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      1 /*
      2  * Wi-Fi Protected Setup - Enrollee
      3  * Copyright (c) 2008, Jouni Malinen <j (at) 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 	u8 multi_ap_backhaul_sta = 0;
    109 
    110 	if (random_get_bytes(wps->nonce_e, WPS_NONCE_LEN) < 0)
    111 		return NULL;
    112 	wpa_hexdump(MSG_DEBUG, "WPS: Enrollee Nonce",
    113 		    wps->nonce_e, WPS_NONCE_LEN);
    114 
    115 	wpa_printf(MSG_DEBUG, "WPS: Building Message M1");
    116 	msg = wpabuf_alloc(1000);
    117 	if (msg == NULL)
    118 		return NULL;
    119 
    120 	config_methods = wps->wps->config_methods;
    121 	if (wps->wps->ap && !wps->pbc_in_m1 &&
    122 	    (wps->dev_password_len != 0 ||
    123 	     (config_methods & WPS_CONFIG_DISPLAY))) {
    124 		/*
    125 		 * These are the methods that the AP supports as an Enrollee
    126 		 * for adding external Registrars, so remove PushButton.
    127 		 *
    128 		 * As a workaround for Windows 7 mechanism for probing WPS
    129 		 * capabilities from M1, leave PushButton option if no PIN
    130 		 * method is available or if WPS configuration enables PBC
    131 		 * workaround.
    132 		 */
    133 		config_methods &= ~WPS_CONFIG_PUSHBUTTON;
    134 		config_methods &= ~(WPS_CONFIG_VIRT_PUSHBUTTON |
    135 				    WPS_CONFIG_PHY_PUSHBUTTON);
    136 	}
    137 
    138 	if (wps->multi_ap_backhaul_sta)
    139 		multi_ap_backhaul_sta = MULTI_AP_BACKHAUL_STA;
    140 
    141 	if (wps_build_version(msg) ||
    142 	    wps_build_msg_type(msg, WPS_M1) ||
    143 	    wps_build_uuid_e(msg, wps->uuid_e) ||
    144 	    wps_build_mac_addr(msg, wps->mac_addr_e) ||
    145 	    wps_build_enrollee_nonce(wps, msg) ||
    146 	    wps_build_public_key(wps, msg) ||
    147 	    wps_build_auth_type_flags(wps, msg) ||
    148 	    wps_build_encr_type_flags(wps, msg) ||
    149 	    wps_build_conn_type_flags(wps, msg) ||
    150 	    wps_build_config_methods(msg, config_methods) ||
    151 	    wps_build_wps_state(wps, msg) ||
    152 	    wps_build_device_attrs(&wps->wps->dev, msg) ||
    153 	    wps_build_rf_bands(&wps->wps->dev, msg,
    154 			       wps->wps->rf_band_cb(wps->wps->cb_ctx)) ||
    155 	    wps_build_assoc_state(wps, msg) ||
    156 	    wps_build_dev_password_id(msg, wps->dev_pw_id) ||
    157 	    wps_build_config_error(msg, WPS_CFG_NO_ERROR) ||
    158 	    wps_build_os_version(&wps->wps->dev, msg) ||
    159 	    wps_build_wfa_ext(msg, 0, NULL, 0, multi_ap_backhaul_sta) ||
    160 	    wps_build_vendor_ext_m1(&wps->wps->dev, msg)) {
    161 		wpabuf_free(msg);
    162 		return NULL;
    163 	}
    164 
    165 	wps->state = RECV_M2;
    166 	return msg;
    167 }
    168 
    169 
    170 static struct wpabuf * wps_build_m3(struct wps_data *wps)
    171 {
    172 	struct wpabuf *msg;
    173 
    174 	wpa_printf(MSG_DEBUG, "WPS: Building Message M3");
    175 
    176 	if (wps->dev_password == NULL) {
    177 		wpa_printf(MSG_DEBUG, "WPS: No Device Password available");
    178 		return NULL;
    179 	}
    180 	if (wps_derive_psk(wps, wps->dev_password, wps->dev_password_len) < 0)
    181 		return NULL;
    182 
    183 	if (wps->wps->ap && random_pool_ready() != 1) {
    184 		wpa_printf(MSG_INFO,
    185 			   "WPS: Not enough entropy in random pool to proceed - do not allow AP PIN to be used");
    186 		return NULL;
    187 	}
    188 
    189 	msg = wpabuf_alloc(1000);
    190 	if (msg == NULL)
    191 		return NULL;
    192 
    193 	if (wps_build_version(msg) ||
    194 	    wps_build_msg_type(msg, WPS_M3) ||
    195 	    wps_build_registrar_nonce(wps, msg) ||
    196 	    wps_build_e_hash(wps, msg) ||
    197 	    wps_build_wfa_ext(msg, 0, NULL, 0, 0) ||
    198 	    wps_build_authenticator(wps, msg)) {
    199 		wpabuf_free(msg);
    200 		return NULL;
    201 	}
    202 
    203 	wps->state = RECV_M4;
    204 	return msg;
    205 }
    206 
    207 
    208 static struct wpabuf * wps_build_m5(struct wps_data *wps)
    209 {
    210 	struct wpabuf *msg, *plain;
    211 
    212 	wpa_printf(MSG_DEBUG, "WPS: Building Message M5");
    213 
    214 	plain = wpabuf_alloc(200);
    215 	if (plain == NULL)
    216 		return NULL;
    217 
    218 	msg = wpabuf_alloc(1000);
    219 	if (msg == NULL) {
    220 		wpabuf_free(plain);
    221 		return NULL;
    222 	}
    223 
    224 	if (wps_build_version(msg) ||
    225 	    wps_build_msg_type(msg, WPS_M5) ||
    226 	    wps_build_registrar_nonce(wps, msg) ||
    227 	    wps_build_e_snonce1(wps, plain) ||
    228 	    wps_build_key_wrap_auth(wps, plain) ||
    229 	    wps_build_encr_settings(wps, msg, plain) ||
    230 	    wps_build_wfa_ext(msg, 0, NULL, 0, 0) ||
    231 	    wps_build_authenticator(wps, msg)) {
    232 		wpabuf_clear_free(plain);
    233 		wpabuf_free(msg);
    234 		return NULL;
    235 	}
    236 	wpabuf_clear_free(plain);
    237 
    238 	wps->state = RECV_M6;
    239 	return msg;
    240 }
    241 
    242 
    243 static int wps_build_cred_ssid(struct wps_data *wps, struct wpabuf *msg)
    244 {
    245 	wpa_printf(MSG_DEBUG, "WPS:  * SSID");
    246 	wpabuf_put_be16(msg, ATTR_SSID);
    247 	wpabuf_put_be16(msg, wps->wps->ssid_len);
    248 	wpabuf_put_data(msg, wps->wps->ssid, wps->wps->ssid_len);
    249 	return 0;
    250 }
    251 
    252 
    253 static int wps_build_cred_auth_type(struct wps_data *wps, struct wpabuf *msg)
    254 {
    255 	u16 auth_type = wps->wps->ap_auth_type;
    256 
    257 	/*
    258 	 * Work around issues with Windows 7 WPS implementation not liking
    259 	 * multiple Authentication Type bits in M7 AP Settings attribute by
    260 	 * showing only the most secure option from current configuration.
    261 	 */
    262 	if (auth_type & WPS_AUTH_WPA2PSK)
    263 		auth_type = WPS_AUTH_WPA2PSK;
    264 	else if (auth_type & WPS_AUTH_WPAPSK)
    265 		auth_type = WPS_AUTH_WPAPSK;
    266 	else if (auth_type & WPS_AUTH_OPEN)
    267 		auth_type = WPS_AUTH_OPEN;
    268 
    269 	wpa_printf(MSG_DEBUG, "WPS:  * Authentication Type (0x%x)", auth_type);
    270 	wpabuf_put_be16(msg, ATTR_AUTH_TYPE);
    271 	wpabuf_put_be16(msg, 2);
    272 	wpabuf_put_be16(msg, auth_type);
    273 	return 0;
    274 }
    275 
    276 
    277 static int wps_build_cred_encr_type(struct wps_data *wps, struct wpabuf *msg)
    278 {
    279 	u16 encr_type = wps->wps->ap_encr_type;
    280 
    281 	/*
    282 	 * Work around issues with Windows 7 WPS implementation not liking
    283 	 * multiple Encryption Type bits in M7 AP Settings attribute by
    284 	 * showing only the most secure option from current configuration.
