_SNONCE1);
87	wpabuf_put_be16(msg, WPS_SECRET_NONCE_LEN);
88	wpabuf_put_data(msg, wps->snonce, WPS_SECRET_NONCE_LEN);
89	return 0;
90}
91
92
93static int wps_build_e_snonce2(struct wps_data *wps, struct wpabuf *msg)
94{
95	wpa_printf(MSG_DEBUG, "WPS:  * E-SNonce2");
96	wpabuf_put_be16(msg, ATTR_E_SNONCE2);
97	wpabuf_put_be16(msg, WPS_SECRET_NONCE_LEN);
98	wpabuf_put_data(msg, wps->snonce + WPS_SECRET_NONCE_LEN,
99			WPS_SECRET_NONCE_LEN);
100	return 0;
101}
102
103
104static struct wpabuf * wps_build_m1(struct wps_data *wps)
105{
106	struct wpabuf *msg;
107	u16 config_methods;
108
109	if (random_get_bytes(wps->nonce_e, WPS_NONCE_LEN) < 0)
110		return NULL;
111	wpa_hexdump(MSG_DEBUG, "WPS: Enrollee Nonce",
112		    wps->nonce_e, WPS_NONCE_LEN);
113
114	wpa_printf(MSG_DEBUG, "WPS: Building Message M1");
115	msg = wpabuf_alloc(1000);
116	if (msg == NULL)
117		return NULL;
118
119	config_methods = wps->wps->config_methods;
120	if (wps->wps->ap && !wps->pbc_in_m1 &&
121	    (wps->dev_password_len != 0 ||
122	     (config_methods & WPS_CONFIG_DISPLAY))) {
123		/*
124		 * These are the methods that the AP supports as an Enrollee
125		 * for adding external Registrars, so remove PushButton.
126		 *
127		 * As a workaround for Windows 7 mechanism for probing WPS
128		 * capabilities from M1, leave PushButton option if no PIN
129		 * method is available or if WPS configuration enables PBC
130		 * workaround.
131		 */
132		config_methods &= ~WPS_CONFIG_PUSHBUTTON;
133#ifdef CONFIG_WPS2
134		config_methods &= ~(WPS_CONFIG_VIRT_PUSHBUTTON |
135				    WPS_CONFIG_PHY_PUSHBUTTON);
136#endif /* CONFIG_WPS2 */
137	}
138
139	if (wps_build_version(msg) ||
140	    wps_build_msg_type(msg, WPS_M1) ||
141	    wps_build_uuid_e(msg, wps->uuid_e) ||
142	    wps_build_mac_addr(msg, wps->mac_addr_e) ||
143	    wps_build_enrollee_nonce(wps, msg) ||
144	    wps_build_public_key(wps, msg) ||
145	    wps_build_auth_type_flags(wps, msg) ||
146	    wps_build_encr_type_flags(wps, msg) ||
147	    wps_build_conn_type_flags(wps, msg) ||
148	    wps_build_config_methods(msg, config_methods) ||
149	    wps_build_wps_state(wps, msg) ||
150	    wps_build_device_attrs(&wps->wps->dev, msg) ||
151	    wps_build_rf_bands(&wps->wps->dev, msg,
152			       wps->wps->rf_band_cb(wps->wps->cb_ctx)) ||
153	    wps_build_assoc_state(wps, msg) ||
154	    wps_build_dev_password_id(msg, wps->dev_pw_id) ||
155	    wps_build_config_error(msg, WPS_CFG_NO_ERROR) ||
156	    wps_build_os_version(&wps->wps->dev, msg) ||
157	    wps_build_wfa_ext(msg, 0, NULL, 0) ||
158	    wps_build_vendor_ext_m1(&wps->wps->dev, msg)) {
159		wpabuf_free(msg);
160		return NULL;
161	}
162
163	wps->state = RECV_M2;
164	return msg;
165}
166
167
168static struct wpabuf * wps_build_m3(struct wps_data *wps)
169{
170	struct wpabuf *msg;
171
172	wpa_printf(MSG_DEBUG, "WPS: Building Message M3");
173
174	if (wps->dev_password == NULL) {
175		wpa_printf(MSG_DEBUG, "WPS: No Device Password available");
176		return NULL;
177	}
178	wps_derive_psk(wps, wps->dev_password, wps->dev_password_len);
179
180	msg = wpabuf_alloc(1000);
181	if (msg == NULL)
182		return NULL;
183
184	if (wps_build_version(msg) ||
185	    wps_build_msg_type(msg, WPS_M3) ||
186	    wps_build_registrar_nonce(wps, msg) ||
187	    wps_build_e_hash(wps, msg) ||
188	    wps_build_wfa_ext(msg, 0, NULL, 0) ||
189	    wps_build_authenticator(wps, msg)) {
190		wpabuf_free(msg);
191		return NULL;
192	}
193
194	wps->state = RECV_M4;
195	return msg;
196}
197
198
199static struct wpabuf * wps_build_m5(struct wps_data *wps)
200{
201	struct wpabuf *msg, *plain;
202
203	wpa_printf(MSG_DEBUG, "WPS: Building Message M5");
204
205	plain = wpabuf_alloc(200);
206	if (plain == NULL)
207		return NULL;
208
209	msg = wpabuf_alloc(1000);
210	if (msg == NULL) {
211		wpabuf_free(plain);
212		return NULL;
213	}
214
215	if (wps_build_version(msg) ||
216	    wps_build_msg_type(msg, WPS_M5) ||
217	    wps_build_registrar_nonce(wps, msg) ||
218	    wps_build_e_snonce1(wps, plain) ||
219	    wps_build_key_wrap_auth(wps, plain) ||
220	    wps_build_encr_settings(wps, msg, plain) ||
221	    wps_build_wfa_ext(msg, 0, NULL, 0) ||
222	    wps_build_authenticator(wps, msg)) {
223		wpabuf_free(plain);
224		wpabuf_free(msg);
225		return NULL;
226	}
227	wpabuf_free(plain);
228
229	wps->state = RECV_M6;
230	return msg;
231}
232
233
234static int wps_build_cred_ssid(struct wps_data *wps, struct wpabuf *msg)
235{
236	wpa_printf(MSG_DEBUG, "WPS:  * SSID");
237	wpabuf_put_be16(msg, ATTR_SSID);
238	wpabuf_put_be16(msg, wps->wps->ssid_len);
239	wpabuf_put_data(msg, wps->wps->ssid, wps->wps->ssid_len);
240	return 0;
241}
242
243
244static int wps_build_cred_auth_type(struct wps_data *wps, struct wpabuf *msg)
245{
246	u16 auth_type = wps->wps->auth_types;
247
248	/* Select the best authentication type */
249	if (auth_type & WPS_AUTH_WPA2PSK)
250		auth_type = WPS_AUTH_WPA2PSK;
251	else if (auth_type & WPS_AUTH_WPAPSK)
252		auth_type = WPS_AUTH_WPAPSK;
253	else if (auth_type & WPS_AUTH_OPEN)
