wps_common.c revision 849734c8d1847920ed7042463f7480b1e0c1dfea
1/*
2 * Wi-Fi Protected Setup - common functionality
3 * Copyright (c) 2008-2012, Jouni Malinen <j@w1.fi>
4 *
5 * This software may be distributed under the terms of the BSD license.
6 * See README for more details.
7 */
8
9#include "includes.h"
10
11#include "common.h"
12#include "common/defs.h"
13#include "common/ieee802_11_common.h"
14#include "crypto/aes_wrap.h"
15#include "crypto/crypto.h"
16#include "crypto/dh_group5.h"
17#include "crypto/sha1.h"
18#include "crypto/sha256.h"
19#include "crypto/random.h"
20#include "wps_i.h"
21#include "wps_dev_attr.h"
22
23
24void wps_kdf(const u8 *key, const u8 *label_prefix, size_t label_prefix_len,
25	     const char *label, u8 *res, size_t res_len)
26{
27	u8 i_buf[4], key_bits[4];
28	const u8 *addr[4];
29	size_t len[4];
30	int i, iter;
31	u8 hash[SHA256_MAC_LEN], *opos;
32	size_t left;
33
34	WPA_PUT_BE32(key_bits, res_len * 8);
35
36	addr[0] = i_buf;
37	len[0] = sizeof(i_buf);
38	addr[1] = label_prefix;
39	len[1] = label_prefix_len;
40	addr[2] = (const u8 *) label;
41	len[2] = os_strlen(label);
42	addr[3] = key_bits;
43	len[3] = sizeof(key_bits);
44
45	iter = (res_len + SHA256_MAC_LEN - 1) / SHA256_MAC_LEN;
46	opos = res;
47	left = res_len;
48
49	for (i = 1; i <= iter; i++) {
50		WPA_PUT_BE32(i_buf, i);
51		hmac_sha256_vector(key, SHA256_MAC_LEN, 4, addr, len, hash);
52		if (i < iter) {
53			os_memcpy(opos, hash, SHA256_MAC_LEN);
54			opos += SHA256_MAC_LEN;
55			left -= SHA256_MAC_LEN;
56		} else
57			os_memcpy(opos, hash, left);
58	}
59}
60
61
62int wps_derive_keys(struct wps_data *wps)
63{
64	struct wpabuf *pubkey, *dh_shared;
65	u8 dhkey[SHA256_MAC_LEN], kdk[SHA256_MAC_LEN];
66	const u8 *addr[3];
67	size_t len[3];
68	u8 keys[WPS_AUTHKEY_LEN + WPS_KEYWRAPKEY_LEN + WPS_EMSK_LEN];
69
70	if (wps->dh_privkey == NULL) {
71		wpa_printf(MSG_DEBUG, "WPS: Own DH private key not available");
72		return -1;
73	}
74
75	pubkey = wps->registrar ? wps->dh_pubkey_e : wps->dh_pubkey_r;
76	if (pubkey == NULL) {
77		wpa_printf(MSG_DEBUG, "WPS: Peer DH public key not available");
78		return -1;
79	}
80
81	wpa_hexdump_buf_key(MSG_DEBUG, "WPS: DH Private Key", wps->dh_privkey);
82	wpa_hexdump_buf(MSG_DEBUG, "WPS: DH peer Public Key", pubkey);
83	dh_shared = dh5_derive_shared(wps->dh_ctx, pubkey, wps->dh_privkey);
84	dh5_free(wps->dh_ctx);
85	wps->dh_ctx = NULL;
86	dh_shared = wpabuf_zeropad(dh_shared, 192);
87	if (dh_shared == NULL) {
88		wpa_printf(MSG_DEBUG, "WPS: Failed to derive DH shared key");
89		return -1;
90	}
91
92	/* Own DH private key is not needed anymore */
93	wpabuf_clear_free(wps->dh_privkey);
94	wps->dh_privkey = NULL;
95
96	wpa_hexdump_buf_key(MSG_DEBUG, "WPS: DH shared key", dh_shared);
