xref: /freebsd/contrib/wpa/src/wps/wps_enrollee.c (revision 148a8da8)
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 
19 static 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 
35 static 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 
83 static 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 
93 static 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 
104 static 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 		config_methods &= ~(WPS_CONFIG_VIRT_PUSHBUTTON |
134 				    WPS_CONFIG_PHY_PUSHBUTTON);
135 	}
136 
137 	if (wps_build_version(msg) ||
138 	    wps_build_msg_type(msg, WPS_M1) ||
139 	    wps_build_uuid_e(msg, wps->uuid_e) ||
140 	    wps_build_mac_addr(msg, wps->mac_addr_e) ||
141 	    wps_build_enrollee_nonce(wps, msg) ||
142 	    wps_build_public_key(wps, msg) ||
143 	    wps_build_auth_type_flags(wps, msg) ||
144 	    wps_build_encr_type_flags(wps, msg) ||
145 	    wps_build_conn_type_flags(wps, msg) ||
146 	    wps_build_config_methods(msg, config_methods) ||
147 	    wps_build_wps_state(wps, msg) ||
148 	    wps_build_device_attrs(&wps->wps->dev, msg) ||
149 	    wps_build_rf_bands(&wps->wps->dev, msg,
150 			       wps->wps->rf_band_cb(wps->wps->cb_ctx)) ||
151 	    wps_build_assoc_state(wps, msg) ||
152 	    wps_build_dev_password_id(msg, wps->dev_pw_id) ||
153 	    wps_build_config_error(msg, WPS_CFG_NO_ERROR) ||
154 	    wps_build_os_version(&wps->wps->dev, msg) ||
155 	    wps_build_wfa_ext(msg, 0, NULL, 0) ||
156 	    wps_build_vendor_ext_m1(&wps->wps->dev, msg)) {
157 		wpabuf_free(msg);
158 		return NULL;
159 	}
160 
161 	wps->state = RECV_M2;
162 	return msg;
163 }
164 
165 
166 static struct wpabuf * wps_build_m3(struct wps_data *wps)
167 {
168 	struct wpabuf *msg;
169 
170 	wpa_printf(MSG_DEBUG, "WPS: Building Message M3");
171 
172 	if (wps->dev_password == NULL) {
173 		wpa_printf(MSG_DEBUG, "WPS: No Device Password available");
174 		return NULL;
175 	}
176 	if (wps_derive_psk(wps, wps->dev_password, wps->dev_password_len) < 0)
177 		return NULL;
178 
179 	if (wps->wps->ap && random_pool_ready() != 1) {
180 		wpa_printf(MSG_INFO,
181 			   "WPS: Not enough entropy in random pool to proceed - do not allow AP PIN to be used");
182 		return NULL;
183 	}
184 
185 	msg = wpabuf_alloc(1000);
186 	if (msg == NULL)
187 		return NULL;
188 
189 	if (wps_build_version(msg) ||
190 	    wps_build_msg_type(msg, WPS_M3) ||
191 	    wps_build_registrar_nonce(wps, msg) ||
192 	    wps_build_e_hash(wps, msg) ||
193 	    wps_build_wfa_ext(msg, 0, NULL, 0) ||
194 	    wps_build_authenticator(wps, msg)) {
195 		wpabuf_free(msg);
196 		return NULL;
197 	}
198 
199 	wps->state = RECV_M4;
200 	return msg;
201 }
202 
203 
204 static struct wpabuf * wps_build_m5(struct wps_data *wps)
205 {
206 	struct wpabuf *msg, *plain;
207 
208 	wpa_printf(MSG_DEBUG, "WPS: Building Message M5");
209 
210 	plain = wpabuf_alloc(200);
211 	if (plain == NULL)
212 		return NULL;
213 
214 	msg = wpabuf_alloc(1000);
215 	if (msg == NULL) {
216 		wpabuf_free(plain);
217 		return NULL;
218 	}
219 
220 	if (wps_build_version(msg) ||
221 	    wps_build_msg_type(msg, WPS_M5) ||
222 	    wps_build_registrar_nonce(wps, msg) ||
223 	    wps_build_e_snonce1(wps, plain) ||
224 	    wps_build_key_wrap_auth(wps, plain) ||
225 	    wps_build_encr_settings(wps, msg, plain) ||
226 	    wps_build_wfa_ext(msg, 0, NULL, 0) ||
227 	    wps_build_authenticator(wps, msg)) {
228 		wpabuf_clear_free(plain);
229 		wpabuf_free(msg);
230 		return NULL;
231 	}
232 	wpabuf_clear_free(plain);
233 
234 	wps->state = RECV_M6;
235 	return msg;
236 }
237 
238 
239 static int wps_build_cred_ssid(struct wps_data *wps, struct wpabuf *msg)
240 {
241 	wpa_printf(MSG_DEBUG, "WPS:  * SSID");
242 	wpabuf_put_be16(msg, ATTR_SSID);
243 	wpabuf_put_be16(msg, wps->wps->ssid_len);
244 	wpabuf_put_data(msg, wps->wps->ssid, wps->wps->ssid_len);
245 	return 0;
246 }
247 
248 
249 static int wps_build_cred_auth_type(struct wps_data *wps, struct wpabuf *msg)
250 {
251 	u16 auth_type = wps->wps->ap_auth_type;
252 
253 	/*
254 	 * Work around issues with Windows 7 WPS implementation not liking
255 	 * multiple Authentication Type bits in M7 AP Settings attribute by
256 	 * showing only the most secure option from current configuration.
257 	 */
258 	if (auth_type & WPS_AUTH_WPA2PSK)
259 		auth_type = WPS_AUTH_WPA2PSK;
260 	else if (auth_type & WPS_AUTH_WPAPSK)
261 		auth_type = WPS_AUTH_WPAPSK;
262 	else if (auth_type & WPS_AUTH_OPEN)
263 		auth_type = WPS_AUTH_OPEN;
264 
265 	wpa_printf(MSG_DEBUG, "WPS:  * Authentication Type (0x%x)", auth_type);
266 	wpabuf_put_be16(msg, ATTR_AUTH_TYPE);
267 	wpabuf_put_be16(msg, 2);
268 	wpabuf_put_be16(msg, auth_type);
269 	return 0;
270 }
271 
272 
273 static int wps_build_cred_encr_type(struct wps_data *wps, struct wpabuf *msg)
274 {
275 	u16 encr_type = wps->wps->ap_encr_type;
276 
277 	/*
278 	 * Work around issues with Windows 7 WPS implementation not liking
279 	 * multiple Encryption Type bits in M7 AP Settings attribute by
280 	 * showing only the most secure option from current configuration.
