wps_common.c revision 1f69aa52ea2e0a73ac502565df8c666ee49cab6a
1/*
2 * Wi-Fi Protected Setup - common functionality
3 * Copyright (c) 2008-2009, Jouni Malinen <j@w1.fi>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 *
9 * Alternatively, this software may be distributed under the terms of BSD
10 * license.
11 *
12 * See README and COPYING for more details.
13 */
14
15#include "includes.h"
16
17#include "common.h"
18#include "crypto/aes_wrap.h"
19#include "crypto/crypto.h"
20#include "crypto/dh_group5.h"
21#include "crypto/sha1.h"
22#include "crypto/sha256.h"
23#include "crypto/random.h"
24#include "wps_i.h"
25
26
27void wps_kdf(const u8 *key, const u8 *label_prefix, size_t label_prefix_len,
28	     const char *label, u8 *res, size_t res_len)
29{
30	u8 i_buf[4], key_bits[4];
31	const u8 *addr[4];
32	size_t len[4];
33	int i, iter;
34	u8 hash[SHA256_MAC_LEN], *opos;
35	size_t left;
36
37	WPA_PUT_BE32(key_bits, res_len * 8);
38
39	addr[0] = i_buf;
40	len[0] = sizeof(i_buf);
41	addr[1] = label_prefix;
42	len[1] = label_prefix_len;
43	addr[2] = (const u8 *) label;
44	len[2] = os_strlen(label);
45	addr[3] = key_bits;
46	len[3] = sizeof(key_bits);
47
48	iter = (res_len + SHA256_MAC_LEN - 1) / SHA256_MAC_LEN;
49	opos = res;
50	left = res_len;
51
52	for (i = 1; i <= iter; i++) {
53		WPA_PUT_BE32(i_buf, i);
54		hmac_sha256_vector(key, SHA256_MAC_LEN, 4, addr, len, hash);
55		if (i < iter) {
56			os_memcpy(opos, hash, SHA256_MAC_LEN);
57			opos += SHA256_MAC_LEN;
58			left -= SHA256_MAC_LEN;
59		} else
60			os_memcpy(opos, hash, left);
61	}
62}
63
64
65int wps_derive_keys(struct wps_data *wps)
66{
67	struct wpabuf *pubkey, *dh_shared;
68	u8 dhkey[SHA256_MAC_LEN], kdk[SHA256_MAC_LEN];
69	const u8 *addr[3];
70	size_t len[3];
71	u8 keys[WPS_AUTHKEY_LEN + WPS_KEYWRAPKEY_LEN + WPS_EMSK_LEN];
72
73	if (wps->dh_privkey == NULL) {
74		wpa_printf(MSG_DEBUG, "WPS: Own DH private key not available");
75		return -1;
76	}
77
78	pubkey = wps->registrar ? wps->dh_pubkey_e : wps->dh_pubkey_r;
79	if (pubkey == NULL) {
80		wpa_printf(MSG_DEBUG, "WPS: Peer DH public key not available");
81		return -1;
82	}
83
84	wpa_hexdump_buf_key(MSG_DEBUG, "WPS: DH Private Key", wps->dh_privkey);
85	wpa_hexdump_buf(MSG_DEBUG, "WPS: DH peer Public Key", pubkey);
86	dh_shared = dh5_derive_shared(wps->dh_ctx, pubkey, wps->dh_privkey);
87	dh5_free(wps->dh_ctx);
88	wps->dh_ctx = NULL;
89	dh_shared = wpabuf_zeropad(dh_shared, 192);
90	if (dh_shared == NULL) {
91		wpa_printf(MSG_DEBUG, "WPS: Failed to derive DH shared key");
92		return -1;
93	}
94
95	/* Own DH private key is not needed anymore */
96	wpabuf_free(wps->dh_privkey);
97	wps->dh_privkey = NULL;
98
99	wpa_hexdump_buf_key(MSG_DEBUG, "WPS: DH shared key", dh_shared);