97
98	/* DHKey = SHA-256(g^AB mod p) */
99	addr[0] = wpabuf_head(dh_shared);
100	len[0] = wpabuf_len(dh_shared);
101	sha256_vector(1, addr, len, dhkey);
102	wpa_hexdump_key(MSG_DEBUG, "WPS: DHKey", dhkey, sizeof(dhkey));
103	wpabuf_clear_free(dh_shared);
104
105	/* KDK = HMAC-SHA-256_DHKey(N1 || EnrolleeMAC || N2) */
106	addr[0] = wps->nonce_e;
107	len[0] = WPS_NONCE_LEN;
108	addr[1] = wps->mac_addr_e;
109	len[1] = ETH_ALEN;
110	addr[2] = wps->nonce_r;
111	len[2] = WPS_NONCE_LEN;
112	hmac_sha256_vector(dhkey, sizeof(dhkey), 3, addr, len, kdk);
113	wpa_hexdump_key(MSG_DEBUG, "WPS: KDK", kdk, sizeof(kdk));
114
115	wps_kdf(kdk, NULL, 0, "Wi-Fi Easy and Secure Key Derivation",
116		keys, sizeof(keys));
117	os_memcpy(wps->authkey, keys, WPS_AUTHKEY_LEN);
118	os_memcpy(wps->keywrapkey, keys + WPS_AUTHKEY_LEN, WPS_KEYWRAPKEY_LEN);
119	os_memcpy(wps->emsk, keys + WPS_AUTHKEY_LEN + WPS_KEYWRAPKEY_LEN,
120		  WPS_EMSK_LEN);
121
122	wpa_hexdump_key(MSG_DEBUG, "WPS: AuthKey",
123			wps->authkey, WPS_AUTHKEY_LEN);
124	wpa_hexdump_key(MSG_DEBUG, "WPS: KeyWrapKey",
125			wps->keywrapkey, WPS_KEYWRAPKEY_LEN);
126	wpa_hexdump_key(MSG_DEBUG, "WPS: EMSK", wps->emsk, WPS_EMSK_LEN);
127
128	return 0;
129}
130
131
132int wps_derive_psk(struct wps_data *wps, const u8 *dev_passwd,
133		   size_t dev_passwd_len)
134{
135	u8 hash[SHA256_MAC_LEN];
136
137	if (hmac_sha256(wps->authkey, WPS_AUTHKEY_LEN, dev_passwd,
138			(dev_passwd_len + 1) / 2, hash) < 0)
139		return -1;
140	os_memcpy(wps->psk1, hash, WPS_PSK_LEN);
141	if (hmac_sha256(wps->authkey, WPS_AUTHKEY_LEN,
142			dev_passwd + (dev_passwd_len + 1) / 2,
143			dev_passwd_len / 2, hash) < 0)
144		return -1;
145	os_memcpy(wps->psk2, hash, WPS_PSK_LEN);
146
147	wpa_hexdump_ascii_key(MSG_DEBUG, "WPS: Device Password",
148			      dev_passwd, dev_passwd_len);
149	wpa_hexdump_key(MSG_DEBUG, "WPS: PSK1", wps->psk1, WPS_PSK_LEN);
150	wpa_hexdump_key(MSG_DEBUG, "WPS: PSK2", wps->psk2, WPS_PSK_LEN);
151	return 0;
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_clear_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_clear_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_clear_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 */
241int wps_generate_pin(unsigned int *pin)
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		return -1;
248	val %= 10000000;
249
250	/* Append checksum digit */
251	*pin = val * 10 + wps_pin_checksum(val);
252	return 0;
253}
254
255
256int wps_pin_str_valid(const char *pin)
257{
258	const char *p;
259	size_t len;
260
261	p = pin;
262	while (*p >= '0' && *p <= '9')
263		p++;
264	if (*p != '\0')
265		return 0;
266
267	len = p - pin;
268	return len == 4 || len == 8;
269}
270
271
272void wps_fail_event(struct wps_context *wps, enum wps_msg_type msg,