281 	 */
282 	if (wps->wps->ap_auth_type & (WPS_AUTH_WPA2PSK | WPS_AUTH_WPAPSK)) {
283 		if (encr_type & WPS_ENCR_AES)
284 			encr_type = WPS_ENCR_AES;
285 		else if (encr_type & WPS_ENCR_TKIP)
286 			encr_type = WPS_ENCR_TKIP;
287 	}
288 
289 	wpa_printf(MSG_DEBUG, "WPS:  * Encryption Type (0x%x)", encr_type);
290 	wpabuf_put_be16(msg, ATTR_ENCR_TYPE);
291 	wpabuf_put_be16(msg, 2);
292 	wpabuf_put_be16(msg, encr_type);
293 	return 0;
294 }
295 
296 
297 static int wps_build_cred_network_key(struct wps_data *wps, struct wpabuf *msg)
298 {
299 	if ((wps->wps->ap_auth_type & (WPS_AUTH_WPAPSK | WPS_AUTH_WPA2PSK)) &&
300 	    wps->wps->network_key_len == 0) {
301 		char hex[65];
302 		u8 psk[32];
303 		/* Generate a random per-device PSK */
304 		if (random_pool_ready() != 1 ||
305 		    random_get_bytes(psk, sizeof(psk)) < 0) {
306 			wpa_printf(MSG_INFO,
307 				   "WPS: Could not generate random PSK");
308 			return -1;
309 		}
310 		wpa_hexdump_key(MSG_DEBUG, "WPS: Generated per-device PSK",
311 				psk, sizeof(psk));
312 		wpa_printf(MSG_DEBUG, "WPS:  * Network Key (len=%u)",
313 			   (unsigned int) wps->new_psk_len * 2);
314 		wpa_snprintf_hex(hex, sizeof(hex), psk, sizeof(psk));
315 		wpabuf_put_be16(msg, ATTR_NETWORK_KEY);
316 		wpabuf_put_be16(msg, sizeof(psk) * 2);
317 		wpabuf_put_data(msg, hex, sizeof(psk) * 2);
318 		if (wps->wps->registrar) {
319 			wps_cb_new_psk(wps->wps->registrar,
320 				       wps->peer_dev.mac_addr,
321 				       wps->p2p_dev_addr, psk, sizeof(psk));
322 		}
323 		return 0;
324 	}
325 
326 	wpa_printf(MSG_DEBUG, "WPS:  * Network Key (len=%u)",
327 		   (unsigned int) wps->wps->network_key_len);
328 	wpabuf_put_be16(msg, ATTR_NETWORK_KEY);
329 	wpabuf_put_be16(msg, wps->wps->network_key_len);
330 	wpabuf_put_data(msg, wps->wps->network_key, wps->wps->network_key_len);
331 	return 0;
332 }
333 
334 
335 static int wps_build_cred_mac_addr(struct wps_data *wps, struct wpabuf *msg)
336 {
337 	wpa_printf(MSG_DEBUG, "WPS:  * MAC Address (AP BSSID)");
338 	wpabuf_put_be16(msg, ATTR_MAC_ADDR);
339 	wpabuf_put_be16(msg, ETH_ALEN);
340 	wpabuf_put_data(msg, wps->wps->dev.mac_addr, ETH_ALEN);
341 	return 0;
342 }
343 
344 
345 static int wps_build_ap_settings(struct wps_data *wps, struct wpabuf *plain)
346 {
347 	const u8 *start, *end;
348 	int ret;
349 
350 	if (wps->wps->ap_settings) {
351 		wpa_printf(MSG_DEBUG, "WPS:  * AP Settings (pre-configured)");
352 		wpabuf_put_data(plain, wps->wps->ap_settings,
353 				wps->wps->ap_settings_len);
354 		return 0;
355 	}
356 
357 	wpa_printf(MSG_DEBUG, "WPS:  * AP Settings based on current configuration");
358 	start = wpabuf_put(plain, 0);
359 	ret = wps_build_cred_ssid(wps, plain) ||
360 		wps_build_cred_mac_addr(wps, plain) ||
361 		wps_build_cred_auth_type(wps, plain) ||
362 		wps_build_cred_encr_type(wps, plain) ||
363 		wps_build_cred_network_key(wps, plain);
364 	end = wpabuf_put(plain, 0);
365 
366 	wpa_hexdump_key(MSG_DEBUG, "WPS: Plaintext AP Settings",
367 			start, end - start);
368 
369 	return ret;
370 }
371 
372 
373 static struct wpabuf * wps_build_m7(struct wps_data *wps)
374 {
375 	struct wpabuf *msg, *plain;
376 
377 	wpa_printf(MSG_DEBUG, "WPS: Building Message M7");
378 
379 	plain = wpabuf_alloc(500 + wps->wps->ap_settings_len);
380 	if (plain == NULL)
381 		return NULL;
382 
383 	msg = wpabuf_alloc(1000 + wps->wps->ap_settings_len);
384 	if (msg == NULL) {
385 		wpabuf_free(plain);
386 		return NULL;
387 	}
388 
389 	if (wps_build_version(msg) ||
390 	    wps_build_msg_type(msg, WPS_M7) ||
391 	    wps_build_registrar_nonce(wps, msg) ||
392 	    wps_build_e_snonce2(wps, plain) ||
393 	    (wps->wps->ap && wps_build_ap_settings(wps, plain)) ||
394 	    wps_build_key_wrap_auth(wps, plain) ||
395 	    wps_build_encr_settings(wps, msg, plain) ||
396 	    wps_build_wfa_ext(msg, 0, NULL, 0) ||
397 	    wps_build_authenticator(wps, msg)) {
398 		wpabuf_clear_free(plain);
399 		wpabuf_free(msg);
400 		return NULL;
401 	}
402 	wpabuf_clear_free(plain);
403 
404 	if (wps->wps->ap && wps->wps->registrar) {
405 		/*
406 		 * If the Registrar is only learning our current configuration,
407 		 * it may not continue protocol run to successful completion.
408 		 * Store information here to make sure it remains available.
409 		 */
410 		wps_device_store(wps->wps->registrar, &wps->peer_dev,
411 				 wps->uuid_r);
412 	}
413 
414 	wps->state = RECV_M8;
415 	return msg;
416 }
417 
418 
419 static struct wpabuf * wps_build_wsc_done(struct wps_data *wps)
420 {
421 	struct wpabuf *msg;
422 
423 	wpa_printf(MSG_DEBUG, "WPS: Building Message WSC_Done");
424 
425 	msg = wpabuf_alloc(1000);
426 	if (msg == NULL)
427 		return NULL;
428 
429 	if (wps_build_version(msg) ||
430 	    wps_build_msg_type(msg, WPS_WSC_DONE) ||
431 	    wps_build_enrollee_nonce(wps, msg) ||
432 	    wps_build_registrar_nonce(wps, msg) ||
433 	    wps_build_wfa_ext(msg, 0, NULL, 0)) {
434 		wpabuf_free(msg);
435 		return NULL;
436 	}
437 
438 	if (wps->wps->ap)
439 		wps->state = RECV_ACK;
440 	else {
441 		wps_success_event(wps->wps, wps->peer_dev.mac_addr);
442 		wps->state = WPS_FINISHED;
443 	}
444 	return msg;
445 }
446 
447 
448 struct wpabuf * wps_enrollee_get_msg(struct wps_data *wps,
449 				     enum wsc_op_code *op_code)
450 {
451 	struct wpabuf *msg;
452 
453 	switch (wps->state) {
454 	case SEND_M1:
455 		msg = wps_build_m1(wps);
456 		*op_code = WSC_MSG;
457 		break;
