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