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 "crypto/aes_wrap.h"
13 #include "crypto/crypto.h"
14 #include "crypto/dh_group5.h"
15 #include "crypto/sha1.h"
16 #include "crypto/sha256.h"
17 #include "crypto/random.h"
18 #include "wps_i.h"
19
20
wps_kdf(const u8 * key,const u8 * label_prefix,size_t label_prefix_len,const char * label,u8 * res,size_t res_len)21 void wps_kdf(const u8 *key, const u8 *label_prefix, size_t label_prefix_len,
22 const char *label, u8 *res, size_t res_len)
23 {
24 u8 i_buf[4], key_bits[4];
25 const u8 *addr[4];
26 size_t len[4];
27 int i, iter;
28 u8 hash[SHA256_MAC_LEN], *opos;
29 size_t left;
30
31 WPA_PUT_BE32(key_bits, res_len * 8);
32
33 addr[0] = i_buf;
34 len[0] = sizeof(i_buf);
35 addr[1] = label_prefix;
36 len[1] = label_prefix_len;
37 addr[2] = (const u8 *) label;
38 len[2] = os_strlen(label);
39 addr[3] = key_bits;
40 len[3] = sizeof(key_bits);
41
42 iter = (res_len + SHA256_MAC_LEN - 1) / SHA256_MAC_LEN;
43 opos = res;
44 left = res_len;
45
46 for (i = 1; i <= iter; i++) {
47 WPA_PUT_BE32(i_buf, i);
48 hmac_sha256_vector(key, SHA256_MAC_LEN, 4, addr, len, hash);
49 if (i < iter) {
50 os_memcpy(opos, hash, SHA256_MAC_LEN);
51 opos += SHA256_MAC_LEN;
52 left -= SHA256_MAC_LEN;
53 } else
54 os_memcpy(opos, hash, left);
55 }
56 }
57
58
wps_derive_keys(struct wps_data * wps)59 int wps_derive_keys(struct wps_data *wps)
60 {
61 struct wpabuf *pubkey, *dh_shared;
62 u8 dhkey[SHA256_MAC_LEN], kdk[SHA256_MAC_LEN];
63 const u8 *addr[3];
64 size_t len[3];
65 u8 keys[WPS_AUTHKEY_LEN + WPS_KEYWRAPKEY_LEN + WPS_EMSK_LEN];
66
67 if (wps->dh_privkey == NULL) {
68 wpa_printf(MSG_DEBUG, "WPS: Own DH private key not available");
69 return -1;
70 }
71
72 pubkey = wps->registrar ? wps->dh_pubkey_e : wps->dh_pubkey_r;
73 if (pubkey == NULL) {
74 wpa_printf(MSG_DEBUG, "WPS: Peer DH public key not available");
75 return -1;
76 }
77
78 wpa_hexdump_buf_key(MSG_DEBUG, "WPS: DH Private Key", wps->dh_privkey);
79 wpa_hexdump_buf(MSG_DEBUG, "WPS: DH peer Public Key", pubkey);
80 dh_shared = dh5_derive_shared(wps->dh_ctx, pubkey, wps->dh_privkey);
81 dh5_free(wps->dh_ctx);
82 wps->dh_ctx = NULL;
83 dh_shared = wpabuf_zeropad(dh_shared, 192);
84 if (dh_shared == NULL) {
85 wpa_printf(MSG_DEBUG, "WPS: Failed to derive DH shared key");
86 return -1;
87 }
88
89 /* Own DH private key is not needed anymore */
90 wpabuf_free(wps->dh_privkey);
91 wps->dh_privkey = NULL;
92
93 wpa_hexdump_buf_key(MSG_DEBUG, "WPS: DH shared key", dh_shared);
94
95 /* DHKey = SHA-256(g^AB mod p) */
96 addr[0] = wpabuf_head(dh_shared);
97 len[0] = wpabuf_len(dh_shared);
98 sha256_vector(1, addr, len, dhkey);
99 wpa_hexdump_key(MSG_DEBUG, "WPS: DHKey", dhkey, sizeof(dhkey));