458 	case SEND_M3:
459 		msg = wps_build_m3(wps);
460 		*op_code = WSC_MSG;
461 		break;
462 	case SEND_M5:
463 		msg = wps_build_m5(wps);
464 		*op_code = WSC_MSG;
465 		break;
466 	case SEND_M7:
467 		msg = wps_build_m7(wps);
468 		*op_code = WSC_MSG;
469 		break;
470 	case RECEIVED_M2D:
471 		if (wps->wps->ap) {
472 			msg = wps_build_wsc_nack(wps);
473 			*op_code = WSC_NACK;
474 			break;
475 		}
476 		msg = wps_build_wsc_ack(wps);
477 		*op_code = WSC_ACK;
478 		if (msg) {
479 			/* Another M2/M2D may be received */
480 			wps->state = RECV_M2;
481 		}
482 		break;
483 	case SEND_WSC_NACK:
484 		msg = wps_build_wsc_nack(wps);
485 		*op_code = WSC_NACK;
486 		break;
487 	case WPS_MSG_DONE:
488 		msg = wps_build_wsc_done(wps);
489 		*op_code = WSC_Done;
490 		break;
491 	default:
492 		wpa_printf(MSG_DEBUG, "WPS: Unsupported state %d for building "
493 			   "a message", wps->state);
494 		msg = NULL;
495 		break;
496 	}
497 
498 	if (*op_code == WSC_MSG && msg) {
499 		/* Save a copy of the last message for Authenticator derivation
500 		 */
501 		wpabuf_free(wps->last_msg);
502 		wps->last_msg = wpabuf_dup(msg);
503 	}
504 
505 	return msg;
506 }
507 
508 
509 static int wps_process_registrar_nonce(struct wps_data *wps, const u8 *r_nonce)
510 {
511 	if (r_nonce == NULL) {
512 		wpa_printf(MSG_DEBUG, "WPS: No Registrar Nonce received");
513 		return -1;
514 	}
515 
516 	os_memcpy(wps->nonce_r, r_nonce, WPS_NONCE_LEN);
517 	wpa_hexdump(MSG_DEBUG, "WPS: Registrar Nonce",
518 		    wps->nonce_r, WPS_NONCE_LEN);
519 
520 	return 0;
521 }
522 
523 
524 static int wps_process_enrollee_nonce(struct wps_data *wps, const u8 *e_nonce)
525 {
526 	if (e_nonce == NULL) {
527 		wpa_printf(MSG_DEBUG, "WPS: No Enrollee Nonce received");
528 		return -1;
529 	}
530 
531 	if (os_memcmp(wps->nonce_e, e_nonce, WPS_NONCE_LEN) != 0) {
532 		wpa_printf(MSG_DEBUG, "WPS: Invalid Enrollee Nonce received");
533 		return -1;
534 	}
535 
536 	return 0;
537 }
538 
539 
540 static int wps_process_uuid_r(struct wps_data *wps, const u8 *uuid_r)
541 {
542 	if (uuid_r == NULL) {
543 		wpa_printf(MSG_DEBUG, "WPS: No UUID-R received");
544 		return -1;
545 	}
546 
547 	os_memcpy(wps->uuid_r, uuid_r, WPS_UUID_LEN);
548 	wpa_hexdump(MSG_DEBUG, "WPS: UUID-R", wps->uuid_r, WPS_UUID_LEN);
549 
550 	return 0;
551 }
552 
553 
554 static int wps_process_pubkey(struct wps_data *wps, const u8 *pk,
555 			      size_t pk_len)
556 {
557 	if (pk == NULL || pk_len == 0) {
558 		wpa_printf(MSG_DEBUG, "WPS: No Public Key received");
559 		return -1;
560 	}
561 
562 	if (wps->peer_pubkey_hash_set) {
563 		u8 hash[WPS_HASH_LEN];
564 		sha256_vector(1, &pk, &pk_len, hash);
565 		if (os_memcmp_const(hash, wps->peer_pubkey_hash,
566 				    WPS_OOB_PUBKEY_HASH_LEN) != 0) {
567 			wpa_printf(MSG_ERROR, "WPS: Public Key hash mismatch");
568 			wpa_hexdump(MSG_DEBUG, "WPS: Received public key",
569 				    pk, pk_len);
570 			wpa_hexdump(MSG_DEBUG, "WPS: Calculated public key "
571 				    "hash", hash, WPS_OOB_PUBKEY_HASH_LEN);
572 			wpa_hexdump(MSG_DEBUG, "WPS: Expected public key hash",
573 				    wps->peer_pubkey_hash,
574 				    WPS_OOB_PUBKEY_HASH_LEN);
575 			wps->config_error = WPS_CFG_PUBLIC_KEY_HASH_MISMATCH;
576 			return -1;
577 		}
578 	}
579 
580 	wpabuf_free(wps->dh_pubkey_r);
581 	wps->dh_pubkey_r = wpabuf_alloc_copy(pk, pk_len);
582 	if (wps->dh_pubkey_r == NULL)
583 		return -1;
584 
585 	if (wps_derive_keys(wps) < 0)
586 		return -1;
587 
588 	return 0;
589 }
590 
591 
592 static int wps_process_r_hash1(struct wps_data *wps, const u8 *r_hash1)
593 {
594 	if (r_hash1 == NULL) {
595 		wpa_printf(MSG_DEBUG, "WPS: No R-Hash1 received");
596 		return -1;
597 	}
598 
599 	os_memcpy(wps->peer_hash1, r_hash1, WPS_HASH_LEN);
600 	wpa_hexdump(MSG_DEBUG, "WPS: R-Hash1", wps->peer_hash1, WPS_HASH_LEN);
601 
602 	return 0;
603 }
604 
605 
606 static int wps_process_r_hash2(struct wps_data *wps, const u8 *r_hash2)
607 {
608 	if (r_hash2 == NULL) {
609 		wpa_printf(MSG_DEBUG, "WPS: No R-Hash2 received");
610 		return -1;
611 	}
612 
613 	os_memcpy(wps->peer_hash2, r_hash2, WPS_HASH_LEN);
614 	wpa_hexdump(MSG_DEBUG, "WPS: R-Hash2", wps->peer_hash2, WPS_HASH_LEN);
615 
616 	return 0;
617 }
618 
619 
620 static int wps_process_r_snonce1(struct wps_data *wps, const u8 *r_snonce1)
621 {
622 	u8 hash[SHA256_MAC_LEN];
623 	const u8 *addr[4];
624 	size_t len[4];
625 
626 	if (r_snonce1 == NULL) {
627 		wpa_printf(MSG_DEBUG, "WPS: No R-SNonce1 received");
628 		return -1;
629 	}
630 
631 	wpa_hexdump_key(MSG_DEBUG, "WPS: R-SNonce1", r_snonce1,
632 			WPS_SECRET_NONCE_LEN);
633 
634 	/* R-Hash1 = HMAC_AuthKey(R-S1 || PSK1 || PK_E || PK_R) */
635 	addr[0] = r_snonce1;
636 	len[0] = WPS_SECRET_NONCE_LEN;
637 	addr[1] = wps->psk1;
638 	len[1] = WPS_PSK_LEN;
639 	addr[2] = wpabuf_head(wps->dh_pubkey_e);
640 	len[2] = wpabuf_len(wps->dh_pubkey_e);
641 	addr[3] = wpabuf_head(wps->dh_pubkey_r);
642 	len[3] = wpabuf_len(wps->dh_pubkey_r);
643 	hmac_sha256_vector(wps->authkey, WPS_AUTHKEY_LEN, 4, addr, len, hash);
644 
645 	if (os_memcmp_const(wps->peer_hash1, hash, WPS_HASH_LEN) != 0) {
646 		wpa_printf(MSG_DEBUG, "WPS: R-Hash1 derived from R-S1 does "
647 			   "not match with the pre-committed value");
648 		wps->config_error = WPS_CFG_DEV_PASSWORD_AUTH_FAILURE;
649 		wps_pwd_auth_fail_event(wps->wps, 1, 1, wps->peer_dev.mac_addr);
650 		return -1;
651 	}
652 