273		    u16 config_error, u16 error_indication, const u8 *mac_addr)
274{
275	union wps_event_data data;
276
277	if (wps->event_cb == NULL)
278		return;
279
280	os_memset(&data, 0, sizeof(data));
281	data.fail.msg = msg;
282	data.fail.config_error = config_error;
283	data.fail.error_indication = error_indication;
284	os_memcpy(data.fail.peer_macaddr, mac_addr, ETH_ALEN);
285	wps->event_cb(wps->cb_ctx, WPS_EV_FAIL, &data);
286}
287
288
289void wps_success_event(struct wps_context *wps, const u8 *mac_addr)
290{
291	union wps_event_data data;
292
293	if (wps->event_cb == NULL)
294		return;
295
296	os_memset(&data, 0, sizeof(data));
297	os_memcpy(data.success.peer_macaddr, mac_addr, ETH_ALEN);
298	wps->event_cb(wps->cb_ctx, WPS_EV_SUCCESS, &data);
299}
300
301
302void wps_pwd_auth_fail_event(struct wps_context *wps, int enrollee, int part,
303			     const u8 *mac_addr)
304{
305	union wps_event_data data;
306
307	if (wps->event_cb == NULL)
308		return;
309
310	os_memset(&data, 0, sizeof(data));
311	data.pwd_auth_fail.enrollee = enrollee;
312	data.pwd_auth_fail.part = part;
313	os_memcpy(data.pwd_auth_fail.peer_macaddr, mac_addr, ETH_ALEN);
314	wps->event_cb(wps->cb_ctx, WPS_EV_PWD_AUTH_FAIL, &data);
315}
316
317
318void wps_pbc_overlap_event(struct wps_context *wps)
319{
320	if (wps->event_cb == NULL)
321		return;
322
323	wps->event_cb(wps->cb_ctx, WPS_EV_PBC_OVERLAP, NULL);
324}
325
326
327void wps_pbc_timeout_event(struct wps_context *wps)
328{
329	if (wps->event_cb == NULL)
330		return;
331
332	wps->event_cb(wps->cb_ctx, WPS_EV_PBC_TIMEOUT, NULL);
333}
334
335
336void wps_pbc_active_event(struct wps_context *wps)
337{
338	if (wps->event_cb == NULL)
339		return;
340
341	wps->event_cb(wps->cb_ctx, WPS_EV_PBC_ACTIVE, NULL);
342}
343
344
345void wps_pbc_disable_event(struct wps_context *wps)
346{
347	if (wps->event_cb == NULL)
348		return;
349
350	wps->event_cb(wps->cb_ctx, WPS_EV_PBC_DISABLE, NULL);
351}
352
353
354#ifdef CONFIG_WPS_OOB
355
356struct wpabuf * wps_get_oob_cred(struct wps_context *wps, int rf_band,
357				 int channel)
358{
359	struct wps_data data;
360	struct wpabuf *plain;
361
362	plain = wpabuf_alloc(500);
363	if (plain == NULL) {
364		wpa_printf(MSG_ERROR, "WPS: Failed to allocate memory for OOB "
365			   "credential");
366		return NULL;
367	}
368
369	os_memset(&data, 0, sizeof(data));
370	data.wps = wps;
371	data.auth_type = wps->auth_types;
372	data.encr_type = wps->encr_types;
373	if (wps_build_cred(&data, plain) ||
374	    (rf_band && wps_build_rf_bands_attr(plain, rf_band)) ||
375	    (channel && wps_build_ap_channel(plain, channel)) ||
376	    wps_build_mac_addr(plain, wps->dev.mac_addr) ||
377	    wps_build_wfa_ext(plain, 0, NULL, 0)) {
378		os_free(data.new_psk);