100 wpabuf_free(dh_shared);
101
102 /* KDK = HMAC-SHA-256_DHKey(N1 || EnrolleeMAC || N2) */
103 addr[0] = wps->nonce_e;
104 len[0] = WPS_NONCE_LEN;
105 addr[1] = wps->mac_addr_e;
106 len[1] = ETH_ALEN;
107 addr[2] = wps->nonce_r;
108 len[2] = WPS_NONCE_LEN;
109 hmac_sha256_vector(dhkey, sizeof(dhkey), 3, addr, len, kdk);
110 wpa_hexdump_key(MSG_DEBUG, "WPS: KDK", kdk, sizeof(kdk));
111
112 wps_kdf(kdk, NULL, 0, "Wi-Fi Easy and Secure Key Derivation",
113 keys, sizeof(keys));
114 os_memcpy(wps->authkey, keys, WPS_AUTHKEY_LEN);
115 os_memcpy(wps->keywrapkey, keys + WPS_AUTHKEY_LEN, WPS_KEYWRAPKEY_LEN);
116 os_memcpy(wps->emsk, keys + WPS_AUTHKEY_LEN + WPS_KEYWRAPKEY_LEN,
117 WPS_EMSK_LEN);
118
119 wpa_hexdump_key(MSG_DEBUG, "WPS: AuthKey",
120 wps->authkey, WPS_AUTHKEY_LEN);
121 wpa_hexdump_key(MSG_DEBUG, "WPS: KeyWrapKey",
122 wps->keywrapkey, WPS_KEYWRAPKEY_LEN);
123 wpa_hexdump_key(MSG_DEBUG, "WPS: EMSK", wps->emsk, WPS_EMSK_LEN);
124
125 return 0;
126 }
127
128
wps_derive_psk(struct wps_data * wps,const u8 * dev_passwd,size_t dev_passwd_len)129 void wps_derive_psk(struct wps_data *wps, const u8 *dev_passwd,
130 size_t dev_passwd_len)
131 {
132 u8 hash[SHA256_MAC_LEN];
133
134 hmac_sha256(wps->authkey, WPS_AUTHKEY_LEN, dev_passwd,
135 (dev_passwd_len + 1) / 2, hash);
136 os_memcpy(wps->psk1, hash, WPS_PSK_LEN);
137 hmac_sha256(wps->authkey, WPS_AUTHKEY_LEN,
138 dev_passwd + (dev_passwd_len + 1) / 2,
139 dev_passwd_len / 2, hash);
140 os_memcpy(wps->psk2, hash, WPS_PSK_LEN);
141
142 wpa_hexdump_ascii_key(MSG_DEBUG, "WPS: Device Password",
143 dev_passwd, dev_passwd_len);
144 wpa_hexdump_key(MSG_DEBUG, "WPS: PSK1", wps->psk1, WPS_PSK_LEN);
145 wpa_hexdump_key(MSG_DEBUG, "WPS: PSK2", wps->psk2, WPS_PSK_LEN);
146 }
147
148
wps_decrypt_encr_settings(struct wps_data * wps,const u8 * encr,size_t encr_len)149 struct wpabuf * wps_decrypt_encr_settings(struct wps_data *wps, const u8 *encr,
150 size_t encr_len)
151 {
152 struct wpabuf *decrypted;
153 const size_t block_size = 16;
154 size_t i;
155 u8 pad;
156 const u8 *pos;
157
158 /* AES-128-CBC */
159 if (encr == NULL || encr_len < 2 * block_size || encr_len % block_size)
160 {
161 wpa_printf(MSG_DEBUG, "WPS: No Encrypted Settings received");
162 return NULL;
163 }
164
165 decrypted = wpabuf_alloc(encr_len - block_size);
166 if (decrypted == NULL)
167 return NULL;
168
169 wpa_hexdump(MSG_MSGDUMP, "WPS: Encrypted Settings", encr, encr_len);
170 wpabuf_put_data(decrypted, encr + block_size, encr_len - block_size);
171 if (aes_128_cbc_decrypt(wps->keywrapkey, encr, wpabuf_mhead(decrypted),
172 wpabuf_len(decrypted))) {
173 wpabuf_free(decrypted);
174 return NULL;
175 }
176
177 wpa_hexdump_buf_key(MSG_MSGDUMP, "WPS: Decrypted Encrypted Settings",