254		auth_type = WPS_AUTH_OPEN;
255	else if (auth_type & WPS_AUTH_SHARED)
256		auth_type = WPS_AUTH_SHARED;
257
258	wpa_printf(MSG_DEBUG, "WPS:  * Authentication Type (0x%x)", auth_type);
259	wpabuf_put_be16(msg, ATTR_AUTH_TYPE);
260	wpabuf_put_be16(msg, 2);
261	wpabuf_put_be16(msg, auth_type);
262	return 0;
263}
264
265
266static int wps_build_cred_encr_type(struct wps_data *wps, struct wpabuf *msg)
267{
268	u16 encr_type = wps->wps->encr_types;
269
270	/* Select the best encryption type */
271	if (wps->wps->auth_types & (WPS_AUTH_WPA2PSK | WPS_AUTH_WPAPSK)) {
272		if (encr_type & WPS_ENCR_AES)
273			encr_type = WPS_ENCR_AES;
274		else if (encr_type & WPS_ENCR_TKIP)
275			encr_type = WPS_ENCR_TKIP;
276	} else {
277		if (encr_type & WPS_ENCR_WEP)
278			encr_type = WPS_ENCR_WEP;
279		else if (encr_type & WPS_ENCR_NONE)
280			encr_type = WPS_ENCR_NONE;
281	}
282
283	wpa_printf(MSG_DEBUG, "WPS:  * Encryption Type (0x%x)", encr_type);
284	wpabuf_put_be16(msg, ATTR_ENCR_TYPE);
285	wpabuf_put_be16(msg, 2);
286	wpabuf_put_be16(msg, encr_type);
287	return 0;
288}
289
290
291static int wps_build_cred_network_key(struct wps_data *wps, struct wpabuf *msg)
292{
293	wpa_printf(MSG_DEBUG, "WPS:  * Network Key");
294	wpabuf_put_be16(msg, ATTR_NETWORK_KEY);
295	wpabuf_put_be16(msg, wps->wps->network_key_len);
296	wpabuf_put_data(msg, wps->wps->network_key, wps->wps->network_key_len);
297	return 0;
298}
299
300
301static int wps_build_cred_mac_addr(struct wps_data *wps, struct wpabuf *msg)
302{
303	wpa_printf(MSG_DEBUG, "WPS:  * MAC Address (AP BSSID)");
304	wpabuf_put_be16(msg, ATTR_MAC_ADDR);
305	wpabuf_put_be16(msg, ETH_ALEN);
306	wpabuf_put_data(msg, wps->wps->dev.mac_addr, ETH_ALEN);
307	return 0;
308}
309
310
311static int wps_build_ap_settings(struct wps_data *wps, struct wpabuf *plain)
312{
313	if (wps->wps->ap_settings) {
314		wpa_printf(MSG_DEBUG, "WPS:  * AP Settings (pre-configured)");
315		wpabuf_put_data(plain, wps->wps->ap_settings,
316				wps->wps->ap_settings_len);
317		return 0;
318	}
319
320	return wps_build_cred_ssid(wps, plain) ||
321		wps_build_cred_mac_addr(wps, plain) ||
322		wps_build_cred_auth_type(wps, plain) ||
323		wps_build_cred_encr_type(wps, plain) ||
324		wps_build_cred_network_key(wps, plain);
325}
326
327
328static struct wpabuf * wps_build_m7(struct wps_data *wps)
329{
330	struct wpabuf *msg, *plain;
331
332	wpa_printf(MSG_DEBUG, "WPS: Building Message M7");
333
334	plain = wpabuf_alloc(500 + wps->wps->ap_settings_len);
335	if (plain == NULL)
336		return NULL;
337
338	msg = wpabuf_alloc(1000 + wps->wps->ap_settings_len);
339	if (msg == NULL) {
340		wpabuf_free(plain);
341		return NULL;
342	}
343
344	if (wps_build_version(msg) ||
345	    wps_build_msg_type(msg, WPS_M7) ||
346	    wps_build_registrar_nonce(wps, msg) ||
347	    wps_build_e_snonce2(wps, plain) ||
348	    (wps->wps->ap && wps_build_ap_settings(wps, plain)) ||
349	    wps_build_key_wrap_auth(wps, plain) ||
350	    wps_build_encr_settings(wps, msg, plain) ||
351	    wps_build_wfa_ext(msg, 0, NULL, 0) ||
352	    wps_build_authenticator(wps, msg)) {
353		wpabuf_free(plain);
354		wpabuf_free(msg);
355		return NULL;
356	}
357	wpabuf_free(plain);
358
359	if (wps->wps->ap && wps->wps->registrar) {
360		/*
361		 * If the Registrar is only learning our current configuration,
362		 * it may not continue protocol run to successful completion.
363		 * Store information here to make sure it remains available.
364		 */
365		wps_device_store(wps->wps->registrar, &wps->peer_dev,
366				 wps->uuid_r);
367	}
368
369	wps->state = RECV_M8;
370	return msg;
371}
372
373
374static struct wpabuf * wps_build_wsc_done(struct wps_data *wps)
375{
376	struct wpabuf *msg;
377
378	wpa_printf(MSG_DEBUG, "WPS: Building Message WSC_Done");
379
380	msg = wpabuf_alloc(1000);
381	if (msg == NULL)
382		return NULL;
383
384	if (wps_build_version(msg) ||
385	    wps_build_msg_type(msg, WPS_WSC_DONE) ||
386	    wps_build_enrollee_nonce(wps, msg) ||
387	    wps_build_registrar_nonce(wps, msg) ||
388	    wps_build_wfa_ext(msg, 0, NULL, 0)) {
389		wpabuf_free(msg);
390		return NULL;
391	}
392
393	if (wps->wps->ap)
394		wps->state = RECV_ACK;
395	else {
396		wps_success_event(wps->wps, wps->peer_dev.mac_addr);
397		wps->state = WPS_FINISHED;
398	}
399	return msg;
400}
401
402
403struct wpabuf * wps_enrollee_get_msg(struct wps_data *wps,
404				     enum wsc_op_code *op_code)
405{
406	struct wpabuf *msg;
407
408	switch (wps->state) {
409	case SEND_M1:
410		msg = wps_build_m1(wps);
411		*op_code = WSC_MSG;
412		break;
413	case SEND_M3:
414		msg = wps_build_m3(wps);
415		*op_code = WSC_MSG;
416		break;
417	case SEND_M5:
418		msg = wps_build_m5(wps);
419		*op_code = WSC_MSG;
420		break;
421	case SEND_M7:
422		msg = wps_build_m7(wps);
423		*op_code = WSC_MSG;
424		break;
425	case RECEIVED_M2D:
426		if (wps->wps->ap) {
427			msg = wps_build_wsc_nack(wps);
428			*op_code = WSC_NACK;
429			break;
430		}
431		msg = wps_build_wsc_ack(wps);
432		*op_code = WSC_ACK;
433		if (msg) {