    285 	 */
    286 	if (wps->wps->ap_auth_type & (WPS_AUTH_WPA2PSK | WPS_AUTH_WPAPSK)) {
    287 		if (encr_type & WPS_ENCR_AES)
    288 			encr_type = WPS_ENCR_AES;
    289 		else if (encr_type & WPS_ENCR_TKIP)
    290 			encr_type = WPS_ENCR_TKIP;
    291 	}
    292 
    293 	wpa_printf(MSG_DEBUG, "WPS:  * Encryption Type (0x%x)", encr_type);
    294 	wpabuf_put_be16(msg, ATTR_ENCR_TYPE);
    295 	wpabuf_put_be16(msg, 2);
    296 	wpabuf_put_be16(msg, encr_type);
    297 	return 0;
    298 }
    299 
    300 
    301 static int wps_build_cred_network_key(struct wps_data *wps, struct wpabuf *msg)
    302 {
    303 	if ((wps->wps->ap_auth_type & (WPS_AUTH_WPAPSK | WPS_AUTH_WPA2PSK)) &&
    304 	    wps->wps->network_key_len == 0) {
    305 		char hex[65];
    306 		u8 psk[32];
    307 		/* Generate a random per-device PSK */
    308 		if (random_pool_ready() != 1 ||
    309 		    random_get_bytes(psk, sizeof(psk)) < 0) {
    310 			wpa_printf(MSG_INFO,
    311 				   "WPS: Could not generate random PSK");
    312 			return -1;
    313 		}
    314 		wpa_hexdump_key(MSG_DEBUG, "WPS: Generated per-device PSK",
    315 				psk, sizeof(psk));
    316 		wpa_printf(MSG_DEBUG, "WPS:  * Network Key (len=%u)",
    317 			   (unsigned int) wps->new_psk_len * 2);
    318 		wpa_snprintf_hex(hex, sizeof(hex), psk, sizeof(psk));
    319 		wpabuf_put_be16(msg, ATTR_NETWORK_KEY);
    320 		wpabuf_put_be16(msg, sizeof(psk) * 2);
    321 		wpabuf_put_data(msg, hex, sizeof(psk) * 2);
    322 		if (wps->wps->registrar) {
    323 			wps_cb_new_psk(wps->wps->registrar,
    324 				       wps->peer_dev.mac_addr,
    325 				       wps->p2p_dev_addr, psk, sizeof(psk));
    326 		}
    327 		return 0;
    328 	}
    329 
    330 	wpa_printf(MSG_DEBUG, "WPS:  * Network Key (len=%u)",
    331 		   (unsigned int) wps->wps->network_key_len);
    332 	wpabuf_put_be16(msg, ATTR_NETWORK_KEY);
    333 	wpabuf_put_be16(msg, wps->wps->network_key_len);
    334 	wpabuf_put_data(msg, wps->wps->network_key, wps->wps->network_key_len);
    335 	return 0;
    336 }
    337 
    338 
    339 static int wps_build_cred_mac_addr(struct wps_data *wps, struct wpabuf *msg)
    340 {
    341 	wpa_printf(MSG_DEBUG, "WPS:  * MAC Address (AP BSSID)");
    342 	wpabuf_put_be16(msg, ATTR_MAC_ADDR);
    343 	wpabuf_put_be16(msg, ETH_ALEN);
    344 	wpabuf_put_data(msg, wps->wps->dev.mac_addr, ETH_ALEN);
    345 	return 0;
    346 }
    347 
    348 
    349 static int wps_build_ap_settings(struct wps_data *wps, struct wpabuf *plain)
    350 {
    351 	const u8 *start, *end;
    352 	int ret;
    353 
    354 	if (wps->wps->ap_settings) {
    355 		wpa_printf(MSG_DEBUG, "WPS:  * AP Settings (pre-configured)");
    356 		wpabuf_put_data(plain, wps->wps->ap_settings,
    357 				wps->wps->ap_settings_len);
    358 		return 0;
    359 	}
    360 
    361 	wpa_printf(MSG_DEBUG, "WPS:  * AP Settings based on current configuration");
    362 	start = wpabuf_put(plain, 0);
    363 	ret = wps_build_cred_ssid(wps, plain) ||
    364 		wps_build_cred_mac_addr(wps, plain) ||
    365 		wps_build_cred_auth_type(wps, plain) ||
    366 		wps_build_cred_encr_type(wps, plain) ||
    367 		wps_build_cred_network_key(wps, plain);
    368 	end = wpabuf_put(plain, 0);
    369 
    370 	wpa_hexdump_key(MSG_DEBUG, "WPS: Plaintext AP Settings",
    371 			start, end - start);
    372 
    373 	return ret;
    374 }
    375 
    376 
    377 static struct wpabuf * wps_build_m7(struct wps_data *wps)
    378 {
    379 	struct wpabuf *msg, *plain;
    380 
    381 	wpa_printf(MSG_DEBUG, "WPS: Building Message M7");
    382 
    383 	plain = wpabuf_alloc(500 + wps->wps->ap_settings_len);
    384 	if (plain == NULL)
    385 		return NULL;
    386 
    387 	msg = wpabuf_alloc(1000 + wps->wps->ap_settings_len);
    388 	if (msg == NULL) {
    389 		wpabuf_free(plain);
    390 		return NULL;
    391 	}
    392 
    393 	if (wps_build_version(msg) ||
    394 	    wps_build_msg_type(msg, WPS_M7) ||
    395 	    wps_build_registrar_nonce(wps, msg) ||
    396 	    wps_build_e_snonce2(wps, plain) ||
    397 	    (wps->wps->ap && wps_build_ap_settings(wps, plain)) ||
    398 	    wps_build_key_wrap_auth(wps, plain) ||
    399 	    wps_build_encr_settings(wps, msg, plain) ||
    400 	    wps_build_wfa_ext(msg, 0, NULL, 0, 0) ||
    401 	    wps_build_authenticator(wps, msg)) {
    402 		wpabuf_clear_free(plain);
    403 		wpabuf_free(msg);
    404 		return NULL;
    405 	}
    406 	wpabuf_clear_free(plain);
    407 
    408 	if (wps->wps->ap && wps->wps->registrar) {
    409 		/*
    410 		 * If the Registrar is only learning our current configuration,
    411 		 * it may not continue protocol run to successful completion.
    412 		 * Store information here to make sure it remains available.