178 decrypted);
179
180 pos = wpabuf_head_u8(decrypted) + wpabuf_len(decrypted) - 1;
181 pad = *pos;
182 if (pad > wpabuf_len(decrypted)) {
183 wpa_printf(MSG_DEBUG, "WPS: Invalid PKCS#5 v2.0 pad value");
184 wpabuf_free(decrypted);
185 return NULL;
186 }
187 for (i = 0; i < pad; i++) {
188 if (*pos-- != pad) {
189 wpa_printf(MSG_DEBUG, "WPS: Invalid PKCS#5 v2.0 pad "
190 "string");
191 wpabuf_free(decrypted);
192 return NULL;
193 }
194 }
195 decrypted->used -= pad;
196
197 return decrypted;
198 }
199
200
201 /**
202 * wps_pin_checksum - Compute PIN checksum
203 * @pin: Seven digit PIN (i.e., eight digit PIN without the checksum digit)
204 * Returns: Checksum digit
205 */
wps_pin_checksum(unsigned int pin)206 unsigned int wps_pin_checksum(unsigned int pin)
207 {
208 unsigned int accum = 0;
209 while (pin) {
210 accum += 3 * (pin % 10);
211 pin /= 10;
212 accum += pin % 10;
213 pin /= 10;
214 }
215
216 return (10 - accum % 10) % 10;
217 }
218
219
220 /**
221 * wps_pin_valid - Check whether a PIN has a valid checksum
222 * @pin: Eight digit PIN (i.e., including the checksum digit)
223 * Returns: 1 if checksum digit is valid, or 0 if not
224 */
wps_pin_valid(unsigned int pin)225 unsigned int wps_pin_valid(unsigned int pin)
226 {
227 return wps_pin_checksum(pin / 10) == (pin % 10);
228 }
229
230
231 /**
232 * wps_generate_pin - Generate a random PIN
233 * Returns: Eight digit PIN (i.e., including the checksum digit)
234 */
wps_generate_pin(void)235 unsigned int wps_generate_pin(void)
236 {
237 unsigned int val;
238
239 /* Generate seven random digits for the PIN */
240 if (random_get_bytes((unsigned char *) &val, sizeof(val)) < 0) {
241 struct os_time now;
242 os_get_time(&now);
243 val = os_random() ^ now.sec ^ now.usec;
244 }
245 val %= 10000000;
246
247 /* Append checksum digit */
248 return val * 10 + wps_pin_checksum(val);
249 }
250
251
wps_pin_str_valid(const char * pin)252 int wps_pin_str_valid(const char *pin)
253 {
254 const char *p;
255 size_t len;
256
257 p = pin;
258 while (*p >= '0' && *p <= '9')
259 p++;
260 if (*p != '\0')
261 return 0;
262
263 len = p - pin;
264 return len == 4 || len == 8;
265 }
266
267
wps_fail_event(struct wps_context * wps,enum wps_msg_type msg,u16 config_error,u16 error_indication,const u8 * mac_addr)268 void wps_fail_event(struct wps_context *wps, enum wps_msg_type msg,
269 u16 config_error, u16 error_indication, const u8 *mac_addr)
270 {
271 union wps_event_data data;
272
273 if (wps->event_cb == NULL)
274 return;
275
276 os_memset(&data, 0, sizeof(data));
277 data.fail.msg = msg;
278 data.fail.config_error = config_error;
279 data.fail.error_indication = error_indication;
280 os_memcpy(data.fail.peer_macaddr, mac_addr, ETH_ALEN);