653 	wpa_printf(MSG_DEBUG, "WPS: Registrar proved knowledge of the first "
654 		   "half of the device password");
655 
656 	return 0;
657 }
658 
659 
660 static int wps_process_r_snonce2(struct wps_data *wps, const u8 *r_snonce2)
661 {
662 	u8 hash[SHA256_MAC_LEN];
663 	const u8 *addr[4];
664 	size_t len[4];
665 
666 	if (r_snonce2 == NULL) {
667 		wpa_printf(MSG_DEBUG, "WPS: No R-SNonce2 received");
668 		return -1;
669 	}
670 
671 	wpa_hexdump_key(MSG_DEBUG, "WPS: R-SNonce2", r_snonce2,
672 			WPS_SECRET_NONCE_LEN);
673 
674 	/* R-Hash2 = HMAC_AuthKey(R-S2 || PSK2 || PK_E || PK_R) */
675 	addr[0] = r_snonce2;
676 	len[0] = WPS_SECRET_NONCE_LEN;
677 	addr[1] = wps->psk2;
678 	len[1] = WPS_PSK_LEN;
679 	addr[2] = wpabuf_head(wps->dh_pubkey_e);
680 	len[2] = wpabuf_len(wps->dh_pubkey_e);
681 	addr[3] = wpabuf_head(wps->dh_pubkey_r);
682 	len[3] = wpabuf_len(wps->dh_pubkey_r);
683 	hmac_sha256_vector(wps->authkey, WPS_AUTHKEY_LEN, 4, addr, len, hash);
684 
685 	if (os_memcmp_const(wps->peer_hash2, hash, WPS_HASH_LEN) != 0) {
686 		wpa_printf(MSG_DEBUG, "WPS: R-Hash2 derived from R-S2 does "
687 			   "not match with the pre-committed value");
688 		wps->config_error = WPS_CFG_DEV_PASSWORD_AUTH_FAILURE;
689 		wps_pwd_auth_fail_event(wps->wps, 1, 2, wps->peer_dev.mac_addr);
690 		return -1;
691 	}
692 
693 	wpa_printf(MSG_DEBUG, "WPS: Registrar proved knowledge of the second "
694 		   "half of the device password");
695 
696 	return 0;
697 }
698 
699 
700 static int wps_process_cred_e(struct wps_data *wps, const u8 *cred,
701 			      size_t cred_len, int wps2)
702 {
703 	struct wps_parse_attr attr;
704 	struct wpabuf msg;
705 	int ret = 0;
706 
707 	wpa_printf(MSG_DEBUG, "WPS: Received Credential");
708 	os_memset(&wps->cred, 0, sizeof(wps->cred));
709 	wpabuf_set(&msg, cred, cred_len);
710 	if (wps_parse_msg(&msg, &attr) < 0 ||
711 	    wps_process_cred(&attr, &wps->cred))
712 		return -1;
713 
714 	if (os_memcmp(wps->cred.mac_addr, wps->wps->dev.mac_addr, ETH_ALEN) !=
715 	    0) {
716 		wpa_printf(MSG_DEBUG, "WPS: MAC Address in the Credential ("
717 			   MACSTR ") does not match with own address (" MACSTR
718 			   ")", MAC2STR(wps->cred.mac_addr),
719 			   MAC2STR(wps->wps->dev.mac_addr));
720 		/*
721 		 * In theory, this could be consider fatal error, but there are
722 		 * number of deployed implementations using other address here
723 		 * due to unclarity in the specification. For interoperability
724 		 * reasons, allow this to be processed since we do not really
725 		 * use the MAC Address information for anything.
726 		 */
727 #ifdef CONFIG_WPS_STRICT
728 		if (wps2) {
729 			wpa_printf(MSG_INFO, "WPS: Do not accept incorrect "
730 				   "MAC Address in AP Settings");
731 			return -1;
732 		}
733 #endif /* CONFIG_WPS_STRICT */
734 	}
735 
736 	if (!(wps->cred.encr_type &
737 	      (WPS_ENCR_NONE | WPS_ENCR_TKIP | WPS_ENCR_AES))) {
738 		if (wps->cred.encr_type & WPS_ENCR_WEP) {
739 			wpa_printf(MSG_INFO, "WPS: Reject Credential "
740 				   "due to WEP configuration");
741 			wps->error_indication = WPS_EI_SECURITY_WEP_PROHIBITED;
742 			return -2;
743 		}
744 
745 		wpa_printf(MSG_INFO, "WPS: Reject Credential due to "
746 			   "invalid encr_type 0x%x", wps->cred.encr_type);
747 		return -1;
748 	}
749 
750 	if (wps->wps->cred_cb) {
751 		wps->cred.cred_attr = cred - 4;
752 		wps->cred.cred_attr_len = cred_len + 4;
753 		ret = wps->wps->cred_cb(wps->wps->cb_ctx, &wps->cred);
754 		wps->cred.cred_attr = NULL;
755 		wps->cred.cred_attr_len = 0;
756 	}
757 
758 	return ret;
759 }
760 
761 
762 static int wps_process_creds(struct wps_data *wps, const u8 *cred[],
763 			     u16 cred_len[], unsigned int num_cred, int wps2)
764 {
765 	size_t i;
766 	int ok = 0;
767 
768 	if (wps->wps->ap)
769 		return 0;
770 
771 	if (num_cred == 0) {
772 		wpa_printf(MSG_DEBUG, "WPS: No Credential attributes "
773 			   "received");
774 		return -1;
775 	}
776 
777 	for (i = 0; i < num_cred; i++) {
778 		int res;
779 		res = wps_process_cred_e(wps, cred[i], cred_len[i], wps2);
780 		if (res == 0)
781 			ok++;
782 		else if (res == -2)
783 			wpa_printf(MSG_DEBUG, "WPS: WEP credential skipped");
784 		else
785 			return -1;
786 	}
787 
788 	if (ok == 0) {
789 		wpa_printf(MSG_DEBUG, "WPS: No valid Credential attribute "
790 			   "received");
791 		return -1;
792 	}
793 
794 	return 0;
795 }
796 
797 
798 static int wps_process_ap_settings_e(struct wps_data *wps,
799 				     struct wps_parse_attr *attr,
800 				     struct wpabuf *attrs, int wps2)
801 {
802 	struct wps_credential cred;
803 	int ret = 0;
804 
805 	if (!wps->wps->ap)
806 		return 0;
807 
808 	if (wps_process_ap_settings(attr, &cred) < 0)
809 		return -1;
810 
811 	wpa_printf(MSG_INFO, "WPS: Received new AP configuration from "
812 		   "Registrar");
813 
814 	if (os_memcmp(cred.mac_addr, wps->wps->dev.mac_addr, ETH_ALEN) !=
815 	    0) {
816 		wpa_printf(MSG_DEBUG, "WPS: MAC Address in the AP Settings ("
817 			   MACSTR ") does not match with own address (" MACSTR
818 			   ")", MAC2STR(cred.mac_addr),
819 			   MAC2STR(wps->wps->dev.mac_addr));
820 		/*
821 		 * In theory, this could be consider fatal error, but there are
822 		 * number of deployed implementations using other address here
823 		 * due to unclarity in the specification. For interoperability
824 		 * reasons, allow this to be processed since we do not really
825 		 * use the MAC Address information for anything.