100
101	/* DHKey = SHA-256(g^AB mod p) */
102	addr[0] = wpabuf_head(dh_shared);
103	len[0] = wpabuf_len(dh_shared);
104	sha256_vector(1, addr, len, dhkey);
105	wpa_hexdump_key(MSG_DEBUG, "WPS: DHKey", dhkey, sizeof(dhkey));
106	wpabuf_free(dh_shared);
107
108	/* KDK = HMAC-SHA-256_DHKey(N1 || EnrolleeMAC || N2) */
109	addr[0] = wps->nonce_e;
110	len[0] = WPS_NONCE_LEN;
111	addr[1] = wps->mac_addr_e;
112	len[1] = ETH_ALEN;
113	addr[2] = wps->nonce_r;
114	len[2] = WPS_NONCE_LEN;
115	hmac_sha256_vector(dhkey, sizeof(dhkey), 3, addr, len, kdk);
116	wpa_hexdump_key(MSG_DEBUG, "WPS: KDK", kdk, sizeof(kdk));
117
118	wps_kdf(kdk, NULL, 0, "Wi-Fi Easy and Secure Key Derivation",
119		keys, sizeof(keys));
120	os_memcpy(wps->authkey, keys, WPS_AUTHKEY_LEN);
121	os_memcpy(wps->keywrapkey, keys + WPS_AUTHKEY_LEN, WPS_KEYWRAPKEY_LEN);
122	os_memcpy(wps->emsk, keys + WPS_AUTHKEY_LEN + WPS_KEYWRAPKEY_LEN,
123		  WPS_EMSK_LEN);
124
125	wpa_hexdump_key(MSG_DEBUG, "WPS: AuthKey",
126			wps->authkey, WPS_AUTHKEY_LEN);
127	wpa_hexdump_key(MSG_DEBUG, "WPS: KeyWrapKey",
128			wps->keywrapkey, WPS_KEYWRAPKEY_LEN);
129	wpa_hexdump_key(MSG_DEBUG, "WPS: EMSK", wps->emsk, WPS_EMSK_LEN);
130
131	return 0;
132}
133
134
135void wps_derive_psk(struct wps_data *wps, const u8 *dev_passwd,
136		    size_t dev_passwd_len)
137{
138	u8 hash[SHA256_MAC_LEN];
139
140	hmac_sha256(wps->authkey, WPS_AUTHKEY_LEN, dev_passwd,
141		    (dev_passwd_len + 1) / 2, hash);
142	os_memcpy(wps->psk1, hash, WPS_PSK_LEN);
143	hmac_sha256(wps->authkey, WPS_AUTHKEY_LEN,
144		    dev_passwd + (dev_passwd_len + 1) / 2,
145		    dev_passwd_len / 2, hash);
146	os_memcpy(wps->psk2, hash, WPS_PSK_LEN);
147
148	wpa_hexdump_ascii_key(MSG_DEBUG, "WPS: Device Password",
149			      dev_passwd, dev_passwd_len);
150	wpa_hexdump_key(MSG_DEBUG, "WPS: PSK1", wps->psk1, WPS_PSK_LEN);
151	wpa_hexdump_key(MSG_DEBUG, "WPS: PSK2", wps->psk2, WPS_PSK_LEN);
152}
153
154
155struct wpabuf * wps_decrypt_encr_settings(struct wps_data *wps, const u8 *encr,
156					  size_t encr_len)
157{
158	struct wpabuf *decrypted;
159	const size_t block_size = 16;
160	size_t i;
161	u8 pad;
162	const u8 *pos;
163
164	/* AES-128-CBC */
165	if (encr == NULL || encr_len < 2 * block_size || encr_len % block_size)
166	{
167		wpa_printf(MSG_DEBUG, "WPS: No Encrypted Settings received");
168		return NULL;
169	}
170
171	decrypted = wpabuf_alloc(encr_len - block_size);
172	if (decrypted == NULL)
173		return NULL;
174
175	wpa_hexdump(MSG_MSGDUMP, "WPS: Encrypted Settings", encr, encr_len);
176	wpabuf_put_data(decrypted, encr + block_size, encr_len - block_size);
177	if (aes_128_cbc_decrypt(wps->keywrapkey, encr, wpabuf_mhead(decrypted),