379		wpabuf_clear_free(plain);
380		return NULL;
381	}
382
383	if (wps->wps_state == WPS_STATE_NOT_CONFIGURED && data.new_psk &&
384	    wps->ap) {
385		struct wps_credential cred;
386
387		wpa_printf(MSG_DEBUG, "WPS: Moving to Configured state based "
388			   "on credential token generation");
389
390		os_memset(&cred, 0, sizeof(cred));
391		os_memcpy(cred.ssid, wps->ssid, wps->ssid_len);
392		cred.ssid_len = wps->ssid_len;
393		cred.auth_type = WPS_AUTH_WPAPSK | WPS_AUTH_WPA2PSK;
394		cred.encr_type = WPS_ENCR_TKIP | WPS_ENCR_AES;
395		os_memcpy(cred.key, data.new_psk, data.new_psk_len);
396		cred.key_len = data.new_psk_len;
397
398		wps->wps_state = WPS_STATE_CONFIGURED;
399		wpa_hexdump_ascii_key(MSG_DEBUG,
400				      "WPS: Generated random passphrase",
401				      data.new_psk, data.new_psk_len);
402		if (wps->cred_cb)
403			wps->cred_cb(wps->cb_ctx, &cred);
404	}
405
406	os_free(data.new_psk);
407
408	return plain;
409}
410
411
412struct wpabuf * wps_build_nfc_pw_token(u16 dev_pw_id,
413				       const struct wpabuf *pubkey,
414				       const struct wpabuf *dev_pw)
415{
416	struct wpabuf *data;
417
418	data = wpabuf_alloc(200);
419	if (data == NULL)
420		return NULL;
421
422	if (wps_build_oob_dev_pw(data, dev_pw_id, pubkey,
423				 wpabuf_head(dev_pw), wpabuf_len(dev_pw)) ||
424	    wps_build_wfa_ext(data, 0, NULL, 0)) {
425		wpa_printf(MSG_ERROR, "WPS: Failed to build NFC password "
426			   "token");
427		wpabuf_clear_free(data);
428		return NULL;
429	}
430
431	return data;
432}
433
434
435int wps_oob_use_cred(struct wps_context *wps, struct wps_parse_attr *attr)
436{
437	struct wpabuf msg;
438	size_t i;
439
440	for (i = 0; i < attr->num_cred; i++) {
441		struct wps_credential local_cred;
442		struct wps_parse_attr cattr;
443
444		os_memset(&local_cred, 0, sizeof(local_cred));
445		wpabuf_set(&msg, attr->cred[i], attr->cred_len[i]);
446		if (wps_parse_msg(&msg, &cattr) < 0 ||
447		    wps_process_cred(&cattr, &local_cred)) {
448			wpa_printf(MSG_ERROR, "WPS: Failed to parse OOB "
449				   "credential");
450			return -1;
451		}
452		wps->cred_cb(wps->cb_ctx, &local_cred);
453	}
454
455	return 0;
456}
457
458
459#endif /* CONFIG_WPS_OOB */
460
461
462int wps_dev_type_str2bin(const char *str, u8 dev_type[WPS_DEV_TYPE_LEN])
463{
464	const char *pos;
465
466	/* <categ>-<OUI>-<subcateg> */
467	WPA_PUT_BE16(dev_type, atoi(str));
468	pos = os_strchr(str, '-');
469	if (pos == NULL)
470		return -1;
471	pos++;
472	if (hexstr2bin(pos, &dev_type[2], 4))
473		return -1;
474	pos = os_strchr(pos, '-');
475	if (pos == NULL)
476		return -1;
477	pos++;
478	WPA_PUT_BE16(&dev_type[6], atoi(pos));
479
480
481	return 0;
482}
483
484
485char * wps_dev_type_bin2str(const u8 dev_type[WPS_DEV_TYPE_LEN], char *buf,