826 		 */
827 #ifdef CONFIG_WPS_STRICT
828 		if (wps2) {
829 			wpa_printf(MSG_INFO, "WPS: Do not accept incorrect "
830 				   "MAC Address in AP Settings");
831 			return -1;
832 		}
833 #endif /* CONFIG_WPS_STRICT */
834 	}
835 
836 	if (!(cred.encr_type & (WPS_ENCR_NONE | WPS_ENCR_TKIP | WPS_ENCR_AES)))
837 	{
838 		if (cred.encr_type & WPS_ENCR_WEP) {
839 			wpa_printf(MSG_INFO, "WPS: Reject new AP settings "
840 				   "due to WEP configuration");
841 			wps->error_indication = WPS_EI_SECURITY_WEP_PROHIBITED;
842 			return -1;
843 		}
844 
845 		wpa_printf(MSG_INFO, "WPS: Reject new AP settings due to "
846 			   "invalid encr_type 0x%x", cred.encr_type);
847 		return -1;
848 	}
849 
850 #ifdef CONFIG_WPS_STRICT
851 	if (wps2) {
852 		if ((cred.encr_type & (WPS_ENCR_TKIP | WPS_ENCR_AES)) ==
853 		    WPS_ENCR_TKIP ||
854 		    (cred.auth_type & (WPS_AUTH_WPAPSK | WPS_AUTH_WPA2PSK)) ==
855 		    WPS_AUTH_WPAPSK) {
856 			wpa_printf(MSG_INFO, "WPS-STRICT: Invalid WSC 2.0 "
857 				   "AP Settings: WPA-Personal/TKIP only");
858 			wps->error_indication =
859 				WPS_EI_SECURITY_TKIP_ONLY_PROHIBITED;
860 			return -1;
861 		}
862 	}
863 #endif /* CONFIG_WPS_STRICT */
864 
865 	if ((cred.encr_type & (WPS_ENCR_TKIP | WPS_ENCR_AES)) == WPS_ENCR_TKIP)
866 	{
867 		wpa_printf(MSG_DEBUG, "WPS: Upgrade encr_type TKIP -> "
868 			   "TKIP+AES");
869 		cred.encr_type |= WPS_ENCR_AES;
870 	}
871 
872 	if ((cred.auth_type & (WPS_AUTH_WPAPSK | WPS_AUTH_WPA2PSK)) ==
873 	    WPS_AUTH_WPAPSK) {
874 		wpa_printf(MSG_DEBUG, "WPS: Upgrade auth_type WPAPSK -> "
875 			   "WPAPSK+WPA2PSK");
876 		cred.auth_type |= WPS_AUTH_WPA2PSK;
877 	}
878 
879 	if (wps->wps->cred_cb) {
880 		cred.cred_attr = wpabuf_head(attrs);
881 		cred.cred_attr_len = wpabuf_len(attrs);
882 		ret = wps->wps->cred_cb(wps->wps->cb_ctx, &cred);
883 	}
884 
885 	return ret;
886 }
887 
888 
889 static int wps_process_dev_pw_id(struct wps_data *wps, const u8 *dev_pw_id)
890 {
891 	u16 id;
892 
893 	if (dev_pw_id == NULL) {
894 		wpa_printf(MSG_DEBUG, "WPS: Device Password ID");
895 		return -1;
896 	}
897 
898 	id = WPA_GET_BE16(dev_pw_id);
899 	if (wps->dev_pw_id == id) {
900 		wpa_printf(MSG_DEBUG, "WPS: Device Password ID %u", id);
901 		return 0;
902 	}
903 
904 #ifdef CONFIG_P2P
905 	if ((id == DEV_PW_DEFAULT &&
906 	     wps->dev_pw_id == DEV_PW_REGISTRAR_SPECIFIED) ||
907 	    (id == DEV_PW_REGISTRAR_SPECIFIED &&
908 	     wps->dev_pw_id == DEV_PW_DEFAULT)) {
909 		/*
910 		 * Common P2P use cases indicate whether the PIN is from the
911 		 * client or GO using Device Password Id in M1/M2 in a way that
912 		 * does not look fully compliant with WSC specification. Anyway,
913 		 * this is deployed and needs to be allowed, so ignore changes
914 		 * between Registrar-Specified and Default PIN.
915 		 */
916 		wpa_printf(MSG_DEBUG, "WPS: Allow PIN Device Password ID "
917 			   "change");
918 		return 0;
919 	}
920 #endif /* CONFIG_P2P */
921 
922 	wpa_printf(MSG_DEBUG, "WPS: Registrar trying to change Device Password "
923 		   "ID from %u to %u", wps->dev_pw_id, id);
924 
925 	if (wps->dev_pw_id == DEV_PW_PUSHBUTTON && id == DEV_PW_DEFAULT) {
926 		wpa_printf(MSG_DEBUG,
927 			   "WPS: Workaround - ignore PBC-to-PIN change");
928 		return 0;
929 	}
930 
931 	if (wps->alt_dev_password && wps->alt_dev_pw_id == id) {
932 		wpa_printf(MSG_DEBUG, "WPS: Found a matching Device Password");
933 		bin_clear_free(wps->dev_password, wps->dev_password_len);
934 		wps->dev_pw_id = wps->alt_dev_pw_id;
935 		wps->dev_password = wps->alt_dev_password;
936 		wps->dev_password_len = wps->alt_dev_password_len;
937 		wps->alt_dev_password = NULL;
938 		wps->alt_dev_password_len = 0;
939 		return 0;
940 	}
941 
942 	return -1;
943 }
944 
945 
946 static enum wps_process_res wps_process_m2(struct wps_data *wps,
947 					   const struct wpabuf *msg,
948 					   struct wps_parse_attr *attr)
949 {
950 	wpa_printf(MSG_DEBUG, "WPS: Received M2");
951 
952 	if (wps->state != RECV_M2) {
953 		wpa_printf(MSG_DEBUG, "WPS: Unexpected state (%d) for "
954 			   "receiving M2", wps->state);
955 		wps->state = SEND_WSC_NACK;
956 		return WPS_CONTINUE;
957 	}
958 
959 	if (wps_process_registrar_nonce(wps, attr->registrar_nonce) ||
960 	    wps_process_enrollee_nonce(wps, attr->enrollee_nonce) ||
961 	    wps_process_uuid_r(wps, attr->uuid_r) ||
962 	    wps_process_dev_pw_id(wps, attr->dev_password_id)) {
963 		wps->state = SEND_WSC_NACK;
964 		return WPS_CONTINUE;
965 	}
966 
967 	/*
968 	 * Stop here on an AP as an Enrollee if AP Setup is locked unless the
969 	 * special locked mode is used to allow protocol run up to M7 in order
970 	 * to support external Registrars that only learn the current AP
971 	 * configuration without changing it.