434			/* Another M2/M2D may be received */
435			wps->state = RECV_M2;
436		}
437		break;
438	case SEND_WSC_NACK:
439		msg = wps_build_wsc_nack(wps);
440		*op_code = WSC_NACK;
441		break;
442	case WPS_MSG_DONE:
443		msg = wps_build_wsc_done(wps);
444		*op_code = WSC_Done;
445		break;
446	default:
447		wpa_printf(MSG_DEBUG, "WPS: Unsupported state %d for building "
448			   "a message", wps->state);
449		msg = NULL;
450		break;
451	}
452
453	if (*op_code == WSC_MSG && msg) {
454		/* Save a copy of the last message for Authenticator derivation
455		 */
456		wpabuf_free(wps->last_msg);
457		wps->last_msg = wpabuf_dup(msg);
458	}
459
460	return msg;
461}
462
463
464static int wps_process_registrar_nonce(struct wps_data *wps, const u8 *r_nonce)
465{
466	if (r_nonce == NULL) {
467		wpa_printf(MSG_DEBUG, "WPS: No Registrar Nonce received");
468		return -1;
469	}
470
471	os_memcpy(wps->nonce_r, r_nonce, WPS_NONCE_LEN);
472	wpa_hexdump(MSG_DEBUG, "WPS: Registrar Nonce",
473		    wps->nonce_r, WPS_NONCE_LEN);
474
475	return 0;
476}
477
478
479static int wps_process_enrollee_nonce(struct wps_data *wps, const u8 *e_nonce)
480{
481	if (e_nonce == NULL) {
482		wpa_printf(MSG_DEBUG, "WPS: No Enrollee Nonce received");
483		return -1;
484	}
485
486	if (os_memcmp(wps->nonce_e, e_nonce, WPS_NONCE_LEN) != 0) {
487		wpa_printf(MSG_DEBUG, "WPS: Invalid Enrollee Nonce received");
488		return -1;
489	}
490
491	return 0;
492}
493
494
495static int wps_process_uuid_r(struct wps_data *wps, const u8 *uuid_r)
496{
497	if (uuid_r == NULL) {
498		wpa_printf(MSG_DEBUG, "WPS: No UUID-R received");
499		return -1;
500	}
501
502	os_memcpy(wps->uuid_r, uuid_r, WPS_UUID_LEN);
503	wpa_hexdump(MSG_DEBUG, "WPS: UUID-R", wps->uuid_r, WPS_UUID_LEN);
504
505	return 0;
506}
507
508
509static int wps_process_pubkey(struct wps_data *wps, const u8 *pk,
510			      size_t pk_len)
511{
512	if (pk == NULL || pk_len == 0) {
513		wpa_printf(MSG_DEBUG, "WPS: No Public Key received");
514		return -1;
515	}
516
517	if (wps->peer_pubkey_hash_set) {
518		u8 hash[WPS_HASH_LEN];
519		sha256_vector(1, &pk, &pk_len, hash);
520		if (os_memcmp(hash, wps->peer_pubkey_hash,
521			      WPS_OOB_PUBKEY_HASH_LEN) != 0) {
522			wpa_printf(MSG_ERROR, "WPS: Public Key hash mismatch");
523			wpa_hexdump(MSG_DEBUG, "WPS: Received public key",
524				    pk, pk_len);
525			wpa_hexdump(MSG_DEBUG, "WPS: Calculated public key "
526				    "hash", hash, WPS_OOB_PUBKEY_HASH_LEN);
527			wpa_hexdump(MSG_DEBUG, "WPS: Expected public key hash",
528				    wps->peer_pubkey_hash,
529				    WPS_OOB_PUBKEY_HASH_LEN);
530			wps->config_error = WPS_CFG_PUBLIC_KEY_HASH_MISMATCH;
531			return -1;
532		}
533	}
534
535	wpabuf_free(wps->dh_pubkey_r);
536	wps->dh_pubkey_r = wpabuf_alloc_copy(pk, pk_len);
537	if (wps->dh_pubkey_r == NULL)
538		return -1;
539
540	if (wps_derive_keys(wps) < 0)
541		return -1;
542
543	return 0;
544}
545
546
547static int wps_process_r_hash1(struct wps_data *wps, const u8 *r_hash1)
548{
549	if (r_hash1 == NULL) {
550		wpa_printf(MSG_DEBUG, "WPS: No R-Hash1 received");
551		return -1;
552	}
553
554	os_memcpy(wps->peer_hash1, r_hash1, WPS_HASH_LEN);
555	wpa_hexdump(MSG_DEBUG, "WPS: R-Hash1", wps->peer_hash1, WPS_HASH_LEN);
556
557	return 0;
558}
559
560
561static int wps_process_r_hash2(struct wps_data *wps, const u8 *r_hash2)
562{
563	if (r_hash2 == NULL) {
564		wpa_printf(MSG_DEBUG, "WPS: No R-Hash2 received");
565		return -1;
566	}
567
568	os_memcpy(wps->peer_hash2, r_hash2, WPS_HASH_LEN);
569	wpa_hexdump(MSG_DEBUG, "WPS: R-Hash2", wps->peer_hash2, WPS_HASH_LEN);
570
571	return 0;
572}
573
574
575static int wps_process_r_snonce1(struct wps_data *wps, const u8 *r_snonce1)
576{
577	u8 hash[SHA256_MAC_LEN];
578	const u8 *addr[4];
579	size_t len[4];
580
581	if (r_snonce1 == NULL) {
582		wpa_printf(MSG_DEBUG, "WPS: No R-SNonce1 received");
583		return -1;
584	}
585
586	wpa_hexdump_key(MSG_DEBUG, "WPS: R-SNonce1", r_snonce1,
587			WPS_SECRET_NONCE_LEN);
588
589	/* R-Hash1 = HMAC_AuthKey(R-S1 || PSK1 || PK_E || PK_R) */
590	addr[0] = r_snonce1;
591	len[0] = WPS_SECRET_NONCE_LEN;
592	addr[1] = wps->psk1;
593	len[1] = WPS_PSK_LEN;
594	addr[2] = wpabuf_head(wps->dh_pubkey_e);
595	len[2] = wpabuf_len(wps->dh_pubkey_e);
596	addr[3] = wpabuf_head(wps->dh_pubkey_r);
597	len[3] = wpabuf_len(wps->dh_pubkey_r);
598	hmac_sha256_vector(wps->authkey, WPS_AUTHKEY_LEN, 4, addr, len, hash);
599
600	if (os_memcmp(wps->peer_hash1, hash, WPS_HASH_LEN) != 0) {
601		wpa_printf(MSG_DEBUG, "WPS: R-Hash1 derived from R-S1 does "
602			   "not match with the pre-committed value");
603		wps->config_error = WPS_CFG_DEV_PASSWORD_AUTH_FAILURE;
604		wps_pwd_auth_fail_event(wps->wps, 1, 1, wps->peer_dev.mac_addr);
605		return -1;
606	}
607
608	wpa_printf(MSG_DEBUG, "WPS: Registrar proved knowledge of the first "
609		   "half of the device password");
610
611	return 0;
612}
613
614
615static int wps_process_r_snonce2(struct wps_data *wps, const u8 *r_snonce2)
616{
617	u8 hash[SHA256_MAC_LEN];
618	const u8 *addr[4];