281 wps->event_cb(wps->cb_ctx, WPS_EV_FAIL, &data);
282 }
283
284
wps_success_event(struct wps_context * wps,const u8 * mac_addr)285 void wps_success_event(struct wps_context *wps, const u8 *mac_addr)
286 {
287 union wps_event_data data;
288
289 if (wps->event_cb == NULL)
290 return;
291
292 os_memset(&data, 0, sizeof(data));
293 os_memcpy(data.success.peer_macaddr, mac_addr, ETH_ALEN);
294 wps->event_cb(wps->cb_ctx, WPS_EV_SUCCESS, &data);
295 }
296
297
wps_pwd_auth_fail_event(struct wps_context * wps,int enrollee,int part,const u8 * mac_addr)298 void wps_pwd_auth_fail_event(struct wps_context *wps, int enrollee, int part,
299 const u8 *mac_addr)
300 {
301 union wps_event_data data;
302
303 if (wps->event_cb == NULL)
304 return;
305
306 os_memset(&data, 0, sizeof(data));
307 data.pwd_auth_fail.enrollee = enrollee;
308 data.pwd_auth_fail.part = part;
309 os_memcpy(data.pwd_auth_fail.peer_macaddr, mac_addr, ETH_ALEN);
310 wps->event_cb(wps->cb_ctx, WPS_EV_PWD_AUTH_FAIL, &data);
311 }
312
313
wps_pbc_overlap_event(struct wps_context * wps)314 void wps_pbc_overlap_event(struct wps_context *wps)
315 {
316 if (wps->event_cb == NULL)
317 return;
318
319 wps->event_cb(wps->cb_ctx, WPS_EV_PBC_OVERLAP, NULL);
320 }
321
322
wps_pbc_timeout_event(struct wps_context * wps)323 void wps_pbc_timeout_event(struct wps_context *wps)
324 {
325 if (wps->event_cb == NULL)
326 return;
327
328 wps->event_cb(wps->cb_ctx, WPS_EV_PBC_TIMEOUT, NULL);
329 }
330
331
wps_pbc_active_event(struct wps_context * wps)332 void wps_pbc_active_event(struct wps_context *wps)
333 {
334 if (wps->event_cb == NULL)
335 return;
336
337 wps->event_cb(wps->cb_ctx, WPS_EV_PBC_ACTIVE, NULL);
338 }
339
340
wps_pbc_disable_event(struct wps_context * wps)341 void wps_pbc_disable_event(struct wps_context *wps)
342 {
343 if (wps->event_cb == NULL)
344 return;
345
346 wps->event_cb(wps->cb_ctx, WPS_EV_PBC_DISABLE, NULL);
347 }
348
349
350 #ifdef CONFIG_WPS_OOB
351
wps_get_oob_cred(struct wps_context * wps)352 struct wpabuf * wps_get_oob_cred(struct wps_context *wps)
353 {
354 struct wps_data data;
355 struct wpabuf *plain;
356
357 plain = wpabuf_alloc(500);
358 if (plain == NULL) {
359 wpa_printf(MSG_ERROR, "WPS: Failed to allocate memory for OOB "
360 "credential");
361 return NULL;
362 }
363
364 os_memset(&data, 0, sizeof(data));
365 data.wps = wps;
366 data.auth_type = wps->auth_types;
367 data.encr_type = wps->encr_types;
368 if (wps_build_version(plain) ||
369 wps_build_cred(&data, plain) ||
370 wps_build_wfa_ext(plain, 0, NULL, 0)) {
371 os_free(data.new_psk);
372 wpabuf_free(plain);
373 return NULL;
374 }
375
376 if (wps->wps_state == WPS_STATE_NOT_CONFIGURED && data.new_psk &&