178				wpabuf_len(decrypted))) {
179		wpabuf_free(decrypted);
180		return NULL;
181	}
182
183	wpa_hexdump_buf_key(MSG_MSGDUMP, "WPS: Decrypted Encrypted Settings",
184			    decrypted);
185
186	pos = wpabuf_head_u8(decrypted) + wpabuf_len(decrypted) - 1;
187	pad = *pos;
188	if (pad > wpabuf_len(decrypted)) {
189		wpa_printf(MSG_DEBUG, "WPS: Invalid PKCS#5 v2.0 pad value");
190		wpabuf_free(decrypted);
191		return NULL;
192	}
193	for (i = 0; i < pad; i++) {
194		if (*pos-- != pad) {
195			wpa_printf(MSG_DEBUG, "WPS: Invalid PKCS#5 v2.0 pad "
196				   "string");
197			wpabuf_free(decrypted);
198			return NULL;
199		}
200	}
201	decrypted->used -= pad;
202
203	return decrypted;
204}
205
206
207/**
208 * wps_pin_checksum - Compute PIN checksum
209 * @pin: Seven digit PIN (i.e., eight digit PIN without the checksum digit)
210 * Returns: Checksum digit
211 */
212unsigned int wps_pin_checksum(unsigned int pin)
213{
214	unsigned int accum = 0;
215	while (pin) {
216		accum += 3 * (pin % 10);
217		pin /= 10;
218		accum += pin % 10;
219		pin /= 10;
220	}
221
222	return (10 - accum % 10) % 10;
223}
224
225
226/**
227 * wps_pin_valid - Check whether a PIN has a valid checksum
228 * @pin: Eight digit PIN (i.e., including the checksum digit)
229 * Returns: 1 if checksum digit is valid, or 0 if not
230 */
231unsigned int wps_pin_valid(unsigned int pin)
232{
233	return wps_pin_checksum(pin / 10) == (pin % 10);
234}
235
236
237/**
238 * wps_generate_pin - Generate a random PIN
239 * Returns: Eight digit PIN (i.e., including the checksum digit)
240 */
241unsigned int wps_generate_pin(void)
242{
243	unsigned int val;
244
245	/* Generate seven random digits for the PIN */
246	if (random_get_bytes((unsigned char *) &val, sizeof(val)) < 0) {
247		struct os_time now;
248		os_get_time(&now);
249		val = os_random() ^ now.sec ^ now.usec;
250	}
251	val %= 10000000;
252
253	/* Append checksum digit */
254	return val * 10 + wps_pin_checksum(val);
255}
256
257
258void wps_fail_event(struct wps_context *wps, enum wps_msg_type msg,
259		    u16 config_error, u16 error_indication)
260{
261	union wps_event_data data;
262
263	if (wps->event_cb == NULL)
264		return;
265
266	os_memset(&data, 0, sizeof(data));
267	data.fail.msg = msg;
268	data.fail.config_error = config_error;
269	data.fail.error_indication = error_indication;
270	wps->event_cb(wps->cb_ctx, WPS_EV_FAIL, &data);
271}
272
273
274void wps_success_event(struct wps_context *wps)
275{
276	if (wps->event_cb == NULL)
277		return;
278
279	wps->event_cb(wps->cb_ctx, WPS_EV_SUCCESS, NULL);
280}
281
282
283void wps_pwd_auth_fail_event(struct wps_context *wps, int enrollee, int part)
284{
285	union wps_event_data data;
286
287	if (wps->event_cb == NULL)
