src/eap_server/eap_server_aka.c

   1 /*
   2  * hostapd / EAP-AKA (RFC 4187) and EAP-AKA' (RFC 5448)
   3  * Copyright (c) 2005-2012, 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/sha256.h"
  13 #include "crypto/crypto.h"
  14 #include "crypto/random.h"
  15 #include "eap_common/eap_sim_common.h"
  16 #include "eap_server/eap_i.h"
  17 #include "eap_server/eap_sim_db.h"
  18
  19
  20 struct eap_aka_data {
  21         u8 mk[EAP_SIM_MK_LEN];
  22         u8 nonce_s[EAP_SIM_NONCE_S_LEN];
  23         u8 k_aut[EAP_AKA_PRIME_K_AUT_LEN];
  24         u8 k_encr[EAP_SIM_K_ENCR_LEN];
  25         u8 k_re[EAP_AKA_PRIME_K_RE_LEN]; /* EAP-AKA' only */
  26         u8 msk[EAP_SIM_KEYING_DATA_LEN];
  27         u8 emsk[EAP_EMSK_LEN];
  28         u8 rand[EAP_AKA_RAND_LEN];
  29         u8 autn[EAP_AKA_AUTN_LEN];
  30         u8 ck[EAP_AKA_CK_LEN];
  31         u8 ik[EAP_AKA_IK_LEN];
  32         u8 res[EAP_AKA_RES_MAX_LEN];
  33         size_t res_len;
  34         enum {
  35                 IDENTITY, CHALLENGE, REAUTH, NOTIFICATION, SUCCESS, FAILURE
  36         } state;
  37         char *next_pseudonym;
  38         char *next_reauth_id;
  39         u16 counter;
  40         struct eap_sim_reauth *reauth;
  41         int auts_reported; /* whether the current AUTS has been reported to the
  42                             * eap_sim_db */
  43         u16 notification;
  44         int use_result_ind;
  45
  46         struct wpabuf *id_msgs;
  47         int pending_id;
  48         u8 eap_method;
  49         u8 *network_name;
  50         size_t network_name_len;
  51         u16 kdf;
  52         int identity_round;
  53         char permanent[20]; /* Permanent username */
  54 };
  55
  56
  57 static void eap_aka_fullauth(struct eap_sm *sm, struct eap_aka_data *data);
  58
  59
  60 static const char * eap_aka_state_txt(int state)
  61 {
  62         switch (state) {
  63         case IDENTITY:
  64                 return "IDENTITY";
  65         case CHALLENGE:
  66                 return "CHALLENGE";
  67         case REAUTH:
  68                 return "REAUTH";
  69         case SUCCESS:
  70                 return "SUCCESS";
  71         case FAILURE:
  72                 return "FAILURE";
  73         case NOTIFICATION:
  74                 return "NOTIFICATION";
  75         default:
  76                 return "Unknown?!";
  77         }
  78 }
  79
  80
  81 static void eap_aka_state(struct eap_aka_data *data, int state)
  82 {
  83         wpa_printf(MSG_DEBUG, "EAP-AKA: %s -> %s",
  84                    eap_aka_state_txt(data->state),
  85                    eap_aka_state_txt(state));
  86         data->state = state;
  87 }
  88
  89
  90 static int eap_aka_check_identity_reauth(struct eap_sm *sm,
  91                                          struct eap_aka_data *data,
  92                                          const char *username)
  93 {
  94         if (data->eap_method == EAP_TYPE_AKA_PRIME &&
  95             username[0] != EAP_AKA_PRIME_REAUTH_ID_PREFIX)
  96                 return 0;
  97         if (data->eap_method == EAP_TYPE_AKA &&
  98             username[0] != EAP_AKA_REAUTH_ID_PREFIX)
  99                 return 0;
 100
 101         wpa_printf(MSG_DEBUG, "EAP-AKA: Reauth username '%s'", username);
 102         data->reauth = eap_sim_db_get_reauth_entry(sm->eap_sim_db_priv,
 103                                                    username);
 104         if (data->reauth == NULL) {
 105                 wpa_printf(MSG_DEBUG, "EAP-AKA: Unknown reauth identity - "
 106                            "request full auth identity");
 107                 /* Remain in IDENTITY state for another round */
 108                 return 0;
 109         }
 110
 111         wpa_printf(MSG_DEBUG, "EAP-AKA: Using fast re-authentication");
 112         os_strlcpy(data->permanent, data->reauth->permanent,
 113                    sizeof(data->permanent));
 114         data->counter = data->reauth->counter;
 115         if (data->eap_method == EAP_TYPE_AKA_PRIME) {
 116                 os_memcpy(data->k_encr, data->reauth->k_encr,
 117                           EAP_SIM_K_ENCR_LEN);
 118                 os_memcpy(data->k_aut, data->reauth->k_aut,
 119                           EAP_AKA_PRIME_K_AUT_LEN);
 120                 os_memcpy(data->k_re, data->reauth->k_re,
 121                           EAP_AKA_PRIME_K_RE_LEN);
 122         } else {
 123                 os_memcpy(data->mk, data->reauth->mk, EAP_SIM_MK_LEN);
 124         }
 125
 126         eap_aka_state(data, REAUTH);
 127         return 1;
 128 }
 129
 130
 131 static void eap_aka_check_identity(struct eap_sm *sm,
 132                                    struct eap_aka_data *data)
 133 {
 134         char *username;
 135
 136         /* Check if we already know the identity from EAP-Response/Identity */
 137
 138         username = sim_get_username(sm->identity, sm->identity_len);
 139         if (username == NULL)
 140                 return;
 141
 142         if (eap_aka_check_identity_reauth(sm, data, username) > 0) {
 143                 os_free(username);
 144                 /*
 145                  * Since re-auth username was recognized, skip AKA/Identity
 146                  * exchange.