972 	 */
973 	if (wps->wps->ap &&
974 	    ((wps->wps->ap_setup_locked && wps->wps->ap_setup_locked != 2) ||
975 	     wps->dev_password == NULL)) {
976 		wpa_printf(MSG_DEBUG, "WPS: AP Setup is locked - refuse "
977 			   "registration of a new Registrar");
978 		wps->config_error = WPS_CFG_SETUP_LOCKED;
979 		wps->state = SEND_WSC_NACK;
980 		return WPS_CONTINUE;
981 	}
982 
983 	if (wps_process_pubkey(wps, attr->public_key, attr->public_key_len) ||
984 	    wps_process_authenticator(wps, attr->authenticator, msg) ||
985 	    wps_process_device_attrs(&wps->peer_dev, attr)) {
986 		wps->state = SEND_WSC_NACK;
987 		return WPS_CONTINUE;
988 	}
989 
990 #ifdef CONFIG_WPS_NFC
991 	if (wps->peer_pubkey_hash_set) {
992 		struct wpabuf *decrypted;
993 		struct wps_parse_attr eattr;
994 
995 		decrypted = wps_decrypt_encr_settings(wps, attr->encr_settings,
996 						      attr->encr_settings_len);
997 		if (decrypted == NULL) {
998 			wpa_printf(MSG_DEBUG, "WPS: Failed to decrypt "
999 				   "Encrypted Settings attribute");
1000 			wps->state = SEND_WSC_NACK;
1001 			return WPS_CONTINUE;
1002 		}
1003 
1004 		wpa_printf(MSG_DEBUG, "WPS: Processing decrypted Encrypted "
1005 			   "Settings attribute");
1006 		if (wps_parse_msg(decrypted, &eattr) < 0 ||
1007 		    wps_process_key_wrap_auth(wps, decrypted,
1008 					      eattr.key_wrap_auth) ||
1009 		    wps_process_creds(wps, eattr.cred, eattr.cred_len,
1010 				      eattr.num_cred, attr->version2 != NULL)) {
1011 			wpabuf_clear_free(decrypted);
1012 			wps->state = SEND_WSC_NACK;
1013 			return WPS_CONTINUE;
1014 		}
1015 		wpabuf_clear_free(decrypted);
1016 
1017 		wps->state = WPS_MSG_DONE;
1018 		return WPS_CONTINUE;
1019 	}
1020 #endif /* CONFIG_WPS_NFC */
1021 
1022 	wps->state = SEND_M3;
1023 	return WPS_CONTINUE;
1024 }
1025 
1026 
1027 static enum wps_process_res wps_process_m2d(struct wps_data *wps,
1028 					    struct wps_parse_attr *attr)
1029 {
1030 	wpa_printf(MSG_DEBUG, "WPS: Received M2D");
1031 
1032 	if (wps->state != RECV_M2) {
1033 		wpa_printf(MSG_DEBUG, "WPS: Unexpected state (%d) for "
1034 			   "receiving M2D", wps->state);
1035 		wps->state = SEND_WSC_NACK;
1036 		return WPS_CONTINUE;
1037 	}
1038 
1039 	wpa_hexdump_ascii(MSG_DEBUG, "WPS: Manufacturer",
1040 			  attr->manufacturer, attr->manufacturer_len);
1041 	wpa_hexdump_ascii(MSG_DEBUG, "WPS: Model Name",
1042 			  attr->model_name, attr->model_name_len);
1043 	wpa_hexdump_ascii(MSG_DEBUG, "WPS: Model Number",
1044 			  attr->model_number, attr->model_number_len);
1045 	wpa_hexdump_ascii(MSG_DEBUG, "WPS: Serial Number",
1046 			  attr->serial_number, attr->serial_number_len);
1047 	wpa_hexdump_ascii(MSG_DEBUG, "WPS: Device Name",
1048 			  attr->dev_name, attr->dev_name_len);
1049 
1050 	if (wps->wps->event_cb) {
1051 		union wps_event_data data;
1052 		struct wps_event_m2d *m2d = &data.m2d;
1053 		os_memset(&data, 0, sizeof(data));
1054 		if (attr->config_methods)
1055 			m2d->config_methods =
1056 				WPA_GET_BE16(attr->config_methods);
1057 		m2d->manufacturer = attr->manufacturer;
1058 		m2d->manufacturer_len = attr->manufacturer_len;
1059 		m2d->model_name = attr->model_name;
1060 		m2d->model_name_len = attr->model_name_len;
1061 		m2d->model_number = attr->model_number;
1062 		m2d->model_number_len = attr->model_number_len;
1063 		m2d->serial_number = attr->serial_number;
1064 		m2d->serial_number_len = attr->serial_number_len;
1065 		m2d->dev_name = attr->dev_name;
1066 		m2d->dev_name_len = attr->dev_name_len;
1067 		m2d->primary_dev_type = attr->primary_dev_type;
1068 		if (attr->config_error)
1069 			m2d->config_error =
1070 				WPA_GET_BE16(attr->config_error);
1071 		if (attr->dev_password_id)
1072 			m2d->dev_password_id =
1073 				WPA_GET_BE16(attr->dev_password_id);
1074 		wps->wps->event_cb(wps->wps->cb_ctx, WPS_EV_M2D, &data);
1075 	}
1076 
1077 	wps->state = RECEIVED_M2D;
1078 	return WPS_CONTINUE;
1079 }
1080 
1081 
1082 static enum wps_process_res wps_process_m4(struct wps_data *wps,
1083 					   const struct wpabuf *msg,
1084 					   struct wps_parse_attr *attr)
1085 {
1086 	struct wpabuf *decrypted;
1087 	struct wps_parse_attr eattr;
1088 
1089 	wpa_printf(MSG_DEBUG, "WPS: Received M4");
1090 
1091 	if (wps->state != RECV_M4) {
1092 		wpa_printf(MSG_DEBUG, "WPS: Unexpected state (%d) for "
1093 			   "receiving M4", wps->state);
1094 		wps->state = SEND_WSC_NACK;
1095 		return WPS_CONTINUE;
1096 	}
1097 
1098 	if (wps_process_enrollee_nonce(wps, attr->enrollee_nonce) ||
1099 	    wps_process_authenticator(wps, attr->authenticator, msg) ||
1100 	    wps_process_r_hash1(wps, attr->r_hash1) ||
1101 	    wps_process_r_hash2(wps, attr->r_hash2)) {
1102 		wps->state = SEND_WSC_NACK;
1103 		return WPS_CONTINUE;
1104 	}
1105 
1106 	decrypted = wps_decrypt_encr_settings(wps, attr->encr_settings,
1107 					      attr->encr_settings_len);
1108 	if (decrypted == NULL) {
1109 		wpa_printf(MSG_DEBUG, "WPS: Failed to decrypted Encrypted "
1110 			   "Settings attribute");
1111 		wps->state = SEND_WSC_NACK;
1112 		return WPS_CONTINUE;
1113 	}
1114 
1115 	if (wps_validate_m4_encr(decrypted, attr->version2 != NULL) < 0) {
1116 		wpabuf_clear_free(decrypted);
1117 		wps->state = SEND_WSC_NACK;
1118 		return WPS_CONTINUE;
1119 	}
1120 
1121 	wpa_printf(MSG_DEBUG, "WPS: Processing decrypted Encrypted Settings "
1122 		   "attribute");
1123 	if (wps_parse_msg(decrypted, &eattr) < 0 ||
1124 	    wps_process_key_wrap_auth(wps, decrypted, eattr.key_wrap_auth) ||
1125 	    wps_process_r_snonce1(wps, eattr.r_snonce1)) {
1126 		wpabuf_clear_free(decrypted);
1127 		wps->state = SEND_WSC_NACK;
1128 		return WPS_CONTINUE;
1129 	}
1130 	wpabuf_clear_free(decrypted);
1131 
1132 	wps->state = SEND_M5;
1133 	return WPS_CONTINUE;
1134 }
1135 
1136 
1137 static enum wps_process_res wps_process_m6(struct wps_data *wps,
1138 					   const struct wpabuf *msg,
1139 					   struct wps_parse_attr *attr)
1140 {
1141 	struct wpabuf *decrypted;
1142 	struct wps_parse_attr eattr;
1143 
1144 	wpa_printf(MSG_DEBUG, "WPS: Received M6");
1145 
1146 	if (wps->state != RECV_M6) {
1147 		wpa_printf(MSG_DEBUG, "WPS: Unexpected state (%d) for "
1148 			   "receiving M6", wps->state);
1149 		wps->state = SEND_WSC_NACK;
1150 		return WPS_CONTINUE;
1151 	}
1152 
1153 	if (wps_process_enrollee_nonce(wps, attr->enrollee_nonce) ||
1154 	    wps_process_authenticator(wps, attr->authenticator, msg)) {
1155 		wps->state = SEND_WSC_NACK;
1156 		return WPS_CONTINUE;
1157 	}
1158 
1159 	decrypted = wps_decrypt_encr_settings(wps, attr->encr_settings,
1160 					      attr->encr_settings_len);
1161 	if (decrypted == NULL) {
1162 		wpa_printf(MSG_DEBUG, "WPS: Failed to decrypted Encrypted "
1163 			   "Settings attribute");
1164 		wps->state = SEND_WSC_NACK;
1165 		return WPS_CONTINUE;
1166 	}
1167 
1168 	if (wps_validate_m6_encr(decrypted, attr->version2 != NULL) < 0) {
1169 		wpabuf_clear_free(decrypted);
1170 		wps->state = SEND_WSC_NACK;
1171 		return WPS_CONTINUE;
1172 	}
1173 
1174 	wpa_printf(MSG_DEBUG, "WPS: Processing decrypted Encrypted Settings "
1175 		   "attribute");
1176 	if (wps_parse_msg(decrypted, &eattr) < 0 ||
1177 	    wps_process_key_wrap_auth(wps, decrypted, eattr.key_wrap_auth) ||
1178 	    wps_process_r_snonce2(wps, eattr.r_snonce2)) {
1179 		wpabuf_clear_free(decrypted);
1180 		wps->state = SEND_WSC_NACK;
1181 		return WPS_CONTINUE;
1182 	}
1183 	wpabuf_clear_free(decrypted);
1184 
1185 	if (wps->wps->ap)
1186 		wps->wps->event_cb(wps->wps->cb_ctx, WPS_EV_AP_PIN_SUCCESS,
1187 				   NULL);
1188 
1189 	wps->state = SEND_M7;
1190 	return WPS_CONTINUE;
1191 }
1192 
1193 
1194 static enum wps_process_res wps_process_m8(struct wps_data *wps,
1195 					   const struct wpabuf *msg,
1196 					   struct wps_parse_attr *attr)
1197 {
1198 	struct wpabuf *decrypted;
1199 	struct wps_parse_attr eattr;
1200 
1201 	wpa_printf(MSG_DEBUG, "WPS: Received M8");
1202 
1203 	if (wps->state != RECV_M8) {
1204 		wpa_printf(MSG_DEBUG, "WPS: Unexpected state (%d) for "
1205 			   "receiving M8", wps->state);
1206 		wps->state = SEND_WSC_NACK;
1207 		return WPS_CONTINUE;
1208 	}
1209 
1210 	if (wps_process_enrollee_nonce(wps, attr->enrollee_nonce) ||
1211 	    wps_process_authenticator(wps, attr->authenticator, msg)) {
1212 		wps->state = SEND_WSC_NACK;
1213 		return WPS_CONTINUE;
1214 	}
1215 
1216 	if (wps->wps->ap && wps->wps->ap_setup_locked) {
1217 		/*
1218 		 * Stop here if special ap_setup_locked == 2 mode allowed the
1219 		 * protocol to continue beyond M2. This allows ER to learn the
1220 		 * current AP settings without changing them.