    413 		 */
    414 		wps_device_store(wps->wps->registrar, &wps->peer_dev,
    415 				 wps->uuid_r);
    416 	}
    417 
    418 	wps->state = RECV_M8;
    419 	return msg;
    420 }
    421 
    422 
    423 static struct wpabuf * wps_build_wsc_done(struct wps_data *wps)
    424 {
    425 	struct wpabuf *msg;
    426 
    427 	wpa_printf(MSG_DEBUG, "WPS: Building Message WSC_Done");
    428 
    429 	msg = wpabuf_alloc(1000);
    430 	if (msg == NULL)
    431 		return NULL;
    432 
    433 	if (wps_build_version(msg) ||
    434 	    wps_build_msg_type(msg, WPS_WSC_DONE) ||
    435 	    wps_build_enrollee_nonce(wps, msg) ||
    436 	    wps_build_registrar_nonce(wps, msg) ||
    437 	    wps_build_wfa_ext(msg, 0, NULL, 0, 0)) {
    438 		wpabuf_free(msg);
    439 		return NULL;
    440 	}
    441 
    442 	if (wps->wps->ap)
    443 		wps->state = RECV_ACK;
    444 	else {
    445 		wps_success_event(wps->wps, wps->peer_dev.mac_addr);
    446 		wps->state = WPS_FINISHED;
    447 	}
    448 	return msg;
    449 }
    450 
    451 
    452 struct wpabuf * wps_enrollee_get_msg(struct wps_data *wps,
    453 				     enum wsc_op_code *op_code)
    454 {
    455 	struct wpabuf *msg;
    456 
    457 	switch (wps->state) {
    458 	case SEND_M1:
    459 		msg = wps_build_m1(wps);
    460 		*op_code = WSC_MSG;
    461 		break;
    462 	case SEND_M3:
    463 		msg = wps_build_m3(wps);
    464 		*op_code = WSC_MSG;
    465 		break;
    466 	case SEND_M5:
    467 		msg = wps_build_m5(wps);
    468 		*op_code = WSC_MSG;
    469 		break;
    470 	case SEND_M7:
    471 		msg = wps_build_m7(wps);
    472 		*op_code = WSC_MSG;
    473 		break;
    474 	case RECEIVED_M2D:
    475 		if (wps->wps->ap) {
    476 			msg = wps_build_wsc_nack(wps);
    477 			*op_code = WSC_NACK;
    478 			break;
    479 		}
    480 		msg = wps_build_wsc_ack(wps);
    481 		*op_code = WSC_ACK;
    482 		if (msg) {
    483 			/* Another M2/M2D may be received */
    484 			wps->state = RECV_M2;
    485 		}
    486 		break;
    487 	case SEND_WSC_NACK:
    488 		msg = wps_build_wsc_nack(wps);
    489 		*op_code = WSC_NACK;
    490 		break;
    491 	case WPS_MSG_DONE:
    492 		msg = wps_build_wsc_done(wps);
    493 		*op_code = WSC_Done;
    494 		break;
    495 	default:
    496 		wpa_printf(MSG_DEBUG, "WPS: Unsupported state %d for building "
    497 			   "a message", wps->state);
    498 		msg = NULL;
    499 		break;
    500 	}
    501 
    502 	if (*op_code == WSC_MSG && msg) {
    503 		/* Save a copy of the last message for Authenticator derivation
    504 		 */
    505 		wpabuf_free(wps->last_msg);
    506 		wps->last_msg = wpabuf_dup(msg);
    507 	}
    508 
    509 	return msg;
    510 }
    511 
    512 
    513 static int wps_process_registrar_nonce(struct wps_data *wps, const u8 *r_nonce)
    514 {
    515 	if (r_nonce == NULL) {
    516 		wpa_printf(MSG_DEBUG, "WPS: No Registrar Nonce received");
    517 		return -1;
    518 	}
    519 
    520 	os_memcpy(wps->nonce_r, r_nonce, WPS_NONCE_LEN);
    521 	wpa_hexdump(MSG_DEBUG, "WPS: Registrar Nonce",
    522 		    wps->nonce_r, WPS_NONCE_LEN);
    523 
    524 	return 0;
    525 }
    526 
    527 
    528 static int wps_process_enrollee_nonce(struct wps_data *wps, const u8 *e_nonce)
    529 {
    530 	if (e_nonce == NULL) {
    531 		wpa_printf(MSG_DEBUG, "WPS: No Enrollee Nonce received");
    532 		return -1;
    533 	}
    534 
    535 	if (os_memcmp(wps->nonce_e, e_nonce, WPS_NONCE_LEN) != 0) {
    536 		wpa_printf(MSG_DEBUG, "WPS: Invalid Enrollee Nonce received");
    537 		return -1;
    538 	}
    539 
    540 	return 0;
    541 }
    542 
    543 
    544 static int wps_process_uuid_r(struct wps_data *wps, const u8 *uuid_r)
    545 {
    546 	if (uuid_r == NULL) {
    547 		wpa_printf(MSG_DEBUG, "WPS: No UUID-R received");
    548 		return -1;
    549 	}
    550 
    551 	os_memcpy(wps->uuid_r, uuid_r, WPS_UUID_LEN);
    552 	wpa_hexdump(MSG_DEBUG, "WPS: UUID-R", wps->uuid_r, WPS_UUID_LEN);
    553 
    554 	return 0;
    555 }
    556 
    557 
    558 static int wps_process_pubkey(struct wps_data *wps, const u8 *pk,
    559 			      size_t pk_len)
    560 {
    561 	if (pk == NULL || pk_len == 0) {
    562 		wpa_printf(MSG_DEBUG, "WPS: No Public Key received");
    563 		return -1;
    564 	}
    565 
    566 	if (wps->peer_pubkey_hash_set) {
    567 		u8 hash[WPS_HASH_LEN];
    568 		sha256_vector(1, &pk, &pk_len, hash);
    569 		if (os_memcmp_const(hash, wps->peer_pubkey_hash,
    570 				    WPS_OOB_PUBKEY_HASH_LEN) != 0) {
    571 			wpa_printf(MSG_ERROR, "WPS: Public Key hash mismatch");
    572 			wpa_hexdump(MSG_DEBUG, "WPS: Received public key",
    573 				    pk, pk_len);
    574 			wpa_hexdump(MSG_DEBUG, "WPS: Calculated public key "
    575 				    "hash", hash, WPS_OOB_PUBKEY_HASH_LEN);
    576 			wpa_hexdump(MSG_DEBUG, "WPS: Expected public key hash",
    577 				    wps->peer_pubkey_hash,
    578 				    WPS_OOB_PUBKEY_HASH_LEN);
    579 			wps->config_error = WPS_CFG_PUBLIC_KEY_HASH_MISMATCH;
    580 			return -1;
    581 		}
    582 	}
    583 
    584 	wpabuf_free(wps->dh_pubkey_r);
    585 	wps->dh_pubkey_r = wpabuf_alloc_copy(pk, pk_len);
    586 	if (wps->dh_pubkey_r == NULL)
    587 		return -1;
    588 
    589 	if (wps_derive_keys(wps) < 0)
    590 		return -1;
    591 
    592 	return 0;
    593 }
    594 
    595 
    596 static int wps_process_r_hash1(struct wps_data *wps, const u8 *r_hash1)
    597 {
    598 	if (r_hash1 == NULL) {
    599 		wpa_printf(MSG_DEBUG, "WPS: No R-Hash1 received");
    600 		return -1;
    601 	}
    602 
    603 	os_memcpy(wps->peer_hash1, r_hash1, WPS_HASH_LEN);
    604 	wpa_hexdump(MSG_DEBUG, "WPS: R-Hash1", wps->peer_hash1, WPS_HASH_LEN);
    605 
    606 	return 0;
    607 }
    608 
    609 
    610 static int wps_process_r_hash2(struct wps_data *wps, const u8 *r_hash2)
    611 {
    612 	if (r_hash2 == NULL) {
    613 		wpa_printf(MSG_DEBUG, "WPS: No R-Hash2 received");
    614 		return -1;
    615 	}
    616 
    617 	os_memcpy(wps->peer_hash2, r_hash2, WPS_HASH_LEN);
    618 	wpa_hexdump(MSG_DEBUG, "WPS: R-Hash2", wps->peer_hash2, WPS_HASH_LEN);
    619 
    620 	return 0;
    621 }
    622 
    623 
    624 static int wps_process_r_snonce1(struct wps_data *wps, const u8 *r_snonce1)
    625 {
    626 	u8 hash[SHA256_MAC_LEN];
    627 	const u8 *addr[4];
    628 	size_t len[4];
    629 
    630 	if (r_snonce1 == NULL) {
    631 		wpa_printf(MSG_DEBUG, "WPS: No R-SNonce1 received");
    632 		return -1;
    633 	}
    634 
    635 	wpa_hexdump_key(MSG_DEBUG, "WPS: R-SNonce1", r_snonce1,
    636 			WPS_SECRET_NONCE_LEN);
    637 
    638 	/* R-Hash1 = HMAC_AuthKey(R-S1 || PSK1 || PK_E || PK_R) */
    639 	addr[0] = r_snonce1;
    640 	len[0] = WPS_SECRET_NONCE_LEN;
    641 	addr[1] = wps->psk1;