619	size_t len[4];
620
621	if (r_snonce2 == NULL) {
622		wpa_printf(MSG_DEBUG, "WPS: No R-SNonce2 received");
623		return -1;
624	}
625
626	wpa_hexdump_key(MSG_DEBUG, "WPS: R-SNonce2", r_snonce2,
627			WPS_SECRET_NONCE_LEN);
628
629	/* R-Hash2 = HMAC_AuthKey(R-S2 || PSK2 || PK_E || PK_R) */
630	addr[0] = r_snonce2;
631	len[0] = WPS_SECRET_NONCE_LEN;
632	addr[1] = wps->psk2;
633	len[1] = WPS_PSK_LEN;
634	addr[2] = wpabuf_head(wps->dh_pubkey_e);
635	len[2] = wpabuf_len(wps->dh_pubkey_e);
636	addr[3] = wpabuf_head(wps->dh_pubkey_r);
637	len[3] = wpabuf_len(wps->dh_pubkey_r);
638	hmac_sha256_vector(wps->authkey, WPS_AUTHKEY_LEN, 4, addr, len, hash);
639
640	if (os_memcmp(wps->peer_hash2, hash, WPS_HASH_LEN) != 0) {
641		wpa_printf(MSG_DEBUG, "WPS: R-Hash2 derived from R-S2 does "
642			   "not match with the pre-committed value");
643		wps->config_error = WPS_CFG_DEV_PASSWORD_AUTH_FAILURE;
644		wps_pwd_auth_fail_event(wps->wps, 1, 2, wps->peer_dev.mac_addr);
645		return -1;
646	}
647
648	wpa_printf(MSG_DEBUG, "WPS: Registrar proved knowledge of the second "
649		   "half of the device password");
650
651	return 0;
652}
653
654
655static int wps_process_cred_e(struct wps_data *wps, const u8 *cred,
656			      size_t cred_len, int wps2)
657{
658	struct wps_parse_attr attr;
659	struct wpabuf msg;
660	int ret = 0;
661
662	wpa_printf(MSG_DEBUG, "WPS: Received Credential");
663	os_memset(&wps->cred, 0, sizeof(wps->cred));
664	wpabuf_set(&msg, cred, cred_len);
665	if (wps_parse_msg(&msg, &attr) < 0 ||
666	    wps_process_cred(&attr, &wps->cred))
667		return -1;
668
669	if (os_memcmp(wps->cred.mac_addr, wps->wps->dev.mac_addr, ETH_ALEN) !=
670	    0) {
671		wpa_printf(MSG_DEBUG, "WPS: MAC Address in the Credential ("
672			   MACSTR ") does not match with own address (" MACSTR
673			   ")", MAC2STR(wps->cred.mac_addr),
674			   MAC2STR(wps->wps->dev.mac_addr));
675		/*
676		 * In theory, this could be consider fatal error, but there are
677		 * number of deployed implementations using other address here
678		 * due to unclarity in the specification. For interoperability
679		 * reasons, allow this to be processed since we do not really
680		 * use the MAC Address information for anything.
681		 */
682#ifdef CONFIG_WPS_STRICT
683		if (wps2) {
684			wpa_printf(MSG_INFO, "WPS: Do not accept incorrect "
685				   "MAC Address in AP Settings");
686			return -1;
687		}
688#endif /* CONFIG_WPS_STRICT */
689	}
690
691#ifdef CONFIG_WPS2
692	if (!(wps->cred.encr_type &
693	      (WPS_ENCR_NONE | WPS_ENCR_TKIP | WPS_ENCR_AES))) {
694		if (wps->cred.encr_type & WPS_ENCR_WEP) {
695			wpa_printf(MSG_INFO, "WPS: Reject Credential "
696				   "due to WEP configuration");
697			wps->error_indication = WPS_EI_SECURITY_WEP_PROHIBITED;
698			return -2;
699		}
700
701		wpa_printf(MSG_INFO, "WPS: Reject Credential due to "
702			   "invalid encr_type 0x%x", wps->cred.encr_type);
703		return -1;
704	}
705#endif /* CONFIG_WPS2 */
706
707	if (wps->wps->cred_cb) {
708		wps->cred.cred_attr = cred - 4;
709		wps->cred.cred_attr_len = cred_len + 4;
710		ret = wps->wps->cred_cb(wps->wps->cb_ctx, &wps->cred);
711		wps->cred.cred_attr = NULL;
712		wps->cred.cred_attr_len = 0;
713	}
714
715	return ret;
716}
717
718
719static int wps_process_creds(struct wps_data *wps, const u8 *cred[],
720			     size_t cred_len[], size_t num_cred, int wps2)
721{
722	size_t i;
723	int ok = 0;
724
725	if (wps->wps->ap)
726		return 0;
727
728	if (num_cred == 0) {
729		wpa_printf(MSG_DEBUG, "WPS: No Credential attributes "
730			   "received");
731		return -1;
732	}
733
734	for (i = 0; i < num_cred; i++) {
735		int res;
736		res = wps_process_cred_e(wps, cred[i], cred_len[i], wps2);
737		if (res == 0)
738			ok++;
739		else if (res == -2)
740			wpa_printf(MSG_DEBUG, "WPS: WEP credential skipped");
741		else
742			return -1;
743	}
744
745	if (ok == 0) {
746		wpa_printf(MSG_DEBUG, "WPS: No valid Credential attribute "
747			   "received");
748		return -1;
749	}
750
751	return 0;
752}
753
754
755static int wps_process_ap_settings_e(struct wps_data *wps,
756				     struct wps_parse_attr *attr,
757				     struct wpabuf *attrs, int wps2)
758{
759	struct wps_credential cred;
760
761	if (!wps->wps->ap)
762		return 0;
763
764	if (wps_process_ap_settings(attr, &cred) < 0)
765		return -1;
766
767	wpa_printf(MSG_INFO, "WPS: Received new AP configuration from "
768		   "Registrar");
769
770	if (os_memcmp(cred.mac_addr, wps->wps->dev.mac_addr, ETH_ALEN) !=
771	    0) {
772		wpa_printf(MSG_DEBUG, "WPS: MAC Address in the AP Settings ("
773			   MACSTR ") does not match with own address (" MACSTR
774			   ")", MAC2STR(cred.mac_addr),
775			   MAC2STR(wps->wps->dev.mac_addr));
776		/*
777		 * In theory, this could be consider fatal error, but there are
778		 * number of deployed implementations using other address here
779		 * due to unclarity in the specification. For interoperability
780		 * reasons, allow this to be processed since we do not really
781		 * use the MAC Address information for anything.