486			    size_t buf_len)
487{
488	int ret;
489
490	ret = os_snprintf(buf, buf_len, "%u-%08X-%u",
491			  WPA_GET_BE16(dev_type), WPA_GET_BE32(&dev_type[2]),
492			  WPA_GET_BE16(&dev_type[6]));
493	if (os_snprintf_error(buf_len, ret))
494		return NULL;
495
496	return buf;
497}
498
499
500void uuid_gen_mac_addr(const u8 *mac_addr, u8 *uuid)
501{
502	const u8 *addr[2];
503	size_t len[2];
504	u8 hash[SHA1_MAC_LEN];
505	u8 nsid[16] = {
506		0x52, 0x64, 0x80, 0xf8,
507		0xc9, 0x9b,
508		0x4b, 0xe5,
509		0xa6, 0x55,
510		0x58, 0xed, 0x5f, 0x5d, 0x60, 0x84
511	};
512
513	addr[0] = nsid;
514	len[0] = sizeof(nsid);
515	addr[1] = mac_addr;
516	len[1] = 6;
517	sha1_vector(2, addr, len, hash);
518	os_memcpy(uuid, hash, 16);
519
520	/* Version: 5 = named-based version using SHA-1 */
521	uuid[6] = (5 << 4) | (uuid[6] & 0x0f);
522
523	/* Variant specified in RFC 4122 */
524	uuid[8] = 0x80 | (uuid[8] & 0x3f);
525}
526
527
528u16 wps_config_methods_str2bin(const char *str)
529{
530	u16 methods = 0;
531
532	if (str == NULL || str[0] == '\0') {
533		/* Default to enabling methods based on build configuration */
534		methods |= WPS_CONFIG_DISPLAY | WPS_CONFIG_KEYPAD;
535		methods |= WPS_CONFIG_VIRT_DISPLAY;
536#ifdef CONFIG_WPS_NFC
537		methods |= WPS_CONFIG_NFC_INTERFACE;
538#endif /* CONFIG_WPS_NFC */
539#ifdef CONFIG_P2P
540		methods |= WPS_CONFIG_P2PS;
541#endif /* CONFIG_P2P */
542	} else {
543		if (os_strstr(str, "ethernet"))
544			methods |= WPS_CONFIG_ETHERNET;
545		if (os_strstr(str, "label"))
546			methods |= WPS_CONFIG_LABEL;
547		if (os_strstr(str, "display"))
548			methods |= WPS_CONFIG_DISPLAY;
549		if (os_strstr(str, "ext_nfc_token"))
550			methods |= WPS_CONFIG_EXT_NFC_TOKEN;
551		if (os_strstr(str, "int_nfc_token"))
552			methods |= WPS_CONFIG_INT_NFC_TOKEN;
553		if (os_strstr(str, "nfc_interface"))
554			methods |= WPS_CONFIG_NFC_INTERFACE;
555		if (os_strstr(str, "push_button"))
556			methods |= WPS_CONFIG_PUSHBUTTON;
557		if (os_strstr(str, "keypad"))
558			methods |= WPS_CONFIG_KEYPAD;
559		if (os_strstr(str, "virtual_display"))
560			methods |= WPS_CONFIG_VIRT_DISPLAY;
561		if (os_strstr(str, "physical_display"))
562			methods |= WPS_CONFIG_PHY_DISPLAY;
563		if (os_strstr(str, "virtual_push_button"))
564			methods |= WPS_CONFIG_VIRT_PUSHBUTTON;
565		if (os_strstr(str, "physical_push_button"))
566			methods |= WPS_CONFIG_PHY_PUSHBUTTON;
567		if (os_strstr(str, "p2ps"))
568			methods |= WPS_CONFIG_P2PS;
569	}
570
571	return methods;
572}
573
574
575struct wpabuf * wps_build_wsc_ack(struct wps_data *wps)
576{
577	struct wpabuf *msg;
578
579	wpa_printf(MSG_DEBUG, "WPS: Building Message WSC_ACK");
580
581	msg = wpabuf_alloc(1000);
582	if (msg == NULL)
583		return NULL;