    642 	len[1] = WPS_PSK_LEN;
    643 	addr[2] = wpabuf_head(wps->dh_pubkey_e);
    644 	len[2] = wpabuf_len(wps->dh_pubkey_e);
    645 	addr[3] = wpabuf_head(wps->dh_pubkey_r);
    646 	len[3] = wpabuf_len(wps->dh_pubkey_r);
    647 	hmac_sha256_vector(wps->authkey, WPS_AUTHKEY_LEN, 4, addr, len, hash);
    648 
    649 	if (os_memcmp_const(wps->peer_hash1, hash, WPS_HASH_LEN) != 0) {
    650 		wpa_printf(MSG_DEBUG, "WPS: R-Hash1 derived from R-S1 does "
    651 			   "not match with the pre-committed value");
    652 		wps->config_error = WPS_CFG_DEV_PASSWORD_AUTH_FAILURE;
    653 		wps_pwd_auth_fail_event(wps->wps, 1, 1, wps->peer_dev.mac_addr);
    654 		return -1;
    655 	}
    656 
    657 	wpa_printf(MSG_DEBUG, "WPS: Registrar proved knowledge of the first "
    658 		   "half of the device password");
    659 
    660 	return 0;
    661 }
    662 
    663 
    664 static int wps_process_r_snonce2(struct wps_data *wps, const u8 *r_snonce2)
    665 {
    666 	u8 hash[SHA256_MAC_LEN];
    667 	const u8 *addr[4];
    668 	size_t len[4];
    669 
    670 	if (r_snonce2 == NULL) {
    671 		wpa_printf(MSG_DEBUG, "WPS: No R-SNonce2 received");
    672 		return -1;
    673 	}
    674 
    675 	wpa_hexdump_key(MSG_DEBUG, "WPS: R-SNonce2", r_snonce2,
    676 			WPS_SECRET_NONCE_LEN);
    677 
    678 	/* R-Hash2 = HMAC_AuthKey(R-S2 || PSK2 || PK_E || PK_R) */
    679 	addr[0] = r_snonce2;
    680 	len[0] = WPS_SECRET_NONCE_LEN;
    681 	addr[1] = wps->psk2;
    682 	len[1] = WPS_PSK_LEN;
    683 	addr[2] = wpabuf_head(wps->dh_pubkey_e);
    684 	len[2] = wpabuf_len(wps->dh_pubkey_e);
    685 	addr[3] = wpabuf_head(wps->dh_pubkey_r);
    686 	len[3] = wpabuf_len(wps->dh_pubkey_r);
    687 	hmac_sha256_vector(wps->authkey, WPS_AUTHKEY_LEN, 4, addr, len, hash);
    688 
    689 	if (os_memcmp_const(wps->peer_hash2, hash, WPS_HASH_LEN) != 0) {
    690 		wpa_printf(MSG_DEBUG, "WPS: R-Hash2 derived from R-S2 does "
    691 			   "not match with the pre-committed value");
    692 		wps->config_error = WPS_CFG_DEV_PASSWORD_AUTH_FAILURE;
    693 		wps_pwd_auth_fail_event(wps->wps, 1, 2, wps->peer_dev.mac_addr);
    694 		return -1;
    695 	}
    696 
    697 	wpa_printf(MSG_DEBUG, "WPS: Registrar proved knowledge of the second "
    698 		   "half of the device password");
    699 
    700 	return 0;
    701 }
    702 
    703 
    704 static int wps_process_cred_e(struct wps_data *wps, const u8 *cred,
    705 			      size_t cred_len, int wps2)
    706 {
    707 	struct wps_parse_attr attr;
    708 	struct wpabuf msg;
    709 	int ret = 0;
    710 
    711 	wpa_printf(MSG_DEBUG, "WPS: Received Credential");
    712 	os_memset(&wps->cred, 0, sizeof(wps->cred));
    713 	wpabuf_set(&msg, cred, cred_len);
    714 	if (wps_parse_msg(&msg, &attr) < 0 ||
    715 	    wps_process_cred(&attr, &wps->cred))
    716 		return -1;
    717 
    718 	if (os_memcmp(wps->cred.mac_addr, wps->wps->dev.mac_addr, ETH_ALEN) !=
    719 	    0) {
    720 		wpa_printf(MSG_DEBUG, "WPS: MAC Address in the Credential ("
    721 			   MACSTR ") does not match with own address (" MACSTR
    722 			   ")", MAC2STR(wps->cred.mac_addr),
    723 			   MAC2STR(wps->wps->dev.mac_addr));
    724 		/*
    725 		 * In theory, this could be consider fatal error, but there are
    726 		 * number of deployed implementations using other address here
    727 		 * due to unclarity in the specification. For interoperability
    728 		 * reasons, allow this to be processed since we do not really
    729 		 * use the MAC Address information for anything.
    730 		 */
    731 #ifdef CONFIG_WPS_STRICT
    732 		if (wps2) {
    733 			wpa_printf(MSG_INFO, "WPS: Do not accept incorrect "
    734 				   "MAC Address in AP Settings");
    735 			return -1;
    736 		}
    737 #endif /* CONFIG_WPS_STRICT */
    738 	}
    739 
    740 	if (!(wps->cred.encr_type &
    741 	      (WPS_ENCR_NONE | WPS_ENCR_TKIP | WPS_ENCR_AES))) {
    742 		if (wps->cred.encr_type & WPS_ENCR_WEP) {
    743 			wpa_printf(MSG_INFO, "WPS: Reject Credential "
    744 				   "due to WEP configuration");
    745 			wps->error_indication = WPS_EI_SECURITY_WEP_PROHIBITED;
    746 			return -2;
    747 		}
    748 
    749 		wpa_printf(MSG_INFO, "WPS: Reject Credential due to "
    750 			   "invalid encr_type 0x%x", wps->cred.encr_type);
    751 		return -1;
    752 	}
    753 
    754 	if (wps->wps->cred_cb) {
    755 		wps->cred.cred_attr = cred - 4;
    756 		wps->cred.cred_attr_len = cred_len + 4;
    757 		ret = wps->wps->cred_cb(wps->wps->cb_ctx, &wps->cred);
    758 		wps->cred.cred_attr = NULL;
    759 		wps->cred.cred_attr_len = 0;
    760 	}
    761 
    762 	return ret;
    763 }
    764 
    765 
    766 static int wps_process_creds(struct wps_data *wps, const u8 *cred[],
    767 			     u16 cred_len[], unsigned int num_cred, int wps2)
    768 {
    769 	size_t i;
    770 	int ok = 0;
    771 
    772 	if (wps->wps->ap)
    773 		return 0;
    774 
    775 	if (num_cred == 0) {
    776 		wpa_printf(MSG_DEBUG, "WPS: No Credential attributes "
    777 			   "received");
    778 		return -1;
    779 	}
    780 
    781 	for (i = 0; i < num_cred; i++) {
    782 		int res;
    783 		res = wps_process_cred_e(wps, cred[i], cred_len[i], wps2);
    784 		if (res == 0)
    785 			ok++;
    786 		else if (res == -2)
    787 			wpa_printf(MSG_DEBUG, "WPS: WEP credential skipped");
    788 		else
    789 			return -1;
    790 	}
    791 
    792 	if (ok == 0) {
    793 		wpa_printf(MSG_DEBUG, "WPS: No valid Credential attribute "
    794 			   "received");
    795 		return -1;
    796 	}
    797 
    798 	return 0;
    799 }
    800 
    801 
    802 static int wps_process_ap_settings_e(struct wps_data *wps,
    803 				     struct wps_parse_attr *attr,
    804 				     struct wpabuf *attrs, int wps2)
    805 {
    806 	struct wps_credential cred;
    807 	int ret = 0;
    808 
    809 	if (!wps->wps->ap)
    810 		return 0;
    811 
    812 	if (wps_process_ap_settings(attr, &cred) < 0)
    813 		return -1;
    814 
    815 	wpa_printf(MSG_INFO, "WPS: Received new AP configuration from "
    816 		   "Registrar");
    817 
    818 	if (os_memcmp(cred.mac_addr, wps->wps->dev.mac_addr, ETH_ALEN) !=
    819 	    0) {
    820 		wpa_printf(MSG_DEBUG, "WPS: MAC Address in the AP Settings ("
    821 			   MACSTR ") does not match with own address (" MACSTR
    822 			   ")", MAC2STR(cred.mac_addr),
    823 			   MAC2STR(wps->wps->dev.mac_addr));
    824 		/*
    825 		 * In theory, this could be consider fatal error, but there are
    826 		 * number of deployed implementations using other address here
    827 		 * due to unclarity in the specification. For interoperability
    828 		 * reasons, allow this to be processed since we do not really
    829 		 * use the MAC Address information for anything.