782		 */
783#ifdef CONFIG_WPS_STRICT
784		if (wps2) {
785			wpa_printf(MSG_INFO, "WPS: Do not accept incorrect "
786				   "MAC Address in AP Settings");
787			return -1;
788		}
789#endif /* CONFIG_WPS_STRICT */
790	}
791
792#ifdef CONFIG_WPS2
793	if (!(cred.encr_type & (WPS_ENCR_NONE | WPS_ENCR_TKIP | WPS_ENCR_AES)))
794	{
795		if (cred.encr_type & WPS_ENCR_WEP) {
796			wpa_printf(MSG_INFO, "WPS: Reject new AP settings "
797				   "due to WEP configuration");
798			wps->error_indication = WPS_EI_SECURITY_WEP_PROHIBITED;
799			return -1;
800		}
801
802		wpa_printf(MSG_INFO, "WPS: Reject new AP settings due to "
803			   "invalid encr_type 0x%x", cred.encr_type);
804		return -1;
805	}
806#endif /* CONFIG_WPS2 */
807
808#ifdef CONFIG_WPS_STRICT
809	if (wps2) {
810		if ((cred.encr_type & (WPS_ENCR_TKIP | WPS_ENCR_AES)) ==
811		    WPS_ENCR_TKIP ||
812		    (cred.auth_type & (WPS_AUTH_WPAPSK | WPS_AUTH_WPA2PSK)) ==
813		    WPS_AUTH_WPAPSK) {
814			wpa_printf(MSG_INFO, "WPS-STRICT: Invalid WSC 2.0 "
815				   "AP Settings: WPA-Personal/TKIP only");
816			wps->error_indication =
817				WPS_EI_SECURITY_TKIP_ONLY_PROHIBITED;
818			return -1;
819		}
820	}
821#endif /* CONFIG_WPS_STRICT */
822
823#ifdef CONFIG_WPS2
824	if ((cred.encr_type & (WPS_ENCR_TKIP | WPS_ENCR_AES)) == WPS_ENCR_TKIP)
825	{
826		wpa_printf(MSG_DEBUG, "WPS: Upgrade encr_type TKIP -> "
827			   "TKIP+AES");
828		cred.encr_type |= WPS_ENCR_AES;
829	}
830
831	if ((cred.auth_type & (WPS_AUTH_WPAPSK | WPS_AUTH_WPA2PSK)) ==
832	    WPS_AUTH_WPAPSK) {
833		wpa_printf(MSG_DEBUG, "WPS: Upgrade auth_type WPAPSK -> "
834			   "WPAPSK+WPA2PSK");
835		cred.auth_type |= WPS_AUTH_WPA2PSK;
836	}
837#endif /* CONFIG_WPS2 */
838
839	if (wps->wps->cred_cb) {
840		cred.cred_attr = wpabuf_head(attrs);
841		cred.cred_attr_len = wpabuf_len(attrs);
842		wps->wps->cred_cb(wps->wps->cb_ctx, &cred);
843	}
844
845	return 0;
846}
847
848
849static int wps_process_dev_pw_id(struct wps_data *wps, const u8 *dev_pw_id)
850{
851	u16 id;
852
853	if (dev_pw_id == NULL) {
854		wpa_printf(MSG_DEBUG, "WPS: Device Password ID");
855		return -1;
856	}
857
858	id = WPA_GET_BE16(dev_pw_id);
859	if (wps->dev_pw_id == id) {
860		wpa_printf(MSG_DEBUG, "WPS: Device Password ID %u", id);
861		return 0;
862	}
863
864#ifdef CONFIG_P2P
865	if ((id == DEV_PW_DEFAULT &&
866	     wps->dev_pw_id == DEV_PW_REGISTRAR_SPECIFIED) ||
867	    (id == DEV_PW_REGISTRAR_SPECIFIED &&
868	     wps->dev_pw_id == DEV_PW_DEFAULT)) {
869		/*
870		 * Common P2P use cases indicate whether the PIN is from the
871		 * client or GO using Device Password Id in M1/M2 in a way that
872		 * does not look fully compliant with WSC specification. Anyway,
873		 * this is deployed and needs to be allowed, so ignore changes
874		 * between Registrar-Specified and Default PIN.
875		 */
876		wpa_printf(MSG_DEBUG, "WPS: Allow PIN Device Password ID "
877			   "change");
878		return 0;
879	}
880#endif /* CONFIG_P2P */
881
882	wpa_printf(MSG_DEBUG, "WPS: Registrar trying to change Device Password "
883		   "ID from %u to %u", wps->dev_pw_id, id);
884
885	if (wps->dev_pw_id == DEV_PW_PUSHBUTTON && id == DEV_PW_DEFAULT) {
886		wpa_printf(MSG_DEBUG,
887			   "WPS: Workaround - ignore PBC-to-PIN change");
888		return 0;
889	}
890
891	if (wps->alt_dev_password && wps->alt_dev_pw_id == id) {
892		wpa_printf(MSG_DEBUG, "WPS: Found a matching Device Password");
893		os_free(wps->dev_password);
894		wps->dev_pw_id = wps->alt_dev_pw_id;
895		wps->dev_password = wps->alt_dev_password;
896		wps->dev_password_len = wps->alt_dev_password_len;
897		wps->alt_dev_password = NULL;
898		wps->alt_dev_password_len = 0;
899		return 0;
900	}
901
902	return -1;
903}
904
905
906static enum wps_process_res wps_process_m2(struct wps_data *wps,
907					   const struct wpabuf *msg,
908					   struct wps_parse_attr *attr)
909{
910	wpa_printf(MSG_DEBUG, "WPS: Received M2");
911
912	if (wps->state != RECV_M2) {
913		wpa_printf(MSG_DEBUG, "WPS: Unexpected state (%d) for "
914			   "receiving M2", wps->state);
915		wps->state = SEND_WSC_NACK;
916		return WPS_CONTINUE;
917	}
918
919	if (wps_process_registrar_nonce(wps, attr->registrar_nonce) ||
920	    wps_process_enrollee_nonce(wps, attr->enrollee_nonce) ||
921	    wps_process_uuid_r(wps, attr->uuid_r) ||
922	    wps_process_dev_pw_id(wps, attr->dev_password_id)) {
923		wps->state = SEND_WSC_NACK;
924		return WPS_CONTINUE;
925	}
926
927	/*
928	 * Stop here on an AP as an Enrollee if AP Setup is locked unless the
929	 * special locked mode is used to allow protocol run up to M7 in order
930	 * to support external Registrars that only learn the current AP
931	 * configuration without changing it.