584
585	if (wps_build_version(msg) ||
586	    wps_build_msg_type(msg, WPS_WSC_ACK) ||
587	    wps_build_enrollee_nonce(wps, msg) ||
588	    wps_build_registrar_nonce(wps, msg) ||
589	    wps_build_wfa_ext(msg, 0, NULL, 0)) {
590		wpabuf_free(msg);
591		return NULL;
592	}
593
594	return msg;
595}
596
597
598struct wpabuf * wps_build_wsc_nack(struct wps_data *wps)
599{
600	struct wpabuf *msg;
601
602	wpa_printf(MSG_DEBUG, "WPS: Building Message WSC_NACK");
603
604	msg = wpabuf_alloc(1000);
605	if (msg == NULL)
606		return NULL;
607
608	if (wps_build_version(msg) ||
609	    wps_build_msg_type(msg, WPS_WSC_NACK) ||
610	    wps_build_enrollee_nonce(wps, msg) ||
611	    wps_build_registrar_nonce(wps, msg) ||
612	    wps_build_config_error(msg, wps->config_error) ||
613	    wps_build_wfa_ext(msg, 0, NULL, 0)) {
614		wpabuf_free(msg);
615		return NULL;
616	}
617
618	return msg;
619}
620
621
622#ifdef CONFIG_WPS_NFC
623
624struct wpabuf * wps_nfc_token_build(int ndef, int id, struct wpabuf *pubkey,
625				    struct wpabuf *dev_pw)
626{
627	struct wpabuf *ret;
628
629	if (pubkey == NULL || dev_pw == NULL)
630		return NULL;
631
632	ret = wps_build_nfc_pw_token(id, pubkey, dev_pw);
633	if (ndef && ret) {
634		struct wpabuf *tmp;
635		tmp = ndef_build_wifi(ret);
636		wpabuf_free(ret);
637		if (tmp == NULL)
638			return NULL;
639		ret = tmp;
640	}
641
642	return ret;
643}
644
645
646int wps_nfc_gen_dh(struct wpabuf **pubkey, struct wpabuf **privkey)
647{
648	struct wpabuf *priv = NULL, *pub = NULL;
649	void *dh_ctx;
650
651	dh_ctx = dh5_init(&priv, &pub);
652	if (dh_ctx == NULL)
653		return -1;
654	pub = wpabuf_zeropad(pub, 192);
655	if (pub == NULL) {
656		wpabuf_free(priv);
657		return -1;
658	}
659	wpa_hexdump_buf(MSG_DEBUG, "WPS: Generated new DH pubkey", pub);
660	dh5_free(dh_ctx);
661
662	wpabuf_free(*pubkey);
663	*pubkey = pub;
664	wpabuf_clear_free(*privkey);
665	*privkey = priv;
666
667	return 0;
668}
669
670
671struct wpabuf * wps_nfc_token_gen(int ndef, int *id, struct wpabuf **pubkey,
672				  struct wpabuf **privkey,
673				  struct wpabuf **dev_pw)
674{
675	struct wpabuf *pw;
676	u16 val;
677
678	pw = wpabuf_alloc(WPS_OOB_DEVICE_PASSWORD_LEN);
679	if (pw == NULL)
680		return NULL;
681
682	if (random_get_bytes(wpabuf_put(pw, WPS_OOB_DEVICE_PASSWORD_LEN),
683			     WPS_OOB_DEVICE_PASSWORD_LEN) ||
684	    random_get_bytes((u8 *) &val, sizeof(val))) {
685		wpabuf_free(pw);
686		return NULL;
687	}
688
689	if (wps_nfc_gen_dh(pubkey, privkey) < 0) {
690		wpabuf_free(pw);
691		return NULL;
692	}
693
694	*id = 0x10 + val % 0xfff0;
695	wpabuf_clear_free(*dev_pw);
696	*dev_pw = pw;
697
698	return wps_nfc_token_build(ndef, *id, *pubkey, *dev_pw);
699}
700
701
702struct wpabuf * wps_build_nfc_handover_req(struct wps_context *ctx,