377 wps->ap) {
378 struct wps_credential cred;
379
380 wpa_printf(MSG_DEBUG, "WPS: Moving to Configured state based "
381 "on credential token generation");
382
383 os_memset(&cred, 0, sizeof(cred));
384 os_memcpy(cred.ssid, wps->ssid, wps->ssid_len);
385 cred.ssid_len = wps->ssid_len;
386 cred.auth_type = WPS_AUTH_WPAPSK | WPS_AUTH_WPA2PSK;
387 cred.encr_type = WPS_ENCR_TKIP | WPS_ENCR_AES;
388 os_memcpy(cred.key, data.new_psk, data.new_psk_len);
389 cred.key_len = data.new_psk_len;
390
391 wps->wps_state = WPS_STATE_CONFIGURED;
392 wpa_hexdump_ascii_key(MSG_DEBUG,
393 "WPS: Generated random passphrase",
394 data.new_psk, data.new_psk_len);
395 if (wps->cred_cb)
396 wps->cred_cb(wps->cb_ctx, &cred);
397 }
398
399 os_free(data.new_psk);
400
401 return plain;
402 }
403
404
wps_build_nfc_pw_token(u16 dev_pw_id,const struct wpabuf * pubkey,const struct wpabuf * dev_pw)405 struct wpabuf * wps_build_nfc_pw_token(u16 dev_pw_id,
406 const struct wpabuf *pubkey,
407 const struct wpabuf *dev_pw)
408 {
409 struct wpabuf *data;
410
411 data = wpabuf_alloc(200);
412 if (data == NULL)
413 return NULL;
414
415 if (wps_build_version(data) ||
416 wps_build_oob_dev_pw(data, dev_pw_id, pubkey,
417 wpabuf_head(dev_pw), wpabuf_len(dev_pw)) ||
418 wps_build_wfa_ext(data, 0, NULL, 0)) {
419 wpa_printf(MSG_ERROR, "WPS: Failed to build NFC password "
420 "token");
421 wpabuf_free(data);
422 return NULL;
423 }
424
425 return data;
426 }
427
428
wps_oob_use_cred(struct wps_context * wps,struct wps_parse_attr * attr)429 int wps_oob_use_cred(struct wps_context *wps, struct wps_parse_attr *attr)
430 {
431 struct wpabuf msg;
432 size_t i;
433
434 for (i = 0; i < attr->num_cred; i++) {
435 struct wps_credential local_cred;
436 struct wps_parse_attr cattr;
437
438 os_memset(&local_cred, 0, sizeof(local_cred));
439 wpabuf_set(&msg, attr->cred[i], attr->cred_len[i]);
440 if (wps_parse_msg(&msg, &cattr) < 0 ||
441 wps_process_cred(&cattr, &local_cred)) {
442 wpa_printf(MSG_ERROR, "WPS: Failed to parse OOB "
443 "credential");
444 return -1;
445 }
446 wps->cred_cb(wps->cb_ctx, &local_cred);
447 }
448
449 return 0;
450 }
451
452
453 #endif /* CONFIG_WPS_OOB */
454
455
wps_dev_type_str2bin(const char * str,u8 dev_type[WPS_DEV_TYPE_LEN])456 int wps_dev_type_str2bin(const char *str, u8 dev_type[WPS_DEV_TYPE_LEN])
457 {
458 const char *pos;
459
460 /* <categ>-<OUI>-<subcateg> */
461 WPA_PUT_BE16(dev_type, atoi(str));
462 pos = os_strchr(str, '-');
463 if (pos == NULL)
464 return -1;
465 pos++;
466 if (hexstr2bin(pos, &dev_type[2], 4))
467 return -1;
468 pos = os_strchr(pos, '-');
469 if (pos == NULL)
470 return -1;
471 pos++;
472 WPA_PUT_BE16(&dev_type[6], atoi(pos));
473
474
475 return 0;
476 }
477
478