932	 */
933	if (wps->wps->ap &&
934	    ((wps->wps->ap_setup_locked && wps->wps->ap_setup_locked != 2) ||
935	     wps->dev_password == NULL)) {
936		wpa_printf(MSG_DEBUG, "WPS: AP Setup is locked - refuse "
937			   "registration of a new Registrar");
938		wps->config_error = WPS_CFG_SETUP_LOCKED;
939		wps->state = SEND_WSC_NACK;
940		return WPS_CONTINUE;
941	}
942
943	if (wps_process_pubkey(wps, attr->public_key, attr->public_key_len) ||
944	    wps_process_authenticator(wps, attr->authenticator, msg) ||
945	    wps_process_device_attrs(&wps->peer_dev, attr)) {
946		wps->state = SEND_WSC_NACK;
947		return WPS_CONTINUE;
948	}
949
950#ifdef CONFIG_WPS_NFC
951	if (wps->peer_pubkey_hash_set) {
952		struct wpabuf *decrypted;
953		struct wps_parse_attr eattr;
954
955		decrypted = wps_decrypt_encr_settings(wps, attr->encr_settings,
956						      attr->encr_settings_len);
957		if (decrypted == NULL) {
958			wpa_printf(MSG_DEBUG, "WPS: Failed to decrypt "
959				   "Encrypted Settings attribute");
960			wps->state = SEND_WSC_NACK;
961			return WPS_CONTINUE;
962		}
963
964		wpa_printf(MSG_DEBUG, "WPS: Processing decrypted Encrypted "
965			   "Settings attribute");
966		if (wps_parse_msg(decrypted, &eattr) < 0 ||
967		    wps_process_key_wrap_auth(wps, decrypted,
968					      eattr.key_wrap_auth) ||
969		    wps_process_creds(wps, eattr.cred, eattr.cred_len,
970				      eattr.num_cred, attr->version2 != NULL)) {
971			wpabuf_free(decrypted);
972			wps->state = SEND_WSC_NACK;
973			return WPS_CONTINUE;
974		}
975		wpabuf_free(decrypted);
976
977		wps->state = WPS_MSG_DONE;
978		return WPS_CONTINUE;
979	}
980#endif /* CONFIG_WPS_NFC */
981
982	wps->state = SEND_M3;
983	return WPS_CONTINUE;
984}
985
986
987static enum wps_process_res wps_process_m2d(struct wps_data *wps,
988					    struct wps_parse_attr *attr)
989{
990	wpa_printf(MSG_DEBUG, "WPS: Received M2D");
991
992	if (wps->state != RECV_M2) {
993		wpa_printf(MSG_DEBUG, "WPS: Unexpected state (%d) for "
994			   "receiving M2D", wps->state);
995		wps->state = SEND_WSC_NACK;
996		return WPS_CONTINUE;
997	}
998
999	wpa_hexdump_ascii(MSG_DEBUG, "WPS: Manufacturer",
1000			  attr->manufacturer, attr->manufacturer_len);
1001	wpa_hexdump_ascii(MSG_DEBUG, "WPS: Model Name",
1002			  attr->model_name, attr->model_name_len);
1003	wpa_hexdump_ascii(MSG_DEBUG, "WPS: Model Number",
1004			  attr->model_number, attr->model_number_len);
1005	wpa_hexdump_ascii(MSG_DEBUG, "WPS: Serial Number",
1006			  attr->serial_number, attr->serial_number_len);
1007	wpa_hexdump_ascii(MSG_DEBUG, "WPS: Device Name",
1008			  attr->dev_name, attr->dev_name_len);
1009
1010	if (wps->wps->event_cb) {
1011		union wps_event_data data;
1012		struct wps_event_m2d *m2d = &data.m2d;
1013		os_memset(&data, 0, sizeof(data));
1014		if (attr->config_methods)
1015			m2d->config_methods =
1016				WPA_GET_BE16(attr->config_methods);
1017		m2d->manufacturer = attr->manufacturer;
1018		m2d->manufacturer_len = attr->manufacturer_len;
1019		m2d->model_name = attr->model_name;
1020		m2d->model_name_len = attr->model_name_len;
1021		m2d->model_number = attr->model_number;
1022		m2d->model_number_len = attr->model_number_len;
1023		m2d->serial_number = attr->serial_number;
1024		m2d->serial_number_len = attr->serial_number_len;
1025		m2d->dev_name = attr->dev_name;
1026		m2d->dev_name_len = attr->dev_name_len;
1027		m2d->primary_dev_type = attr->primary_dev_type;
1028		if (attr->config_error)
1029			m2d->config_error =
1030				WPA_GET_BE16(attr->config_error);
1031		if (attr->dev_password_id)
1032			m2d->dev_password_id =
1033				WPA_GET_BE16(attr->dev_password_id);
1034		wps->wps->event_cb(wps->wps->cb_ctx, WPS_EV_M2D, &data);
1035	}
1036
1037	wps->state = RECEIVED_M2D;
1038	return WPS_CONTINUE;
1039}
1040
1041
1042static enum wps_process_res wps_process_m4(struct wps_data *wps,
1043					   const struct wpabuf *msg,
1044					   struct wps_parse_attr *attr)
1045{
1046	struct wpabuf *decrypted;
1047	struct wps_parse_attr eattr;
1048
1049	wpa_printf(MSG_DEBUG, "WPS: Received M4");
1050
1051	if (wps->state != RECV_M4) {
1052		wpa_printf(MSG_DEBUG, "WPS: Unexpected state (%d) for "
1053			   "receiving M4", wps->state);
1054		wps->state = SEND_WSC_NACK;
1055		return WPS_CONTINUE;
1056	}
1057
1058	if (wps_process_enrollee_nonce(wps, attr->enrollee_nonce) ||
1059	    wps_process_authenticator(wps, attr->authenticator, msg) ||
1060	    wps_process_r_hash1(wps, attr->r_hash1) ||
1061	    wps_process_r_hash2(wps, attr->r_hash2)) {
1062		wps->state = SEND_WSC_NACK;
1063		return WPS_CONTINUE;
1064	}
1065
1066	decrypted = wps_decrypt_encr_settings(wps, attr->encr_settings,
1067					      attr->encr_settings_len);
1068	if (decrypted == NULL) {
1069		wpa_printf(MSG_DEBUG, "WPS: Failed to decrypted Encrypted "
1070			   "Settings attribute");
1071		wps->state = SEND_WSC_NACK;
1072		return WPS_CONTINUE;
1073	}
1074
1075	if (wps_validate_m4_encr(decrypted, attr->version2 != NULL) < 0) {
1076		wpabuf_free(decrypted);
1077		wps->state = SEND_WSC_NACK;
1078		return WPS_CONTINUE;
1079	}
1080
1081	wpa_printf(MSG_DEBUG, "WPS: Processing decrypted Encrypted Settings "
1082		   "attribute");
1083	if (wps_parse_msg(decrypted, &eattr) < 0 ||
1084	    wps_process_key_wrap_auth(wps, decrypted, eattr.key_wrap_auth) ||
1085	    wps_process_r_snonce1(wps, eattr.r_snonce1)) {
1086		wpabuf_free(decrypted);
1087		wps->state = SEND_WSC_NACK;
1088		return WPS_CONTINUE;
1089	}
1090	wpabuf_free(decrypted);
1091
1092	wps->state = SEND_M5;
1093	return WPS_CONTINUE;
1094}
1095
1096
1097static enum wps_process_res wps_process_m6(struct wps_data *wps,
1098					   const struct wpabuf *msg,
1099					   struct wps_parse_attr *attr)
1100{
1101	struct wpabuf *decrypted;
1102	struct wps_parse_attr eattr;
1103
1104	wpa_printf(MSG_DEBUG, "WPS: Received M6");
1105
1106	if (wps->state != RECV_M6) {
1107		wpa_printf(MSG_DEBUG, "WPS: Unexpected state (%d) for "
1108			   "receiving M6", wps->state);
1109		wps->state = SEND_WSC_NACK;
1110		return WPS_CONTINUE;
1111	}
1112
1113	if (wps_process_enrollee_nonce(wps, attr->enrollee_nonce) ||
1114	    wps_process_authenticator(wps, attr->authenticator, msg)) {
1115		wps->state = SEND_WSC_NACK;
1116		return WPS_CONTINUE;
1117	}
1118
1119	decrypted = wps_decrypt_encr_settings(wps, attr->encr_settings,
1120					      attr->encr_settings_len);
1121	if (decrypted == NULL) {
1122		wpa_printf(MSG_DEBUG, "WPS: Failed to decrypted Encrypted "
1123			   "Settings attribute");
1124		wps->state = SEND_WSC_NACK;
1125		return WPS_CONTINUE;
1126	}
1127
1128	if (wps_validate_m6_encr(decrypted, attr->version2 != NULL) < 0) {
1129		wpabuf_free(decrypted);
1130		wps->state = SEND_WSC_NACK;
1131		return WPS_CONTINUE;
1132	}
1133
1134	wpa_printf(MSG_DEBUG, "WPS: Processing decrypted Encrypted Settings "
1135		   "attribute");
1136	if (wps_parse_msg(decrypted, &eattr) < 0 ||
1137	    wps_process_key_wrap_auth(wps, decrypted, eattr.key_wrap_auth) ||
1138	    wps_process_r_snonce2(wps, eattr.r_snonce2)) {
1139		wpabuf_free(decrypted);
1140		wps->state = SEND_WSC_NACK;
1141		return WPS_CONTINUE;
1142	}
1143	wpabuf_free(decrypted);
1144
1145	if (wps->wps->ap)
1146		wps->wps->event_cb(wps->wps->cb_ctx, WPS_EV_AP_PIN_SUCCESS,
1147				   NULL);
1148
1149	wps->state = SEND_M7;
1150	return WPS_CONTINUE;
1151}
1152
1153
1154static enum wps_process_res wps_process_m8(struct wps_data *wps,
1155					   const struct wpabuf *msg,
1156					   struct wps_parse_attr *attr)
1157{
1158	struct wpabuf *decrypted;
1159	struct wps_parse_attr eattr;
1160
1161	wpa_printf(MSG_DEBUG, "WPS: Received M8");
1162
1163	if (wps->state != RECV_M8) {
1164		wpa_printf(MSG_DEBUG, "WPS: Unexpected state (%d) for "
1165			   "receiving M8", wps->state);
1166		wps->state = SEND_WSC_NACK;
1167		return WPS_CONTINUE;
1168	}
1169
1170	if (wps_process_enrollee_nonce(wps, attr->enrollee_nonce) ||
1171	    wps_process_authenticator(wps, attr->authenticator, msg)) {
1172		wps->state = SEND_WSC_NACK;
1173		return WPS_CONTINUE;
1174	}
1175
1176	if (wps->wps->ap && wps->wps->ap_setup_locked) {
1177		/*
1178		 * Stop here if special ap_setup_locked == 2 mode allowed the
1179		 * protocol to continue beyond M2. This allows ER to learn the
1180		 * current AP settings without changing them.