703					   struct wpabuf *nfc_dh_pubkey)
704{
705	struct wpabuf *msg;
706	void *len;
707
708	if (ctx == NULL)
709		return NULL;
710
711	wpa_printf(MSG_DEBUG, "WPS: Building attributes for NFC connection "
712		   "handover request");
713
714	if (nfc_dh_pubkey == NULL) {
715		wpa_printf(MSG_DEBUG, "WPS: No NFC OOB Device Password "
716			   "configured");
717		return NULL;
718	}
719
720	msg = wpabuf_alloc(1000);
721	if (msg == NULL)
722		return msg;
723	len = wpabuf_put(msg, 2);
724
725	if (wps_build_oob_dev_pw(msg, DEV_PW_NFC_CONNECTION_HANDOVER,
726				 nfc_dh_pubkey, NULL, 0) ||
727	    wps_build_uuid_e(msg, ctx->uuid) ||
728	    wps_build_wfa_ext(msg, 0, NULL, 0)) {
729		wpabuf_free(msg);
730		return NULL;
731	}
732
733	WPA_PUT_BE16(len, wpabuf_len(msg) - 2);
734
735	return msg;
736}
737
738
739static int wps_build_ssid(struct wpabuf *msg, struct wps_context *wps)
740{
741	wpa_printf(MSG_DEBUG, "WPS:  * SSID");
742	wpa_hexdump_ascii(MSG_DEBUG, "WPS: SSID in Connection Handover Select",
743			  wps->ssid, wps->ssid_len);
744	wpabuf_put_be16(msg, ATTR_SSID);
745	wpabuf_put_be16(msg, wps->ssid_len);
746	wpabuf_put_data(msg, wps->ssid, wps->ssid_len);
747	return 0;
748}
749
750
751static int wps_build_ap_freq(struct wpabuf *msg, int freq)
752{
753	enum hostapd_hw_mode mode;
754	u8 channel, rf_band;
755	u16 ap_channel;
756
757	if (freq <= 0)
758		return 0;
759
760	mode = ieee80211_freq_to_chan(freq, &channel);
761	if (mode == NUM_HOSTAPD_MODES)
762		return 0; /* Unknown channel */
763
764	if (mode == HOSTAPD_MODE_IEEE80211G || mode == HOSTAPD_MODE_IEEE80211B)
765		rf_band = WPS_RF_24GHZ;
766	else if (mode == HOSTAPD_MODE_IEEE80211A)
767		rf_band = WPS_RF_50GHZ;
768	else if (mode == HOSTAPD_MODE_IEEE80211AD)
769		rf_band = WPS_RF_60GHZ;
770	else
771		return 0; /* Unknown band */
772	ap_channel = channel;
773
774	if (wps_build_rf_bands_attr(msg, rf_band) ||
775	    wps_build_ap_channel(msg, ap_channel))
776		return -1;
777
778	return 0;
779}
780
781
782struct wpabuf * wps_build_nfc_handover_sel(struct wps_context *ctx,
783					   struct wpabuf *nfc_dh_pubkey,
784					   const u8 *bssid, int freq)
785{
786	struct wpabuf *msg;
787	void *len;
788
789	if (ctx == NULL)
790		return NULL;
791
792	wpa_printf(MSG_DEBUG, "WPS: Building attributes for NFC connection "
793		   "handover select");
794
795	if (nfc_dh_pubkey == NULL) {
796		wpa_printf(MSG_DEBUG, "WPS: No NFC OOB Device Password "
797			   "configured");
798		return NULL;
799	}
800
801	msg = wpabuf_alloc(1000);
802	if (msg == NULL)
803		return msg;
804	len = wpabuf_put(msg, 2);
805
806	if (wps_build_oob_dev_pw(msg, DEV_PW_NFC_CONNECTION_HANDOVER,
807				 nfc_dh_pubkey, NULL, 0) ||
808	    wps_build_ssid(msg, ctx) ||