288		return;
289
290	os_memset(&data, 0, sizeof(data));
291	data.pwd_auth_fail.enrollee = enrollee;
292	data.pwd_auth_fail.part = part;
293	wps->event_cb(wps->cb_ctx, WPS_EV_PWD_AUTH_FAIL, &data);
294}
295
296
297void wps_pbc_overlap_event(struct wps_context *wps)
298{
299	if (wps->event_cb == NULL)
300		return;
301
302	wps->event_cb(wps->cb_ctx, WPS_EV_PBC_OVERLAP, NULL);
303}
304
305
306void wps_pbc_timeout_event(struct wps_context *wps)
307{
308	if (wps->event_cb == NULL)
309		return;
310
311	wps->event_cb(wps->cb_ctx, WPS_EV_PBC_TIMEOUT, NULL);
312}
313
314
315#ifdef CONFIG_WPS_OOB
316
317static struct wpabuf * wps_get_oob_cred(struct wps_context *wps)
318{
319	struct wps_data data;
320	struct wpabuf *plain;
321
322	plain = wpabuf_alloc(500);
323	if (plain == NULL) {
324		wpa_printf(MSG_ERROR, "WPS: Failed to allocate memory for OOB "
325			   "credential");
326		return NULL;
327	}
328
329	os_memset(&data, 0, sizeof(data));
330	data.wps = wps;
331	data.auth_type = wps->auth_types;
332	data.encr_type = wps->encr_types;
333	if (wps_build_version(plain) ||
334	    wps_build_cred(&data, plain) ||
335	    wps_build_wfa_ext(plain, 0, NULL, 0)) {
336		wpabuf_free(plain);
337		return NULL;
338	}
339
340	return plain;
341}
342
343
344static struct wpabuf * wps_get_oob_dev_pwd(struct wps_context *wps)
345{
346	struct wpabuf *data;
347
348	data = wpabuf_alloc(9 + WPS_OOB_DEVICE_PASSWORD_ATTR_LEN);
349	if (data == NULL) {
350		wpa_printf(MSG_ERROR, "WPS: Failed to allocate memory for OOB "
351			   "device password attribute");
352		return NULL;
353	}
354
355	wpabuf_free(wps->oob_conf.dev_password);
356	wps->oob_conf.dev_password =
357		wpabuf_alloc(WPS_OOB_DEVICE_PASSWORD_LEN * 2 + 1);
358	if (wps->oob_conf.dev_password == NULL) {
359		wpa_printf(MSG_ERROR, "WPS: Failed to allocate memory for OOB "
360			   "device password");
361		wpabuf_free(data);
362		return NULL;
363	}
364
365	if (wps_build_version(data) ||
366	    wps_build_oob_dev_password(data, wps) ||
367	    wps_build_wfa_ext(data, 0, NULL, 0)) {
368		wpa_printf(MSG_ERROR, "WPS: Build OOB device password "
369			   "attribute error");
370		wpabuf_free(data);
371		return NULL;
372	}
373
374	return data;
375}
376
377
378static int wps_parse_oob_dev_pwd(struct wps_context *wps,
379				 struct wpabuf *data)
380{
381	struct oob_conf_data *oob_conf = &wps->oob_conf;
382	struct wps_parse_attr attr;
383	const u8 *pos;
384
385	if (wps_parse_msg(data, &attr) < 0 ||
386	    attr.oob_dev_password == NULL) {
387		wpa_printf(MSG_ERROR, "WPS: OOB device password not found");
388		return -1;
389	}
390
391	pos = attr.oob_dev_password;
392
393	oob_conf->pubkey_hash =
394		wpabuf_alloc_copy(pos, WPS_OOB_PUBKEY_HASH_LEN);