1181		 */
1182		wpa_printf(MSG_DEBUG, "WPS: AP Setup is locked - refuse "
1183			   "registration of a new Registrar");
1184		wps->config_error = WPS_CFG_SETUP_LOCKED;
1185		wps->state = SEND_WSC_NACK;
1186		return WPS_CONTINUE;
1187	}
1188
1189	decrypted = wps_decrypt_encr_settings(wps, attr->encr_settings,
1190					      attr->encr_settings_len);
1191	if (decrypted == NULL) {
1192		wpa_printf(MSG_DEBUG, "WPS: Failed to decrypted Encrypted "
1193			   "Settings attribute");
1194		wps->state = SEND_WSC_NACK;
1195		return WPS_CONTINUE;
1196	}
1197
1198	if (wps_validate_m8_encr(decrypted, wps->wps->ap,
1199				 attr->version2 != NULL) < 0) {
1200		wpabuf_free(decrypted);
1201		wps->state = SEND_WSC_NACK;
1202		return WPS_CONTINUE;
1203	}
1204
1205	wpa_printf(MSG_DEBUG, "WPS: Processing decrypted Encrypted Settings "
1206		   "attribute");
1207	if (wps_parse_msg(decrypted, &eattr) < 0 ||
1208	    wps_process_key_wrap_auth(wps, decrypted, eattr.key_wrap_auth) ||
1209	    wps_process_creds(wps, eattr.cred, eattr.cred_len,
1210			      eattr.num_cred, attr->version2 != NULL) ||
1211	    wps_process_ap_settings_e(wps, &eattr, decrypted,
1212				      attr->version2 != NULL)) {
1213		wpabuf_free(decrypted);
1214		wps->state = SEND_WSC_NACK;
1215		return WPS_CONTINUE;
1216	}
1217	wpabuf_free(decrypted);
1218
1219	wps->state = WPS_MSG_DONE;
1220	return WPS_CONTINUE;
1221}
1222
1223
1224static enum wps_process_res wps_process_wsc_msg(struct wps_data *wps,
1225						const struct wpabuf *msg)
1226{
1227	struct wps_parse_attr attr;
1228	enum wps_process_res ret = WPS_CONTINUE;
1229
1230	wpa_printf(MSG_DEBUG, "WPS: Received WSC_MSG");
1231
1232	if (wps_parse_msg(msg, &attr) < 0)
1233		return WPS_FAILURE;
1234
1235	if (attr.enrollee_nonce == NULL ||
1236	    os_memcmp(wps->nonce_e, attr.enrollee_nonce, WPS_NONCE_LEN) != 0) {
1237		wpa_printf(MSG_DEBUG, "WPS: Mismatch in enrollee nonce");
1238		return WPS_FAILURE;
1239	}
1240
1241	if (attr.msg_type == NULL) {
1242		wpa_printf(MSG_DEBUG, "WPS: No Message Type attribute");
1243		wps->state = SEND_WSC_NACK;
1244		return WPS_CONTINUE;
1245	}
1246
1247	switch (*attr.msg_type) {
1248	case WPS_M2:
1249		if (wps_validate_m2(msg) < 0)
1250			return WPS_FAILURE;
1251		ret = wps_process_m2(wps, msg, &attr);
1252		break;
1253	case WPS_M2D:
1254		if (wps_validate_m2d(msg) < 0)
1255			return WPS_FAILURE;
1256		ret = wps_process_m2d(wps, &attr);
1257		break;
1258	case WPS_M4:
1259		if (wps_validate_m4(msg) < 0)
1260			return WPS_FAILURE;
1261		ret = wps_process_m4(wps, msg, &attr);
1262		if (ret == WPS_FAILURE || wps->state == SEND_WSC_NACK)
1263			wps_fail_event(wps->wps, WPS_M4, wps->config_error,
1264				       wps->error_indication,
1265				       wps->peer_dev.mac_addr);
1266		break;
1267	case WPS_M6:
1268		if (wps_validate_m6(msg) < 0)
1269			return WPS_FAILURE;
1270		ret = wps_process_m6(wps, msg, &attr);
1271		if (ret == WPS_FAILURE || wps->state == SEND_WSC_NACK)
1272			wps_fail_event(wps->wps, WPS_M6, wps->config_error,
1273				       wps->error_indication,
1274				       wps->peer_dev.mac_addr);
1275		break;
1276	case WPS_M8:
1277		if (wps_validate_m8(msg) < 0)
1278			return WPS_FAILURE;
1279		ret = wps_process_m8(wps, msg, &attr);
1280		if (ret == WPS_FAILURE || wps->state == SEND_WSC_NACK)
1281			wps_fail_event(wps->wps, WPS_M8, wps->config_error,
1282				       wps->error_indication,
1283				       wps->peer_dev.mac_addr);
1284		break;
1285	default:
1286		wpa_printf(MSG_DEBUG, "WPS: Unsupported Message Type %d",
1287			   *attr.msg_type);
1288		return WPS_FAILURE;
1289	}
1290
1291	/*
1292	 * Save a copy of the last message for Authenticator derivation if we
1293	 * are continuing. However, skip M2D since it is not authenticated and
1294	 * neither is the ACK/NACK response frame. This allows the possibly
1295	 * following M2 to be processed correctly by using the previously sent
1296	 * M1 in Authenticator derivation.
