libeap/src/wps/wps_common.c

   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
  24 void 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
  62 int 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
 132 int 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
 155 struct 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  */
 212 unsigned 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  */
 231 unsigned 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  */
 241 int 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
 256 int 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
 272 void 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
 289 void 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
 302 void 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
 318 void 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
 327 void 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
 336 void 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
 345 void 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
 356 struct 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
 412 struct 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
 435 int 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
 462 int 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
 485 char * 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
 500 void 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
 528 u16 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
 575 struct 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
 598 struct 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
 624 struct 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
 646 int 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
 671 struct 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
 702 struct 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
 739 static 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
 751 static 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
 782 struct 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
 822 struct 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
 859 struct 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 */