    830 		 */
    831 #ifdef CONFIG_WPS_STRICT
    832 		if (wps2) {
    833 			wpa_printf(MSG_INFO, "WPS: Do not accept incorrect "
    834 				   "MAC Address in AP Settings");
    835 			return -1;
    836 		}
    837 #endif /* CONFIG_WPS_STRICT */
    838 	}
    839 
    840 	if (!(cred.encr_type & (WPS_ENCR_NONE | WPS_ENCR_TKIP | WPS_ENCR_AES)))
    841 	{
    842 		if (cred.encr_type & WPS_ENCR_WEP) {
    843 			wpa_printf(MSG_INFO, "WPS: Reject new AP settings "
    844 				   "due to WEP configuration");
    845 			wps->error_indication = WPS_EI_SECURITY_WEP_PROHIBITED;
    846 			return -1;
    847 		}
    848 
    849 		wpa_printf(MSG_INFO, "WPS: Reject new AP settings due to "
    850 			   "invalid encr_type 0x%x", cred.encr_type);
    851 		return -1;
    852 	}
    853 
    854 #ifdef CONFIG_WPS_STRICT
    855 	if (wps2) {
    856 		if ((cred.encr_type & (WPS_ENCR_TKIP | WPS_ENCR_AES)) ==
    857 		    WPS_ENCR_TKIP ||
    858 		    (cred.auth_type & (WPS_AUTH_WPAPSK | WPS_AUTH_WPA2PSK)) ==
    859 		    WPS_AUTH_WPAPSK) {
    860 			wpa_printf(MSG_INFO, "WPS-STRICT: Invalid WSC 2.0 "
    861 				   "AP Settings: WPA-Personal/TKIP only");
    862 			wps->error_indication =
    863 				WPS_EI_SECURITY_TKIP_ONLY_PROHIBITED;
    864 			return -1;
    865 		}
    866 	}
    867 #endif /* CONFIG_WPS_STRICT */
    868 
    869 	if ((cred.encr_type & (WPS_ENCR_TKIP | WPS_ENCR_AES)) == WPS_ENCR_TKIP)
    870 	{
    871 		wpa_printf(MSG_DEBUG, "WPS: Upgrade encr_type TKIP -> "
    872 			   "TKIP+AES");
    873 		cred.encr_type |= WPS_ENCR_AES;
    874 	}
    875 
    876 	if ((cred.auth_type & (WPS_AUTH_WPAPSK | WPS_AUTH_WPA2PSK)) ==
    877 	    WPS_AUTH_WPAPSK) {
    878 		wpa_printf(MSG_DEBUG, "WPS: Upgrade auth_type WPAPSK -> "
    879 			   "WPAPSK+WPA2PSK");
    880 		cred.auth_type |= WPS_AUTH_WPA2PSK;
    881 	}
    882 
    883 	if (wps->wps->cred_cb) {
    884 		cred.cred_attr = wpabuf_head(attrs);
    885 		cred.cred_attr_len = wpabuf_len(attrs);
    886 		ret = wps->wps->cred_cb(wps->wps->cb_ctx, &cred);
    887 	}
    888 
    889 	return ret;
    890 }
    891 
    892 
    893 static int wps_process_dev_pw_id(struct wps_data *wps, const u8 *dev_pw_id)
    894 {
    895 	u16 id;
    896 
    897 	if (dev_pw_id == NULL) {
    898 		wpa_printf(MSG_DEBUG, "WPS: Device Password ID");
    899 		return -1;
    900 	}
    901 
    902 	id = WPA_GET_BE16(dev_pw_id);
    903 	if (wps->dev_pw_id == id) {
    904 		wpa_printf(MSG_DEBUG, "WPS: Device Password ID %u", id);
    905 		return 0;
    906 	}
    907 
    908 #ifdef CONFIG_P2P
    909 	if ((id == DEV_PW_DEFAULT &&
    910 	     wps->dev_pw_id == DEV_PW_REGISTRAR_SPECIFIED) ||
    911 	    (id == DEV_PW_REGISTRAR_SPECIFIED &&
    912 	     wps->dev_pw_id == DEV_PW_DEFAULT)) {
    913 		/*
    914 		 * Common P2P use cases indicate whether the PIN is from the
    915 		 * client or GO using Device Password Id in M1/M2 in a way that
    916 		 * does not look fully compliant with WSC specification. Anyway,
    917 		 * this is deployed and needs to be allowed, so ignore changes
    918 		 * between Registrar-Specified and Default PIN.
    919 		 */
    920 		wpa_printf(MSG_DEBUG, "WPS: Allow PIN Device Password ID "
    921 			   "change");
    922 		return 0;
    923 	}
    924 #endif /* CONFIG_P2P */
    925 
    926 	wpa_printf(MSG_DEBUG, "WPS: Registrar trying to change Device Password "
    927 		   "ID from %u to %u", wps->dev_pw_id, id);
    928 
    929 	if (wps->dev_pw_id == DEV_PW_PUSHBUTTON && id == DEV_PW_DEFAULT) {
    930 		wpa_printf(MSG_DEBUG,
    931 			   "WPS: Workaround - ignore PBC-to-PIN change");
    932 		return 0;
    933 	}
    934 
    935 	if (wps->alt_dev_password && wps->alt_dev_pw_id == id) {
    936 		wpa_printf(MSG_DEBUG, "WPS: Found a matching Device Password");
    937 		bin_clear_free(wps->dev_password, wps->dev_password_len);
    938 		wps->dev_pw_id = wps->alt_dev_pw_id;
    939 		wps->dev_password = wps->alt_dev_password;
    940 		wps->dev_password_len = wps->alt_dev_password_len;
    941 		wps->alt_dev_password = NULL;
    942 		wps->alt_dev_password_len = 0;
    943 		return 0;
    944 	}
    945 
    946 	return -1;
    947 }
    948 
    949 
    950 static enum wps_process_res wps_process_m2(struct wps_data *wps,
    951 					   const struct wpabuf *msg,
    952 					   struct wps_parse_attr *attr)
    953 {
    954 	wpa_printf(MSG_DEBUG, "WPS: Received M2");
    955 
    956 	if (wps->state != RECV_M2) {
    957 		wpa_printf(MSG_DEBUG, "WPS: Unexpected state (%d) for "
    958 			   "receiving M2", wps->state);
    959 		wps->state = SEND_WSC_NACK;
    960 		return WPS_CONTINUE;
    961 	}
    962 
    963 	if (wps_process_registrar_nonce(wps, attr->registrar_nonce) ||
    964 	    wps_process_enrollee_nonce(wps, attr->enrollee_nonce) ||
    965 	    wps_process_uuid_r(wps, attr->uuid_r) ||
    966 	    wps_process_dev_pw_id(wps, attr->dev_password_id)) {
    967 		wps->state = SEND_WSC_NACK;
    968 		return WPS_CONTINUE;
    969 	}
    970 
    971 	/*
    972 	 * Stop here on an AP as an Enrollee if AP Setup is locked unless the
    973 	 * special locked mode is used to allow protocol run up to M7 in order
    974 	 * to support external Registrars that only learn the current AP
    975 	 * configuration without changing it.