1297	 */
1298	if (ret == WPS_CONTINUE && *attr.msg_type != WPS_M2D) {
1299		/* Save a copy of the last message for Authenticator derivation
1300		 */
1301		wpabuf_free(wps->last_msg);
1302		wps->last_msg = wpabuf_dup(msg);
1303	}
1304
1305	return ret;
1306}
1307
1308
1309static enum wps_process_res wps_process_wsc_ack(struct wps_data *wps,
1310						const struct wpabuf *msg)
1311{
1312	struct wps_parse_attr attr;
1313
1314	wpa_printf(MSG_DEBUG, "WPS: Received WSC_ACK");
1315
1316	if (wps_parse_msg(msg, &attr) < 0)
1317		return WPS_FAILURE;
1318
1319	if (attr.msg_type == NULL) {
1320		wpa_printf(MSG_DEBUG, "WPS: No Message Type attribute");
1321		return WPS_FAILURE;
1322	}
1323
1324	if (*attr.msg_type != WPS_WSC_ACK) {
1325		wpa_printf(MSG_DEBUG, "WPS: Invalid Message Type %d",
1326			   *attr.msg_type);
1327		return WPS_FAILURE;
1328	}
1329
1330	if (attr.registrar_nonce == NULL ||
1331	    os_memcmp(wps->nonce_r, attr.registrar_nonce, WPS_NONCE_LEN) != 0)
1332	{
1333		wpa_printf(MSG_DEBUG, "WPS: Mismatch in registrar nonce");
1334		return WPS_FAILURE;
1335	}
1336
1337	if (attr.enrollee_nonce == NULL ||
1338	    os_memcmp(wps->nonce_e, attr.enrollee_nonce, WPS_NONCE_LEN) != 0) {
1339		wpa_printf(MSG_DEBUG, "WPS: Mismatch in enrollee nonce");
1340		return WPS_FAILURE;
1341	}
1342
1343	if (wps->state == RECV_ACK && wps->wps->ap) {
1344		wpa_printf(MSG_DEBUG, "WPS: External Registrar registration "
1345			   "completed successfully");
1346		wps_success_event(wps->wps, wps->peer_dev.mac_addr);
1347		wps->state = WPS_FINISHED;
1348		return WPS_DONE;
1349	}
1350
1351	return WPS_FAILURE;
1352}
1353
1354
1355static enum wps_process_res wps_process_wsc_nack(struct wps_data *wps,
1356						 const struct wpabuf *msg)
1357{
1358	struct wps_parse_attr attr;
1359	u16 config_error;
1360
1361	wpa_printf(MSG_DEBUG, "WPS: Received WSC_NACK");
1362
1363	if (wps_parse_msg(msg, &attr) < 0)
1364		return WPS_FAILURE;
1365
1366	if (attr.msg_type == NULL) {
1367		wpa_printf(MSG_DEBUG, "WPS: No Message Type attribute");
1368		return WPS_FAILURE;
1369	}
1370
1371	if (*attr.msg_type != WPS_WSC_NACK) {
1372		wpa_printf(MSG_DEBUG, "WPS: Invalid Message Type %d",
1373			   *attr.msg_type);
1374		return WPS_FAILURE;
1375	}
1376
1377	if (attr.registrar_nonce == NULL ||
1378	    os_memcmp(wps->nonce_r, attr.registrar_nonce, WPS_NONCE_LEN) != 0)
1379	{
1380		wpa_printf(MSG_DEBUG, "WPS: Mismatch in registrar nonce");
1381		wpa_hexdump(MSG_DEBUG, "WPS: Received Registrar Nonce",
1382			    attr.registrar_nonce, WPS_NONCE_LEN);
1383		wpa_hexdump(MSG_DEBUG, "WPS: Expected Registrar Nonce",
1384			    wps->nonce_r, WPS_NONCE_LEN);
1385		return WPS_FAILURE;
1386	}
1387
1388	if (attr.enrollee_nonce == NULL ||
1389	    os_memcmp(wps->nonce_e, attr.enrollee_nonce, WPS_NONCE_LEN) != 0) {
1390		wpa_printf(MSG_DEBUG, "WPS: Mismatch in enrollee nonce");
1391		wpa_hexdump(MSG_DEBUG, "WPS: Received Enrollee Nonce",
1392			    attr.enrollee_nonce, WPS_NONCE_LEN);
1393		wpa_hexdump(MSG_DEBUG, "WPS: Expected Enrollee Nonce",
1394			    wps->nonce_e, WPS_NONCE_LEN);
1395		return WPS_FAILURE;
1396	}
1397
1398	if (attr.config_error == NULL) {
1399		wpa_printf(MSG_DEBUG, "WPS: No Configuration Error attribute "
1400			   "in WSC_NACK");
1401		return WPS_FAILURE;
1402	}
1403
1404	config_error = WPA_GET_BE16(attr.config_error);
1405	wpa_printf(MSG_DEBUG, "WPS: Registrar terminated negotiation with "
1406		   "Configuration Error %d", config_error);
1407
1408	switch (wps->state) {
1409	case RECV_M4:
1410		wps_fail_event(wps->wps, WPS_M3, config_error,
1411			       wps->error_indication, wps->peer_dev.mac_addr);
1412		break;
1413	case RECV_M6:
1414		wps_fail_event(wps->wps, WPS_M5, config_error,
1415			       wps->error_indication, wps->peer_dev.mac_addr);
1416		break;
1417	case RECV_M8:
1418		wps_fail_event(wps->wps, WPS_M7, config_error,
1419			       wps->error_indication, wps->peer_dev.mac_addr);
1420		break;
1421	default:
1422		break;
1423	}
1424
1425	/* Followed by NACK if Enrollee is Supplicant or EAP-Failure if
1426	 * Enrollee is Authenticator */
1427	wps->state = SEND_WSC_NACK;
1428
1429	return WPS_FAILURE;
1430}
1431
1432
1433enum wps_process_res wps_enrollee_process_msg(struct wps_data *wps,
1434					      enum wsc_op_code op_code,
1435					      const struct wpabuf *msg)
1436{
1437
1438	wpa_printf(MSG_DEBUG, "WPS: Processing received message (len=%lu "
1439		   "op_code=%d)",
1440		   (unsigned long) wpabuf_len(msg), op_code);
1441
1442	if (op_code == WSC_UPnP) {
1443		/* Determine the OpCode based on message type attribute */
1444		struct wps_parse_attr attr;
1445		if (wps_parse_msg(msg, &attr) == 0 && attr.msg_type) {
1446			if (*attr.msg_type == WPS_WSC_ACK)
1447				op_code = WSC_ACK;
1448			else if (*attr.msg_type == WPS_WSC_NACK)
1449				op_code = WSC_NACK;
1450		}
1451	}
1452
1453	switch (op_code) {
1454	case WSC_MSG:
1455	case WSC_UPnP:
1456		return wps_process_wsc_msg(wps, msg);
1457	case WSC_ACK:
1458		if (wps_validate_wsc_ack(msg) < 0)
1459			return WPS_FAILURE;
1460		return wps_process_wsc_ack(wps, msg);
1461	case WSC_NACK:
1462		if (wps_validate_wsc_nack(msg) < 0)
1463			return WPS_FAILURE;
1464		return wps_process_wsc_nack(wps, msg);
1465	default:
1466		wpa_printf(MSG_DEBUG, "WPS: Unsupported op_code %d", op_code);
1467		return WPS_FAILURE;
1468	}
1469}
1470