395	if (oob_conf->pubkey_hash == NULL) {
396		wpa_printf(MSG_ERROR, "WPS: Failed to allocate memory for OOB "
397			   "public key hash");
398		return -1;
399	}
400	pos += WPS_OOB_PUBKEY_HASH_LEN;
401
402	wps->oob_dev_pw_id = WPA_GET_BE16(pos);
403	pos += sizeof(wps->oob_dev_pw_id);
404
405	oob_conf->dev_password =
406		wpabuf_alloc(WPS_OOB_DEVICE_PASSWORD_LEN * 2 + 1);
407	if (oob_conf->dev_password == NULL) {
408		wpa_printf(MSG_ERROR, "WPS: Failed to allocate memory for OOB "
409			   "device password");
410		return -1;
411	}
412	wpa_snprintf_hex_uppercase(wpabuf_put(oob_conf->dev_password,
413				   wpabuf_size(oob_conf->dev_password)),
414				   wpabuf_size(oob_conf->dev_password), pos,
415				   WPS_OOB_DEVICE_PASSWORD_LEN);
416
417	return 0;
418}
419
420
421static int wps_parse_oob_cred(struct wps_context *wps, struct wpabuf *data)
422{
423	struct wpabuf msg;
424	struct wps_parse_attr attr;
425	size_t i;
426
427	if (wps_parse_msg(data, &attr) < 0 || attr.num_cred <= 0) {
428		wpa_printf(MSG_ERROR, "WPS: OOB credential not found");
429		return -1;
430	}
431
432	for (i = 0; i < attr.num_cred; i++) {
433		struct wps_credential local_cred;
434		struct wps_parse_attr cattr;
435
436		os_memset(&local_cred, 0, sizeof(local_cred));
437		wpabuf_set(&msg, attr.cred[i], attr.cred_len[i]);
438		if (wps_parse_msg(&msg, &cattr) < 0 ||
439		    wps_process_cred(&cattr, &local_cred)) {
440			wpa_printf(MSG_ERROR, "WPS: Failed to parse OOB "
441				   "credential");
442			return -1;
443		}
444		wps->cred_cb(wps->cb_ctx, &local_cred);
445	}
446
447	return 0;
448}
449
450
451int wps_process_oob(struct wps_context *wps, struct oob_device_data *oob_dev,
452		    int registrar)
453{
454	struct wpabuf *data;
455	int ret, write_f, oob_method = wps->oob_conf.oob_method;
456	void *oob_priv;
457
458	write_f = oob_method == OOB_METHOD_DEV_PWD_E ? !registrar : registrar;
459
460	oob_priv = oob_dev->init_func(wps, oob_dev, registrar);
461	if (oob_priv == NULL) {
462		wpa_printf(MSG_ERROR, "WPS: Failed to initialize OOB device");
463		return -1;
464	}
465
466	if (write_f) {
467		if (oob_method == OOB_METHOD_CRED)
468			data = wps_get_oob_cred(wps);
469		else
470			data = wps_get_oob_dev_pwd(wps);
471
472		ret = 0;
473		if (data == NULL || oob_dev->write_func(oob_priv, data) < 0)
474			ret = -1;
475	} else {
476		data = oob_dev->read_func(oob_priv);
477		if (data == NULL)
478			ret = -1;
479		else {
480			if (oob_method == OOB_METHOD_CRED)
481				ret = wps_parse_oob_cred(wps, data);
482			else
483				ret = wps_parse_oob_dev_pwd(wps, data);
484		}
485	}
486	wpabuf_free(data);
487	oob_dev->deinit_func(oob_priv);
488
489	if (ret < 0) {
490		wpa_printf(MSG_ERROR, "WPS: Failed to process OOB data");