wps_dev_type_bin2str(const u8 dev_type[WPS_DEV_TYPE_LEN],char * buf,size_t buf_len)479 char * wps_dev_type_bin2str(const u8 dev_type[WPS_DEV_TYPE_LEN], char *buf,
480 size_t buf_len)
481 {
482 int ret;
483
484 ret = os_snprintf(buf, buf_len, "%u-%08X-%u",
485 WPA_GET_BE16(dev_type), WPA_GET_BE32(&dev_type[2]),
486 WPA_GET_BE16(&dev_type[6]));
487 if (ret < 0 || (unsigned int) ret >= buf_len)
488 return NULL;
489
490 return buf;
491 }
492
493
uuid_gen_mac_addr(const u8 * mac_addr,u8 * uuid)494 void uuid_gen_mac_addr(const u8 *mac_addr, u8 *uuid)
495 {
496 const u8 *addr[2];
497 size_t len[2];
498 u8 hash[SHA1_MAC_LEN];
499 u8 nsid[16] = {
500 0x52, 0x64, 0x80, 0xf8,
501 0xc9, 0x9b,
502 0x4b, 0xe5,
503 0xa6, 0x55,
504 0x58, 0xed, 0x5f, 0x5d, 0x60, 0x84
505 };
506
507 addr[0] = nsid;
508 len[0] = sizeof(nsid);
509 addr[1] = mac_addr;
510 len[1] = 6;
511 sha1_vector(2, addr, len, hash);
512 os_memcpy(uuid, hash, 16);
513
514 /* Version: 5 = named-based version using SHA-1 */
515 uuid[6] = (5 << 4) | (uuid[6] & 0x0f);
516
517 /* Variant specified in RFC 4122 */
518 uuid[8] = 0x80 | (uuid[8] & 0x3f);
519 }
520
521
wps_config_methods_str2bin(const char * str)522 u16 wps_config_methods_str2bin(const char *str)
523 {
524 u16 methods = 0;
525
526 if (str == NULL) {
527 /* Default to enabling methods based on build configuration */
528 methods |= WPS_CONFIG_DISPLAY | WPS_CONFIG_KEYPAD;
529 #ifdef CONFIG_WPS2
530 methods |= WPS_CONFIG_VIRT_DISPLAY;
531 #endif /* CONFIG_WPS2 */
532 #ifdef CONFIG_WPS_NFC
533 methods |= WPS_CONFIG_NFC_INTERFACE;
534 #endif /* CONFIG_WPS_NFC */
535 } else {
536 if (os_strstr(str, "ethernet"))
537 methods |= WPS_CONFIG_ETHERNET;
538 if (os_strstr(str, "label"))
539 methods |= WPS_CONFIG_LABEL;
540 if (os_strstr(str, "display"))
541 methods |= WPS_CONFIG_DISPLAY;
542 if (os_strstr(str, "ext_nfc_token"))
543 methods |= WPS_CONFIG_EXT_NFC_TOKEN;
544 if (os_strstr(str, "int_nfc_token"))
545 methods |= WPS_CONFIG_INT_NFC_TOKEN;
546 if (os_strstr(str, "nfc_interface"))
547 methods |= WPS_CONFIG_NFC_INTERFACE;
548 if (os_strstr(str, "push_button"))
549 methods |= WPS_CONFIG_PUSHBUTTON;
550 if (os_strstr(str, "keypad"))
551 methods |= WPS_CONFIG_KEYPAD;
552 #ifdef CONFIG_WPS2
553 if (os_strstr(str, "virtual_display"))
554 methods |= WPS_CONFIG_VIRT_DISPLAY;
555 if (os_strstr(str, "physical_display"))
556 methods |= WPS_CONFIG_PHY_DISPLAY;
557 if (os_strstr(str, "virtual_push_button"))
558 methods |= WPS_CONFIG_VIRT_PUSHBUTTON;
559 if (os_strstr(str, "physical_push_button"))
560 methods |= WPS_CONFIG_PHY_PUSHBUTTON;
561 #endif /* CONFIG_WPS2 */
562 }
563
564 return methods;
565 }
566
567
wps_build_wsc_ack(struct wps_data * wps)568 struct wpabuf * wps_build_wsc_ack(struct wps_data *wps)