809	    wps_build_ap_freq(msg, freq) ||
810	    (bssid && wps_build_mac_addr(msg, bssid)) ||
811	    wps_build_wfa_ext(msg, 0, NULL, 0)) {
812		wpabuf_free(msg);
813		return NULL;
814	}
815
816	WPA_PUT_BE16(len, wpabuf_len(msg) - 2);
817
818	return msg;
819}
820
821
822struct wpabuf * wps_build_nfc_handover_req_p2p(struct wps_context *ctx,
823					       struct wpabuf *nfc_dh_pubkey)
824{
825	struct wpabuf *msg;
826
827	if (ctx == NULL)
828		return NULL;
829
830	wpa_printf(MSG_DEBUG, "WPS: Building attributes for NFC connection "
831		   "handover request (P2P)");
832
833	if (nfc_dh_pubkey == NULL) {
834		wpa_printf(MSG_DEBUG, "WPS: No NFC DH Public Key configured");
835		return NULL;
836	}
837
838	msg = wpabuf_alloc(1000);
839	if (msg == NULL)
840		return msg;
841
842	if (wps_build_manufacturer(&ctx->dev, msg) ||
843	    wps_build_model_name(&ctx->dev, msg) ||
844	    wps_build_model_number(&ctx->dev, msg) ||
845	    wps_build_oob_dev_pw(msg, DEV_PW_NFC_CONNECTION_HANDOVER,
846				 nfc_dh_pubkey, NULL, 0) ||
847	    wps_build_rf_bands(&ctx->dev, msg, 0) ||
848	    wps_build_serial_number(&ctx->dev, msg) ||
849	    wps_build_uuid_e(msg, ctx->uuid) ||
850	    wps_build_wfa_ext(msg, 0, NULL, 0)) {
851		wpabuf_free(msg);
852		return NULL;
853	}
854
855	return msg;
856}
857
858
859struct wpabuf * wps_build_nfc_handover_sel_p2p(struct wps_context *ctx,
860					       int nfc_dev_pw_id,
861					       struct wpabuf *nfc_dh_pubkey,
862					       struct wpabuf *nfc_dev_pw)
863{
864	struct wpabuf *msg;
865	const u8 *dev_pw;
866	size_t dev_pw_len;
867
868	if (ctx == NULL)
869		return NULL;
870
871	wpa_printf(MSG_DEBUG, "WPS: Building attributes for NFC connection "
872		   "handover select (P2P)");
873
874	if (nfc_dh_pubkey == NULL ||
875	    (nfc_dev_pw_id != DEV_PW_NFC_CONNECTION_HANDOVER &&
876	     nfc_dev_pw == NULL)) {
877		wpa_printf(MSG_DEBUG, "WPS: No NFC OOB Device Password "
878			   "configured");
879		return NULL;
880	}
881
882	msg = wpabuf_alloc(1000);
883	if (msg == NULL)
884		return msg;
885
886	if (nfc_dev_pw) {
887		dev_pw = wpabuf_head(nfc_dev_pw);
888		dev_pw_len = wpabuf_len(nfc_dev_pw);
889	} else {
890		dev_pw = NULL;
891		dev_pw_len = 0;
892	}
893
894	if (wps_build_manufacturer(&ctx->dev, msg) ||
895	    wps_build_model_name(&ctx->dev, msg) ||
896	    wps_build_model_number(&ctx->dev, msg) ||
897	    wps_build_oob_dev_pw(msg, nfc_dev_pw_id, nfc_dh_pubkey,
898				 dev_pw, dev_pw_len) ||
899	    wps_build_rf_bands(&ctx->dev, msg, 0) ||
900	    wps_build_serial_number(&ctx->dev, msg) ||
901	    wps_build_uuid_e(msg, ctx->uuid) ||
902	    wps_build_wfa_ext(msg, 0, NULL, 0)) {
903		wpabuf_free(msg);
904		return NULL;
905	}
906
907	return msg;
908}
909
910#endif /* CONFIG_WPS_NFC */
911