    976 	 */
    977 	if (wps->wps->ap &&
    978 	    ((wps->wps->ap_setup_locked && wps->wps->ap_setup_locked != 2) ||
    979 	     wps->dev_password == NULL)) {
    980 		wpa_printf(MSG_DEBUG, "WPS: AP Setup is locked - refuse "
    981 			   "registration of a new Registrar");
    982 		wps->config_error = WPS_CFG_SETUP_LOCKED;
    983 		wps->state = SEND_WSC_NACK;
    984 		return WPS_CONTINUE;
    985 	}
    986 
    987 	if (wps_process_pubkey(wps, attr->public_key, attr->public_key_len) ||
    988 	    wps_process_authenticator(wps, attr->authenticator, msg) ||
    989 	    wps_process_device_attrs(&wps->peer_dev, attr)) {
    990 		wps->state = SEND_WSC_NACK;
    991 		return WPS_CONTINUE;
    992 	}
    993 
    994 #ifdef CONFIG_WPS_NFC
    995 	if (wps->peer_pubkey_hash_set) {
    996 		struct wpabuf *decrypted;
    997 		struct wps_parse_attr eattr;
    998 
    999 		decrypted = wps_decrypt_encr_settings(wps, attr->encr_settings,
   1000 						      attr->encr_settings_len);
   1001 		if (decrypted == NULL) {
   1002 			wpa_printf(MSG_DEBUG, "WPS: Failed to decrypt "
   1003 				   "Encrypted Settings attribute");
   1004 			wps->state = SEND_WSC_NACK;
   1005 			return WPS_CONTINUE;
   1006 		}
   1007 
   1008 		wpa_printf(MSG_DEBUG, "WPS: Processing decrypted Encrypted "
   1009 			   "Settings attribute");
   1010 		if (wps_parse_msg(decrypted, &eattr) < 0 ||
   1011 		    wps_process_key_wrap_auth(wps, decrypted,
   1012 					      eattr.key_wrap_auth) ||
   1013 		    wps_process_creds(wps, eattr.cred, eattr.cred_len,
   1014 				      eattr.num_cred, attr->version2 != NULL)) {
   1015 			wpabuf_clear_free(decrypted);
   1016 			wps->state = SEND_WSC_NACK;
   1017 			return WPS_CONTINUE;
   1018 		}
   1019 		wpabuf_clear_free(decrypted);
   1020 
   1021 		wps->state = WPS_MSG_DONE;
   1022 		return WPS_CONTINUE;
   1023 	}
   1024 #endif /* CONFIG_WPS_NFC */
   1025 
   1026 	wps->state = SEND_M3;
   1027 	return WPS_CONTINUE;
   1028 }
   1029 
   1030 
   1031 static enum wps_process_res wps_process_m2d(struct wps_data *wps,
   1032 					    struct wps_parse_attr *attr)
   1033 {
   1034 	wpa_printf(MSG_DEBUG, "WPS: Received M2D");
   1035 
   1036 	if (wps->state != RECV_M2) {
   1037 		wpa_printf(MSG_DEBUG, "WPS: Unexpected state (%d) for "
   1038 			   "receiving M2D", wps->state);
   1039 		wps->state = SEND_WSC_NACK;
   1040 		return WPS_CONTINUE;
   1041 	}
   1042 
   1043 	wpa_hexdump_ascii(MSG_DEBUG, "WPS: Manufacturer",
   1044 			  attr->manufacturer, attr->manufacturer_len);
   1045 	wpa_hexdump_ascii(MSG_DEBUG, "WPS: Model Name",
   1046 			  attr->model_name, attr->model_name_len);
   1047 	wpa_hexdump_ascii(MSG_DEBUG, "WPS: Model Number",
   1048 			  attr->model_number, attr->model_number_len);
   1049 	wpa_hexdump_ascii(MSG_DEBUG, "WPS: Serial Number",
   1050 			  attr->serial_number, attr->serial_number_len);
   1051 	wpa_hexdump_ascii(MSG_DEBUG, "WPS: Device Name",
   1052 			  attr->dev_name, attr->dev_name_len);
   1053 
   1054 	if (wps->wps->event_cb) {
   1055 		union wps_event_data data;
   1056 		struct wps_event_m2d *m2d = &data.m2d;
   1057 		os_memset(&data, 0, sizeof(data));
   1058 		if (attr->config_methods)
   1059 			m2d->config_methods =
   1060 				WPA_GET_BE16(attr->config_methods);
   1061 		m2d->manufacturer = attr->manufacturer;
   1062 		m2d->manufacturer_len = attr->manufacturer_len;
   1063 		m2d->model_name = attr->model_name;
   1064 		m2d->model_name_len = attr->model_name_len;
   1065 		m2d->model_number = attr->model_number;
   1066 		m2d->model_number_len = attr->model_number_len;
   1067 		m2d->serial_number = attr->serial_number;
   1068 		m2d->serial_number_len = attr->serial_number_len;
   1069 		m2d->dev_name = attr->dev_name;
   1070 		m2d->dev_name_len = attr->dev_name_len;
   1071 		m2d->primary_dev_type = attr->primary_dev_type;
   1072 		if (attr->config_error)
   1073 			m2d->config_error =
   1074 				WPA_GET_BE16(attr->config_error);
   1075 		if (attr->dev_password_id)
   1076 			m2d->dev_password_id =
   1077 				WPA_GET_BE16(attr->dev_password_id);
   1078 		wps->wps->event_cb(wps->wps->cb_ctx, WPS_EV_M2D, &data);
   1079 	}
   1080 
   1081 	wps->state = RECEIVED_M2D;
   1082 	return WPS_CONTINUE;
   1083 }
   1084 
   1085 
   1086 static enum wps_process_res wps_process_m4(struct wps_data *wps,
   1087 					   const struct wpabuf *msg,
   1088 					   struct wps_parse_attr *attr)
   1089 {
   1090 	struct wpabuf *decrypted;
   1091 	struct wps_parse_attr eattr;
   1092 
   1093 	wpa_printf(MSG_DEBUG, "WPS: Received M4");
   1094 
   1095 	if (wps->state != RECV_M4) {
   1096 		wpa_printf(MSG_DEBUG, "WPS: Unexpected state (%d) for "
   1097 			   "receiving M4", wps->state);
   1098 		wps->state = SEND_WSC_NACK;
   1099 		return WPS_CONTINUE;
   1100 	}
   1101 
   1102 	if (wps_process_enrollee_nonce(wps, attr->enrollee_nonce) ||
   1103 	    wps_process_authenticator(wps, attr->authenticator, msg) ||
   1104 	    wps_process_r_hash1(wps, attr->r_hash1) ||
   1105 	    wps_process_r_hash2(wps, attr->r_hash2)) {
   1106 		wps->state = SEND_WSC_NACK;
   1107 		return WPS_CONTINUE;
   1108 	}
   1109 
   1110 	decrypted = wps_decrypt_encr_settings(wps, attr->encr_settings,
   1111 					      attr->encr_settings_len);
   1112 	if (decrypted == NULL) {
   1113 		wpa_printf(MSG_DEBUG, "WPS: Failed to decrypted Encrypted "
   1114 			   "Settings attribute");
   1115 		wps->state = SEND_WSC_NACK;
   1116 		return WPS_CONTINUE;
   1117 	}
   1118 
   1119 	if (wps_validate_m4_encr(decrypted, attr->version2 != NULL) < 0) {
   1120 		wpabuf_clear_free(decrypted);
   1121 		wps->state = SEND_WSC_NACK;
   1122 		return WPS_CONTINUE;
   1123 	}
   1124 
   1125 	wpa_printf(MSG_DEBUG, "WPS: Processing decrypted Encrypted Settings "
   1126 		   "attribute");
   1127 	if (wps_parse_msg(decrypted, &eattr) < 0 ||
   1128 	    wps_process_key_wrap_auth(wps, decrypted, eattr.key_wrap_auth) ||
   1129 	    wps_process_r_snonce1(wps, eattr.r_snonce1)) {
   1130 		wpabuf_clear_free(decrypted);
   1131 		wps->state = SEND_WSC_NACK;
   1132 		return WPS_CONTINUE;
   1133 	}
   1134 	wpabuf_clear_free(decrypted);
   1135 
   1136 	wps->state = SEND_M5;
   1137 	return WPS_CONTINUE;
   1138 }
   1139 
   1140 
   1141 static enum wps_process_res wps_process_m6(struct wps_data *wps,
   1142 					   const struct wpabuf *msg,
   1143 					   struct wps_parse_attr *attr)
   1144 {
   1145 	struct wpabuf *decrypted;
   1146 	struct wps_parse_attr eattr;
   1147 
   1148 	wpa_printf(MSG_DEBUG, "WPS: Received M6");
   1149 
   1150 	if (wps->state != RECV_M6) {
   1151 		wpa_printf(MSG_DEBUG, "WPS: Unexpected state (%d) for "
   1152 			   "receiving M6", wps->state);
   1153 		wps->state = SEND_WSC_NACK;
   1154 		return WPS_CONTINUE;
   1155 	}
   1156 
   1157 	if (wps_process_enrollee_nonce(wps, attr->enrollee_nonce) ||
   1158 	    wps_process_authenticator(wps, attr->authenticator, msg)) {
   1159 		wps->state = SEND_WSC_NACK;
   1160 		return WPS_CONTINUE;
   1161 	}
   1162 
   1163 	decrypted = wps_decrypt_encr_settings(wps, attr->encr_settings,
   1164 					      attr->encr_settings_len);
   1165 	if (decrypted == NULL) {
   1166 		wpa_printf(MSG_DEBUG, "WPS: Failed to decrypted Encrypted "
   1167 			   "Settings attribute");
   1168 		wps->state = SEND_WSC_NACK;
   1169 		return WPS_CONTINUE;
   1170 	}
   1171 
   1172 	if (wps_validate_m6_encr(decrypted, attr->version2 != NULL) < 0) {
   1173 		wpabuf_clear_free(decrypted);
   1174 		wps->state = SEND_WSC_NACK;
   1175 		return WPS_CONTINUE;
   1176 	}
   1177 
   1178 	wpa_printf(MSG_DEBUG, "WPS: Processing decrypted Encrypted Settings "
   1179 		   "attribute");
   1180 	if (wps_parse_msg(decrypted, &eattr) < 0 ||
   1181 	    wps_process_key_wrap_auth(wps, decrypted, eattr.key_wrap_auth) ||
   1182 	    wps_process_r_snonce2(wps, eattr.r_snonce2)) {
   1183 		wpabuf_clear_free(decrypted);
   1184 		wps->state = SEND_WSC_NACK;
   1185 		return WPS_CONTINUE;
   1186 	}
   1187 	wpabuf_clear_free(decrypted);
   1188 
   1189 	if (wps->wps->ap)
   1190 		wps->wps->event_cb(wps->wps->cb_ctx, WPS_EV_AP_PIN_SUCCESS,
   1191 				   NULL);
   1192 
   1193 	wps->state = SEND_M7;
   1194 	return WPS_CONTINUE;
   1195 }
   1196 
   1197 
   1198 static enum wps_process_res wps_process_m8(struct wps_data *wps,
   1199 					   const struct wpabuf *msg,
   1200 					   struct wps_parse_attr *attr)
   1201 {
   1202 	struct wpabuf *decrypted;
   1203 	struct wps_parse_attr eattr;
   1204 
   1205 	wpa_printf(MSG_DEBUG, "WPS: Received M8");
   1206 
   1207 	if (wps->state != RECV_M8) {
   1208 		wpa_printf(MSG_DEBUG, "WPS: Unexpected state (%d) for "
   1209 			   "receiving M8", wps->state);
   1210 		wps->state = SEND_WSC_NACK;
   1211 		return WPS_CONTINUE;
   1212 	}
   1213 
   1214 	if (wps_process_enrollee_nonce(wps, attr->enrollee_nonce) ||
   1215 	    wps_process_authenticator(wps, attr->authenticator, msg)) {
   1216 		wps->state = SEND_WSC_NACK;
   1217 		return WPS_CONTINUE;
   1218 	}
   1219 
   1220 	if (wps->wps->ap && wps->wps->ap_setup_locked) {
   1221 		/*
   1222 		 * Stop here if special ap_setup_locked == 2 mode allowed the
   1223 		 * protocol to continue beyond M2. This allows ER to learn the
   1224 		 * current AP settings without changing them.