491		return -1;
492	}
493
494	return 0;
495}
496
497
498struct oob_device_data * wps_get_oob_device(char *device_type)
499{
500#ifdef CONFIG_WPS_UFD
501	if (os_strstr(device_type, "ufd") != NULL)
502		return &oob_ufd_device_data;
503#endif /* CONFIG_WPS_UFD */
504#ifdef CONFIG_WPS_NFC
505	if (os_strstr(device_type, "nfc") != NULL)
506		return &oob_nfc_device_data;
507#endif /* CONFIG_WPS_NFC */
508
509	return NULL;
510}
511
512
513#ifdef CONFIG_WPS_NFC
514struct oob_nfc_device_data * wps_get_oob_nfc_device(char *device_name)
515{
516	if (device_name == NULL)
517		return NULL;
518#ifdef CONFIG_WPS_NFC_PN531
519	if (os_strstr(device_name, "pn531") != NULL)
520		return &oob_nfc_pn531_device_data;
521#endif /* CONFIG_WPS_NFC_PN531 */
522
523	return NULL;
524}
525#endif /* CONFIG_WPS_NFC */
526
527
528int wps_get_oob_method(char *method)
529{
530	if (os_strstr(method, "pin-e") != NULL)
531		return OOB_METHOD_DEV_PWD_E;
532	if (os_strstr(method, "pin-r") != NULL)
533		return OOB_METHOD_DEV_PWD_R;
534	if (os_strstr(method, "cred") != NULL)
535		return OOB_METHOD_CRED;
536	return OOB_METHOD_UNKNOWN;
537}
538
539#endif /* CONFIG_WPS_OOB */
540
541
542int wps_dev_type_str2bin(const char *str, u8 dev_type[WPS_DEV_TYPE_LEN])
543{
544	const char *pos;
545
546	/* <categ>-<OUI>-<subcateg> */
547	WPA_PUT_BE16(dev_type, atoi(str));
548	pos = os_strchr(str, '-');
549	if (pos == NULL)
550		return -1;
551	pos++;
552	if (hexstr2bin(pos, &dev_type[2], 4))
553		return -1;
554	pos = os_strchr(pos, '-');
555	if (pos == NULL)
556		return -1;
557	pos++;
558	WPA_PUT_BE16(&dev_type[6], atoi(pos));
559
560
561	return 0;
562}
563
564
565char * wps_dev_type_bin2str(const u8 dev_type[WPS_DEV_TYPE_LEN], char *buf,
566			    size_t buf_len)
567{
568	int ret;
569
570	ret = os_snprintf(buf, buf_len, "%u-%08X-%u",
571			  WPA_GET_BE16(dev_type), WPA_GET_BE32(&dev_type[2]),
572			  WPA_GET_BE16(&dev_type[6]));
573	if (ret < 0 || (unsigned int) ret >= buf_len)
574		return NULL;
575
576	return buf;
577}
578
579
580void uuid_gen_mac_addr(const u8 *mac_addr, u8 *uuid)
581{
582	const u8 *addr[2];
583	size_t len[2];
584	u8 hash[SHA1_MAC_LEN];
585	u8 nsid[16] = {
586		0x52, 0x64, 0x80, 0xf8,
587		0xc9, 0x9b,
588		0x4b, 0xe5,
589		0xa6, 0x55,
590		0x58, 0xed, 0x5f, 0x5d, 0x60, 0x84
591	};
592
593	addr[0] = nsid;
594	len[0] = sizeof(nsid);
595	addr[1] = mac_addr;
596	len[1] = 6;
597	sha1_vector(2, addr, len, hash);
598	os_memcpy(uuid, hash, 16);
599
600	/* Version: 5 = named-based version using SHA-1 */
601	uuid[6] = (5 << 4) | (uuid[6] & 0x0f);
602
603	/* Variant specified in RFC 4122 */
604	uuid[8] = 0x80 | (uuid[8] & 0x3f);
605}
606
607
608u16 wps_config_methods_str2bin(const char *str)
609{
610	u16 methods = 0;