1221 		 */
1222 		wpa_printf(MSG_DEBUG, "WPS: AP Setup is locked - refuse "
1223 			   "registration of a new Registrar");
1224 		wps->config_error = WPS_CFG_SETUP_LOCKED;
1225 		wps->state = SEND_WSC_NACK;
1226 		return WPS_CONTINUE;
1227 	}
1228 
1229 	decrypted = wps_decrypt_encr_settings(wps, attr->encr_settings,
1230 					      attr->encr_settings_len);
1231 	if (decrypted == NULL) {
1232 		wpa_printf(MSG_DEBUG, "WPS: Failed to decrypted Encrypted "
1233 			   "Settings attribute");
1234 		wps->state = SEND_WSC_NACK;
1235 		return WPS_CONTINUE;
1236 	}
1237 
1238 	if (wps_validate_m8_encr(decrypted, wps->wps->ap,
1239 				 attr->version2 != NULL) < 0) {
1240 		wpabuf_clear_free(decrypted);
1241 		wps->state = SEND_WSC_NACK;
1242 		return WPS_CONTINUE;
1243 	}
1244 
1245 	wpa_printf(MSG_DEBUG, "WPS: Processing decrypted Encrypted Settings "
1246 		   "attribute");
1247 	if (wps_parse_msg(decrypted, &eattr) < 0 ||
1248 	    wps_process_key_wrap_auth(wps, decrypted, eattr.key_wrap_auth) ||
1249 	    wps_process_creds(wps, eattr.cred, eattr.cred_len,
1250 			      eattr.num_cred, attr->version2 != NULL) ||
1251 	    wps_process_ap_settings_e(wps, &eattr, decrypted,
1252 				      attr->version2 != NULL)) {
1253 		wpabuf_clear_free(decrypted);
1254 		wps->state = SEND_WSC_NACK;
1255 		return WPS_CONTINUE;
1256 	}
1257 	wpabuf_clear_free(decrypted);
1258 
1259 	wps->state = WPS_MSG_DONE;
1260 	return WPS_CONTINUE;
1261 }
1262 
1263 
1264 static enum wps_process_res wps_process_wsc_msg(struct wps_data *wps,
1265 						const struct wpabuf *msg)
1266 {
1267 	struct wps_parse_attr attr;
1268 	enum wps_process_res ret = WPS_CONTINUE;
1269 
1270 	wpa_printf(MSG_DEBUG, "WPS: Received WSC_MSG");
1271 
1272 	if (wps_parse_msg(msg, &attr) < 0)
1273 		return WPS_FAILURE;
1274 
1275 	if (attr.enrollee_nonce == NULL ||
1276 	    os_memcmp(wps->nonce_e, attr.enrollee_nonce, WPS_NONCE_LEN) != 0) {
1277 		wpa_printf(MSG_DEBUG, "WPS: Mismatch in enrollee nonce");
1278 		return WPS_FAILURE;
1279 	}
1280 
1281 	if (attr.msg_type == NULL) {
1282 		wpa_printf(MSG_DEBUG, "WPS: No Message Type attribute");
1283 		wps->state = SEND_WSC_NACK;
1284 		return WPS_CONTINUE;
1285 	}
1286 
1287 	switch (*attr.msg_type) {
1288 	case WPS_M2:
1289 		if (wps_validate_m2(msg) < 0)
1290 			return WPS_FAILURE;
1291 		ret = wps_process_m2(wps, msg, &attr);
1292 		break;
1293 	case WPS_M2D:
1294 		if (wps_validate_m2d(msg) < 0)
1295 			return WPS_FAILURE;
1296 		ret = wps_process_m2d(wps, &attr);
1297 		break;
1298 	case WPS_M4:
1299 		if (wps_validate_m4(msg) < 0)
1300 			return WPS_FAILURE;
1301 		ret = wps_process_m4(wps, msg, &attr);
1302 		if (ret == WPS_FAILURE || wps->state == SEND_WSC_NACK)
1303 			wps_fail_event(wps->wps, WPS_M4, wps->config_error,
1304 				       wps->error_indication,
1305 				       wps->peer_dev.mac_addr);
1306 		break;
1307 	case WPS_M6:
1308 		if (wps_validate_m6(msg) < 0)
1309 			return WPS_FAILURE;
1310 		ret = wps_process_m6(wps, msg, &attr);
1311 		if (ret == WPS_FAILURE || wps->state == SEND_WSC_NACK)
1312 			wps_fail_event(wps->wps, WPS_M6, wps->config_error,
1313 				       wps->error_indication,
1314 				       wps->peer_dev.mac_addr);
1315 		break;
1316 	case WPS_M8:
1317 		if (wps_validate_m8(msg) < 0)
1318 			return WPS_FAILURE;
1319 		ret = wps_process_m8(wps, msg, &attr);
1320 		if (ret == WPS_FAILURE || wps->state == SEND_WSC_NACK)
1321 			wps_fail_event(wps->wps, WPS_M8, wps->config_error,
1322 				       wps->error_indication,
1323 				       wps->peer_dev.mac_addr);
1324 		break;
1325 	default:
1326 		wpa_printf(MSG_DEBUG, "WPS: Unsupported Message Type %d",
1327 			   *attr.msg_type);
1328 		return WPS_FAILURE;
1329 	}
1330 
1331 	/*
1332 	 * Save a copy of the last message for Authenticator derivation if we
1333 	 * are continuing. However, skip M2D since it is not authenticated and
1334 	 * neither is the ACK/NACK response frame. This allows the possibly
1335 	 * following M2 to be processed correctly by using the previously sent
1336 	 * M1 in Authenticator derivation.