   1225 		 */
   1226 		wpa_printf(MSG_DEBUG, "WPS: AP Setup is locked - refuse "
   1227 			   "registration of a new Registrar");
   1228 		wps->config_error = WPS_CFG_SETUP_LOCKED;
   1229 		wps->state = SEND_WSC_NACK;
   1230 		return WPS_CONTINUE;
   1231 	}
   1232 
   1233 	decrypted = wps_decrypt_encr_settings(wps, attr->encr_settings,
   1234 					      attr->encr_settings_len);
   1235 	if (decrypted == NULL) {
   1236 		wpa_printf(MSG_DEBUG, "WPS: Failed to decrypted Encrypted "
   1237 			   "Settings attribute");
   1238 		wps->state = SEND_WSC_NACK;
   1239 		return WPS_CONTINUE;
   1240 	}
   1241 
   1242 	if (wps_validate_m8_encr(decrypted, wps->wps->ap,
   1243 				 attr->version2 != NULL) < 0) {
   1244 		wpabuf_clear_free(decrypted);
   1245 		wps->state = SEND_WSC_NACK;
   1246 		return WPS_CONTINUE;
   1247 	}
   1248 
   1249 	wpa_printf(MSG_DEBUG, "WPS: Processing decrypted Encrypted Settings "
   1250 		   "attribute");
   1251 	if (wps_parse_msg(decrypted, &eattr) < 0 ||
   1252 	    wps_process_key_wrap_auth(wps, decrypted, eattr.key_wrap_auth) ||
   1253 	    wps_process_creds(wps, eattr.cred, eattr.cred_len,
   1254 			      eattr.num_cred, attr->version2 != NULL) ||
   1255 	    wps_process_ap_settings_e(wps, &eattr, decrypted,
   1256 				      attr->version2 != NULL)) {
   1257 		wpabuf_clear_free(decrypted);
   1258 		wps->state = SEND_WSC_NACK;
   1259 		return WPS_CONTINUE;
   1260 	}
   1261 	wpabuf_clear_free(decrypted);
   1262 
   1263 	wps->state = WPS_MSG_DONE;
   1264 	return WPS_CONTINUE;
   1265 }
   1266 
   1267 
   1268 static enum wps_process_res wps_process_wsc_msg(struct wps_data *wps,
   1269 						const struct wpabuf *msg)
   1270 {
   1271 	struct wps_parse_attr attr;
   1272 	enum wps_process_res ret = WPS_CONTINUE;
   1273 
   1274 	wpa_printf(MSG_DEBUG, "WPS: Received WSC_MSG");
   1275 
   1276 	if (wps_parse_msg(msg, &attr) < 0)
   1277 		return WPS_FAILURE;
   1278 
   1279 	if (attr.enrollee_nonce == NULL ||
   1280 	    os_memcmp(wps->nonce_e, attr.enrollee_nonce, WPS_NONCE_LEN) != 0) {
   1281 		wpa_printf(MSG_DEBUG, "WPS: Mismatch in enrollee nonce");
   1282 		return WPS_FAILURE;
   1283 	}
   1284 
   1285 	if (attr.msg_type == NULL) {
   1286 		wpa_printf(MSG_DEBUG, "WPS: No Message Type attribute");
   1287 		wps->state = SEND_WSC_NACK;
   1288 		return WPS_CONTINUE;
   1289 	}
   1290 
   1291 	switch (*attr.msg_type) {
   1292 	case WPS_M2:
   1293 		if (wps_validate_m2(msg) < 0)
   1294 			return WPS_FAILURE;
   1295 		ret = wps_process_m2(wps, msg, &attr);
   1296 		break;
   1297 	case WPS_M2D:
   1298 		if (wps_validate_m2d(msg) < 0)
   1299 			return WPS_FAILURE;
   1300 		ret = wps_process_m2d(wps, &attr);
   1301 		break;
   1302 	case WPS_M4:
   1303 		if (wps_validate_m4(msg) < 0)
   1304 			return WPS_FAILURE;
   1305 		ret = wps_process_m4(wps, msg, &attr);
   1306 		if (ret == WPS_FAILURE || wps->state == SEND_WSC_NACK)
   1307 			wps_fail_event(wps->wps, WPS_M4, wps->config_error,
   1308 				       wps->error_indication,
   1309 				       wps->peer_dev.mac_addr);
   1310 		break;
   1311 	case WPS_M6:
   1312 		if (wps_validate_m6(msg) < 0)
   1313 			return WPS_FAILURE;
   1314 		ret = wps_process_m6(wps, msg, &attr);
   1315 		if (ret == WPS_FAILURE || wps->state == SEND_WSC_NACK)
   1316 			wps_fail_event(wps->wps, WPS_M6, wps->config_error,
   1317 				       wps->error_indication,
   1318 				       wps->peer_dev.mac_addr);
   1319 		break;
   1320 	case WPS_M8:
   1321 		if (wps_validate_m8(msg) < 0)
   1322 			return WPS_FAILURE;
   1323 		ret = wps_process_m8(wps, msg, &attr);
   1324 		if (ret == WPS_FAILURE || wps->state == SEND_WSC_NACK)
   1325 			wps_fail_event(wps->wps, WPS_M8, wps->config_error,
   1326 				       wps->error_indication,
   1327 				       wps->peer_dev.mac_addr);
   1328 		break;
   1329 	default:
   1330 		wpa_printf(MSG_DEBUG, "WPS: Unsupported Message Type %d",
   1331 			   *attr.msg_type);
   1332 		return WPS_FAILURE;
   1333 	}
   1334 
   1335 	/*
   1336 	 * Save a copy of the last message for Authenticator derivation if we
   1337 	 * are continuing. However, skip M2D since it is not authenticated and
   1338 	 * neither is the ACK/NACK response frame. This allows the possibly
   1339 	 * following M2 to be processed correctly by using the previously sent
   1340 	 * M1 in Authenticator derivation.