569 {
570 struct wpabuf *msg;
571
572 wpa_printf(MSG_DEBUG, "WPS: Building Message WSC_ACK");
573
574 msg = wpabuf_alloc(1000);
575 if (msg == NULL)
576 return NULL;
577
578 if (wps_build_version(msg) ||
579 wps_build_msg_type(msg, WPS_WSC_ACK) ||
580 wps_build_enrollee_nonce(wps, msg) ||
581 wps_build_registrar_nonce(wps, msg) ||
582 wps_build_wfa_ext(msg, 0, NULL, 0)) {
583 wpabuf_free(msg);
584 return NULL;
585 }
586
587 return msg;
588 }
589
590
wps_build_wsc_nack(struct wps_data * wps)591 struct wpabuf * wps_build_wsc_nack(struct wps_data *wps)
592 {
593 struct wpabuf *msg;
594
595 wpa_printf(MSG_DEBUG, "WPS: Building Message WSC_NACK");
596
597 msg = wpabuf_alloc(1000);
598 if (msg == NULL)
599 return NULL;
600
601 if (wps_build_version(msg) ||
602 wps_build_msg_type(msg, WPS_WSC_NACK) ||
603 wps_build_enrollee_nonce(wps, msg) ||
604 wps_build_registrar_nonce(wps, msg) ||
605 wps_build_config_error(msg, wps->config_error) ||
606 wps_build_wfa_ext(msg, 0, NULL, 0)) {
607 wpabuf_free(msg);
608 return NULL;
609 }
610
611 return msg;
612 }
613
614
615 #ifdef CONFIG_WPS_NFC
616
wps_nfc_token_build(int ndef,int id,struct wpabuf * pubkey,struct wpabuf * dev_pw)617 struct wpabuf * wps_nfc_token_build(int ndef, int id, struct wpabuf *pubkey,
618 struct wpabuf *dev_pw)
619 {
620 struct wpabuf *ret;
621
622 if (pubkey == NULL || dev_pw == NULL)
623 return NULL;
624
625 ret = wps_build_nfc_pw_token(id, pubkey, dev_pw);
626 if (ndef && ret) {
627 struct wpabuf *tmp;
628 tmp = ndef_build_wifi(ret);
629 wpabuf_free(ret);
630 if (tmp == NULL)
631 return NULL;
632 ret = tmp;
633 }
634
635 return ret;
636 }
637
638
wps_nfc_token_gen(int ndef,int * id,struct wpabuf ** pubkey,struct wpabuf ** privkey,struct wpabuf ** dev_pw)639 struct wpabuf * wps_nfc_token_gen(int ndef, int *id, struct wpabuf **pubkey,
640 struct wpabuf **privkey,
641 struct wpabuf **dev_pw)
642 {
643 struct wpabuf *priv = NULL, *pub = NULL, *pw;
644 void *dh_ctx;
645 u16 val;
646
647 pw = wpabuf_alloc(WPS_OOB_DEVICE_PASSWORD_LEN);
648 if (pw == NULL)
649 return NULL;
650
651 if (random_get_bytes(wpabuf_put(pw, WPS_OOB_DEVICE_PASSWORD_LEN),
652 WPS_OOB_DEVICE_PASSWORD_LEN) ||
653 random_get_bytes((u8 *) &val, sizeof(val))) {
654 wpabuf_free(pw);
655 return NULL;
656 }
657
658 dh_ctx = dh5_init(&priv, &pub);
659 if (dh_ctx == NULL) {
660 wpabuf_free(pw);
661 return NULL;
662 }
663 dh5_free(dh_ctx);
664
665 *id = 0x10 + val % 0xfff0;
666 wpabuf_free(*pubkey);
667 *pubkey = pub;
668 wpabuf_free(*privkey);
669 *privkey = priv;
670 wpabuf_free(*dev_pw);
671 *dev_pw = pw;
672
673 return wps_nfc_token_build(ndef, *id, *pubkey, *dev_pw);
674 }
675
676 #endif /* CONFIG_WPS_NFC */
677