1337 	 */
1338 	if (ret == WPS_CONTINUE && *attr.msg_type != WPS_M2D) {
1339 		/* Save a copy of the last message for Authenticator derivation
1340 		 */
1341 		wpabuf_free(wps->last_msg);
1342 		wps->last_msg = wpabuf_dup(msg);
1343 	}
1344 
1345 	return ret;
1346 }
1347 
1348 
1349 static enum wps_process_res wps_process_wsc_ack(struct wps_data *wps,
1350 						const struct wpabuf *msg)
1351 {
1352 	struct wps_parse_attr attr;
1353 
1354 	wpa_printf(MSG_DEBUG, "WPS: Received WSC_ACK");
1355 
1356 	if (wps_parse_msg(msg, &attr) < 0)
1357 		return WPS_FAILURE;
1358 
1359 	if (attr.msg_type == NULL) {
1360 		wpa_printf(MSG_DEBUG, "WPS: No Message Type attribute");
1361 		return WPS_FAILURE;
1362 	}
1363 
1364 	if (*attr.msg_type != WPS_WSC_ACK) {
1365 		wpa_printf(MSG_DEBUG, "WPS: Invalid Message Type %d",
1366 			   *attr.msg_type);
1367 		return WPS_FAILURE;
1368 	}
1369 
1370 	if (attr.registrar_nonce == NULL ||
1371 	    os_memcmp(wps->nonce_r, attr.registrar_nonce, WPS_NONCE_LEN) != 0)
1372 	{
1373 		wpa_printf(MSG_DEBUG, "WPS: Mismatch in registrar nonce");
1374 		return WPS_FAILURE;
1375 	}
1376 
1377 	if (attr.enrollee_nonce == NULL ||
1378 	    os_memcmp(wps->nonce_e, attr.enrollee_nonce, WPS_NONCE_LEN) != 0) {
1379 		wpa_printf(MSG_DEBUG, "WPS: Mismatch in enrollee nonce");
1380 		return WPS_FAILURE;
1381 	}
1382 
1383 	if (wps->state == RECV_ACK && wps->wps->ap) {
1384 		wpa_printf(MSG_DEBUG, "WPS: External Registrar registration "
1385 			   "completed successfully");
1386 		wps_success_event(wps->wps, wps->peer_dev.mac_addr);
1387 		wps->state = WPS_FINISHED;
1388 		return WPS_DONE;
1389 	}
1390 
1391 	return WPS_FAILURE;
1392 }
1393 
1394 
1395 static enum wps_process_res wps_process_wsc_nack(struct wps_data *wps,
1396 						 const struct wpabuf *msg)
1397 {
1398 	struct wps_parse_attr attr;
1399 	u16 config_error;
1400 
1401 	wpa_printf(MSG_DEBUG, "WPS: Received WSC_NACK");
1402 
1403 	if (wps_parse_msg(msg, &attr) < 0)
1404 		return WPS_FAILURE;
1405 
1406 	if (attr.msg_type == NULL) {
1407 		wpa_printf(MSG_DEBUG, "WPS: No Message Type attribute");
1408 		return WPS_FAILURE;
1409 	}
1410 
1411 	if (*attr.msg_type != WPS_WSC_NACK) {
1412 		wpa_printf(MSG_DEBUG, "WPS: Invalid Message Type %d",
1413 			   *attr.msg_type);
1414 		return WPS_FAILURE;
1415 	}
1416 
1417 	if (attr.registrar_nonce == NULL ||
1418 	    os_memcmp(wps->nonce_r, attr.registrar_nonce, WPS_NONCE_LEN) != 0)
1419 	{
1420 		wpa_printf(MSG_DEBUG, "WPS: Mismatch in registrar nonce");
1421 		wpa_hexdump(MSG_DEBUG, "WPS: Received Registrar Nonce",
1422 			    attr.registrar_nonce, WPS_NONCE_LEN);
1423 		wpa_hexdump(MSG_DEBUG, "WPS: Expected Registrar Nonce",
1424 			    wps->nonce_r, WPS_NONCE_LEN);
1425 		return WPS_FAILURE;
1426 	}
1427 
1428 	if (attr.enrollee_nonce == NULL ||
1429 	    os_memcmp(wps->nonce_e, attr.enrollee_nonce, WPS_NONCE_LEN) != 0) {
1430 		wpa_printf(MSG_DEBUG, "WPS: Mismatch in enrollee nonce");
1431 		wpa_hexdump(MSG_DEBUG, "WPS: Received Enrollee Nonce",
1432 			    attr.enrollee_nonce, WPS_NONCE_LEN);
1433 		wpa_hexdump(MSG_DEBUG, "WPS: Expected Enrollee Nonce",
1434 			    wps->nonce_e, WPS_NONCE_LEN);
1435 		return WPS_FAILURE;
1436 	}
1437 
1438 	if (attr.config_error == NULL) {
1439 		wpa_printf(MSG_DEBUG, "WPS: No Configuration Error attribute "
1440 			   "in WSC_NACK");
1441 		return WPS_FAILURE;
1442 	}
1443 
1444 	config_error = WPA_GET_BE16(attr.config_error);
1445 	wpa_printf(MSG_DEBUG, "WPS: Registrar terminated negotiation with "
1446 		   "Configuration Error %d", config_error);
1447 
1448 	switch (wps->state) {
1449 	case RECV_M4:
1450 		wps_fail_event(wps->wps, WPS_M3, config_error,
1451 			       wps->error_indication, wps->peer_dev.mac_addr);
1452 		break;
1453 	case RECV_M6:
1454 		wps_fail_event(wps->wps, WPS_M5, config_error,
1455 			       wps->error_indication, wps->peer_dev.mac_addr);
1456 		break;
1457 	case RECV_M8:
1458 		wps_fail_event(wps->wps, WPS_M7, config_error,
1459 			       wps->error_indication, wps->peer_dev.mac_addr);
1460 		break;
1461 	default:
1462 		break;
1463 	}
1464 
1465 	/* Followed by NACK if Enrollee is Supplicant or EAP-Failure if
1466 	 * Enrollee is Authenticator */
1467 	wps->state = SEND_WSC_NACK;
1468 
1469 	return WPS_FAILURE;
1470 }
1471 
1472 
1473 enum wps_process_res wps_enrollee_process_msg(struct wps_data *wps,
1474 					      enum wsc_op_code op_code,
1475 					      const struct wpabuf *msg)
1476 {
1477 
1478 	wpa_printf(MSG_DEBUG, "WPS: Processing received message (len=%lu "
1479 		   "op_code=%d)",
1480 		   (unsigned long) wpabuf_len(msg), op_code);
1481 
1482 	if (op_code == WSC_UPnP) {
1483 		/* Determine the OpCode based on message type attribute */
1484 		struct wps_parse_attr attr;
1485 		if (wps_parse_msg(msg, &attr) == 0 && attr.msg_type) {
1486 			if (*attr.msg_type == WPS_WSC_ACK)
1487 				op_code = WSC_ACK;
1488 			else if (*attr.msg_type == WPS_WSC_NACK)
1489 				op_code = WSC_NACK;
1490 		}
1491 	}
1492 
1493 	switch (op_code) {
1494 	case WSC_MSG:
1495 	case WSC_UPnP:
1496 		return wps_process_wsc_msg(wps, msg);
1497 	case WSC_ACK:
1498 		if (wps_validate_wsc_ack(msg) < 0)
1499 			return WPS_FAILURE;
1500 		return wps_process_wsc_ack(wps, msg);
1501 	case WSC_NACK:
1502 		if (wps_validate_wsc_nack(msg) < 0)
1503 			return WPS_FAILURE;
1504 		return wps_process_wsc_nack(wps, msg);
1505 	default:
1506 		wpa_printf(MSG_DEBUG, "WPS: Unsupported op_code %d", op_code);
1507 		return WPS_FAILURE;
1508 	}
1509 }
1510