   1341 	 */
   1342 	if (ret == WPS_CONTINUE && *attr.msg_type != WPS_M2D) {
   1343 		/* Save a copy of the last message for Authenticator derivation
   1344 		 */
   1345 		wpabuf_free(wps->last_msg);
   1346 		wps->last_msg = wpabuf_dup(msg);
   1347 	}
   1348 
   1349 	return ret;
   1350 }
   1351 
   1352 
   1353 static enum wps_process_res wps_process_wsc_ack(struct wps_data *wps,
   1354 						const struct wpabuf *msg)
   1355 {
   1356 	struct wps_parse_attr attr;
   1357 
   1358 	wpa_printf(MSG_DEBUG, "WPS: Received WSC_ACK");
   1359 
   1360 	if (wps_parse_msg(msg, &attr) < 0)
   1361 		return WPS_FAILURE;
   1362 
   1363 	if (attr.msg_type == NULL) {
   1364 		wpa_printf(MSG_DEBUG, "WPS: No Message Type attribute");
   1365 		return WPS_FAILURE;
   1366 	}
   1367 
   1368 	if (*attr.msg_type != WPS_WSC_ACK) {
   1369 		wpa_printf(MSG_DEBUG, "WPS: Invalid Message Type %d",
   1370 			   *attr.msg_type);
   1371 		return WPS_FAILURE;
   1372 	}
   1373 
   1374 	if (attr.registrar_nonce == NULL ||
   1375 	    os_memcmp(wps->nonce_r, attr.registrar_nonce, WPS_NONCE_LEN) != 0)
   1376 	{
   1377 		wpa_printf(MSG_DEBUG, "WPS: Mismatch in registrar nonce");
   1378 		return WPS_FAILURE;
   1379 	}
   1380 
   1381 	if (attr.enrollee_nonce == NULL ||
   1382 	    os_memcmp(wps->nonce_e, attr.enrollee_nonce, WPS_NONCE_LEN) != 0) {
   1383 		wpa_printf(MSG_DEBUG, "WPS: Mismatch in enrollee nonce");
   1384 		return WPS_FAILURE;
   1385 	}
   1386 
   1387 	if (wps->state == RECV_ACK && wps->wps->ap) {
   1388 		wpa_printf(MSG_DEBUG, "WPS: External Registrar registration "
   1389 			   "completed successfully");
   1390 		wps_success_event(wps->wps, wps->peer_dev.mac_addr);
   1391 		wps->state = WPS_FINISHED;
   1392 		return WPS_DONE;
   1393 	}
   1394 
   1395 	return WPS_FAILURE;
   1396 }
   1397 
   1398 
   1399 static enum wps_process_res wps_process_wsc_nack(struct wps_data *wps,
   1400 						 const struct wpabuf *msg)
   1401 {
   1402 	struct wps_parse_attr attr;
   1403 	u16 config_error;
   1404 
   1405 	wpa_printf(MSG_DEBUG, "WPS: Received WSC_NACK");
   1406 
   1407 	if (wps_parse_msg(msg, &attr) < 0)
   1408 		return WPS_FAILURE;
   1409 
   1410 	if (attr.msg_type == NULL) {
   1411 		wpa_printf(MSG_DEBUG, "WPS: No Message Type attribute");
   1412 		return WPS_FAILURE;
   1413 	}
   1414 
   1415 	if (*attr.msg_type != WPS_WSC_NACK) {
   1416 		wpa_printf(MSG_DEBUG, "WPS: Invalid Message Type %d",
   1417 			   *attr.msg_type);
   1418 		return WPS_FAILURE;
   1419 	}
   1420 
   1421 	if (attr.registrar_nonce == NULL ||
   1422 	    os_memcmp(wps->nonce_r, attr.registrar_nonce, WPS_NONCE_LEN) != 0)
   1423 	{
   1424 		wpa_printf(MSG_DEBUG, "WPS: Mismatch in registrar nonce");
   1425 		wpa_hexdump(MSG_DEBUG, "WPS: Received Registrar Nonce",
   1426 			    attr.registrar_nonce, WPS_NONCE_LEN);
   1427 		wpa_hexdump(MSG_DEBUG, "WPS: Expected Registrar Nonce",
   1428 			    wps->nonce_r, WPS_NONCE_LEN);
   1429 		return WPS_FAILURE;
   1430 	}
   1431 
   1432 	if (attr.enrollee_nonce == NULL ||
   1433 	    os_memcmp(wps->nonce_e, attr.enrollee_nonce, WPS_NONCE_LEN) != 0) {
   1434 		wpa_printf(MSG_DEBUG, "WPS: Mismatch in enrollee nonce");
   1435 		wpa_hexdump(MSG_DEBUG, "WPS: Received Enrollee Nonce",
   1436 			    attr.enrollee_nonce, WPS_NONCE_LEN);
   1437 		wpa_hexdump(MSG_DEBUG, "WPS: Expected Enrollee Nonce",
   1438 			    wps->nonce_e, WPS_NONCE_LEN);
   1439 		return WPS_FAILURE;
   1440 	}
   1441 
   1442 	if (attr.config_error == NULL) {
   1443 		wpa_printf(MSG_DEBUG, "WPS: No Configuration Error attribute "
   1444 			   "in WSC_NACK");
   1445 		return WPS_FAILURE;
   1446 	}
   1447 
   1448 	config_error = WPA_GET_BE16(attr.config_error);
   1449 	wpa_printf(MSG_DEBUG, "WPS: Registrar terminated negotiation with "
   1450 		   "Configuration Error %d", config_error);
   1451 
   1452 	switch (wps->state) {
   1453 	case RECV_M4:
   1454 		wps_fail_event(wps->wps, WPS_M3, config_error,
   1455 			       wps->error_indication, wps->peer_dev.mac_addr);
   1456 		break;
   1457 	case RECV_M6:
   1458 		wps_fail_event(wps->wps, WPS_M5, config_error,
   1459 			       wps->error_indication, wps->peer_dev.mac_addr);
   1460 		break;
   1461 	case RECV_M8:
   1462 		wps_fail_event(wps->wps, WPS_M7, config_error,
   1463 			       wps->error_indication, wps->peer_dev.mac_addr);
   1464 		break;
   1465 	default:
   1466 		break;
   1467 	}
   1468 
   1469 	/* Followed by NACK if Enrollee is Supplicant or EAP-Failure if
   1470 	 * Enrollee is Authenticator */
   1471 	wps->state = SEND_WSC_NACK;
   1472 
   1473 	return WPS_FAILURE;
   1474 }
   1475 
   1476 
   1477 enum wps_process_res wps_enrollee_process_msg(struct wps_data *wps,
   1478 					      enum wsc_op_code op_code,
   1479 					      const struct wpabuf *msg)
   1480 {
   1481 
   1482 	wpa_printf(MSG_DEBUG, "WPS: Processing received message (len=%lu "
   1483 		   "op_code=%d)",
   1484 		   (unsigned long) wpabuf_len(msg), op_code);
   1485 
   1486 	if (op_code == WSC_UPnP) {
   1487 		/* Determine the OpCode based on message type attribute */
   1488 		struct wps_parse_attr attr;
   1489 		if (wps_parse_msg(msg, &attr) == 0 && attr.msg_type) {
   1490 			if (*attr.msg_type == WPS_WSC_ACK)
   1491 				op_code = WSC_ACK;
   1492 			else if (*attr.msg_type == WPS_WSC_NACK)
   1493 				op_code = WSC_NACK;
   1494 		}
   1495 	}
   1496 
   1497 	switch (op_code) {
   1498 	case WSC_MSG:
   1499 	case WSC_UPnP:
   1500 		return wps_process_wsc_msg(wps, msg);
   1501 	case WSC_ACK:
   1502 		if (wps_validate_wsc_ack(msg) < 0)
   1503 			return WPS_FAILURE;
   1504 		return wps_process_wsc_ack(wps, msg);
   1505 	case WSC_NACK:
   1506 		if (wps_validate_wsc_nack(msg) < 0)
   1507 			return WPS_FAILURE;
   1508 		return wps_process_wsc_nack(wps, msg);
   1509 	default:
   1510 		wpa_printf(MSG_DEBUG, "WPS: Unsupported op_code %d", op_code);
   1511 		return WPS_FAILURE;
   1512 	}
   1513 }
   1514