611
612	if (str == NULL) {
613		/* Default to enabling methods based on build configuration */
614		methods |= WPS_CONFIG_DISPLAY | WPS_CONFIG_KEYPAD;
615#ifdef CONFIG_WPS2
616		methods |= WPS_CONFIG_VIRT_DISPLAY;
617#endif /* CONFIG_WPS2 */
618#ifdef CONFIG_WPS_UFD
619		methods |= WPS_CONFIG_USBA;
620#endif /* CONFIG_WPS_UFD */
621#ifdef CONFIG_WPS_NFC
622		methods |= WPS_CONFIG_NFC_INTERFACE;
623#endif /* CONFIG_WPS_NFC */
624	} else {
625		if (os_strstr(str, "usba"))
626			methods |= WPS_CONFIG_USBA;
627		if (os_strstr(str, "ethernet"))
628			methods |= WPS_CONFIG_ETHERNET;
629		if (os_strstr(str, "label"))
630			methods |= WPS_CONFIG_LABEL;
631		if (os_strstr(str, "display"))
632			methods |= WPS_CONFIG_DISPLAY;
633		if (os_strstr(str, "ext_nfc_token"))
634			methods |= WPS_CONFIG_EXT_NFC_TOKEN;
635		if (os_strstr(str, "int_nfc_token"))
636			methods |= WPS_CONFIG_INT_NFC_TOKEN;
637		if (os_strstr(str, "nfc_interface"))
638			methods |= WPS_CONFIG_NFC_INTERFACE;
639		if (os_strstr(str, "push_button"))
640			methods |= WPS_CONFIG_PUSHBUTTON;
641		if (os_strstr(str, "keypad"))
642			methods |= WPS_CONFIG_KEYPAD;
643#ifdef CONFIG_WPS2
644		if (os_strstr(str, "virtual_display"))
645			methods |= WPS_CONFIG_VIRT_DISPLAY;
646		if (os_strstr(str, "physical_display"))
647			methods |= WPS_CONFIG_PHY_DISPLAY;
648		if (os_strstr(str, "virtual_push_button"))
649			methods |= WPS_CONFIG_VIRT_PUSHBUTTON;
650		if (os_strstr(str, "physical_push_button"))
651			methods |= WPS_CONFIG_PHY_PUSHBUTTON;
652#endif /* CONFIG_WPS2 */
653	}
654
655	return methods;
656}
657
658
659struct wpabuf * wps_build_wsc_ack(struct wps_data *wps)
660{
661	struct wpabuf *msg;
662
663	wpa_printf(MSG_DEBUG, "WPS: Building Message WSC_ACK");
664
665	msg = wpabuf_alloc(1000);
666	if (msg == NULL)
667		return NULL;
668
669	if (wps_build_version(msg) ||
670	    wps_build_msg_type(msg, WPS_WSC_ACK) ||
671	    wps_build_enrollee_nonce(wps, msg) ||
672	    wps_build_registrar_nonce(wps, msg) ||
673	    wps_build_wfa_ext(msg, 0, NULL, 0)) {
674		wpabuf_free(msg);
675		return NULL;
676	}
677
678	return msg;
679}
680
681
682struct wpabuf * wps_build_wsc_nack(struct wps_data *wps)
683{
684	struct wpabuf *msg;
685
686	wpa_printf(MSG_DEBUG, "WPS: Building Message WSC_NACK");
687
688	msg = wpabuf_alloc(1000);
689	if (msg == NULL)
690		return NULL;
691
692	if (wps_build_version(msg) ||
693	    wps_build_msg_type(msg, WPS_WSC_NACK) ||
694	    wps_build_enrollee_nonce(wps, msg) ||
695	    wps_build_registrar_nonce(wps, msg) ||
696	    wps_build_config_error(msg, wps->config_error) ||
697	    wps_build_wfa_ext(msg, 0, NULL, 0)) {
698		wpabuf_free(msg);
699		return NULL;
700	}
701
702	return msg;
703}
704