 147                  */
 148                 return;
 149         }
 150
 151         if ((data->eap_method == EAP_TYPE_AKA_PRIME &&
 152              username[0] == EAP_AKA_PRIME_PSEUDONYM_PREFIX) ||
 153             (data->eap_method == EAP_TYPE_AKA &&
 154              username[0] == EAP_AKA_PSEUDONYM_PREFIX)) {
 155                 const char *permanent;
 156                 wpa_printf(MSG_DEBUG, "EAP-AKA: Pseudonym username '%s'",
 157                            username);
 158                 permanent = eap_sim_db_get_permanent(
 159                         sm->eap_sim_db_priv, username);
 160                 if (permanent == NULL) {
 161                         os_free(username);
 162                         wpa_printf(MSG_DEBUG, "EAP-AKA: Unknown pseudonym "
 163                                    "identity - request permanent identity");
 164                         /* Remain in IDENTITY state for another round */
 165                         return;
 166                 }
 167                 os_strlcpy(data->permanent, permanent,
 168                            sizeof(data->permanent));
 169                 /*
 170                  * Since pseudonym username was recognized, skip AKA/Identity
 171                  * exchange.
 172                  */
 173                 eap_aka_fullauth(sm, data);
 174         }
 175
 176         os_free(username);
 177 }
 178
 179
 180 static void * eap_aka_init(struct eap_sm *sm)
 181 {
 182         struct eap_aka_data *data;
 183
 184         if (sm->eap_sim_db_priv == NULL) {
 185                 wpa_printf(MSG_WARNING, "EAP-AKA: eap_sim_db not configured");
 186                 return NULL;
 187         }
 188
 189         data = os_zalloc(sizeof(*data));
 190         if (data == NULL)
 191                 return NULL;
 192
 193         data->eap_method = EAP_TYPE_AKA;
 194
 195         data->state = IDENTITY;
 196         data->pending_id = -1;
 197         eap_aka_check_identity(sm, data);
 198
 199         return data;
 200 }
 201
 202
 203 #ifdef EAP_SERVER_AKA_PRIME
 204 static void * eap_aka_prime_init(struct eap_sm *sm)
 205 {
 206         struct eap_aka_data *data;
 207         /* TODO: make ANID configurable; see 3GPP TS 24.302 */
 208         char *network_name = "WLAN";
 209
 210         if (sm->eap_sim_db_priv == NULL) {
 211                 wpa_printf(MSG_WARNING, "EAP-AKA: eap_sim_db not configured");
 212                 return NULL;
 213         }
 214
 215         data = os_zalloc(sizeof(*data));
 216         if (data == NULL)
 217                 return NULL;
 218
 219         data->eap_method = EAP_TYPE_AKA_PRIME;
 220         data->network_name = (u8 *) os_strdup(network_name);
 221         if (data->network_name == NULL) {
 222                 os_free(data);
 223                 return NULL;
 224         }
 225
 226         data->network_name_len = os_strlen(network_name);
 227
 228         data->state = IDENTITY;
 229         data->pending_id = -1;
 230         eap_aka_check_identity(sm, data);
 231
 232         return data;
 233 }
 234 #endif /* EAP_SERVER_AKA_PRIME */
 235
 236
 237 static void eap_aka_reset(struct eap_sm *sm, void *priv)
 238 {
 239         struct eap_aka_data *data = priv;
 240         os_free(data->next_pseudonym);
 241         os_free(data->next_reauth_id);
 242         wpabuf_free(data->id_msgs);
 243         os_free(data->network_name);
 244         bin_clear_free(data, sizeof(*data));
 245 }
 246
 247
 248 static int eap_aka_add_id_msg(struct eap_aka_data *data,
 249                               const struct wpabuf *msg)
 250 {
 251         if (msg == NULL)
 252                 return -1;
 253
 254         if (data->id_msgs == NULL) {
 255                 data->id_msgs = wpabuf_dup(msg);
 256                 return data->id_msgs == NULL ? -1 : 0;
 257         }
 258
 259         if (wpabuf_resize(&data->id_msgs, wpabuf_len(msg)) < 0)
 260                 return -1;
 261         wpabuf_put_buf(data->id_msgs, msg);
 262
 263         return 0;
 264 }
 265
 266
 267 static void eap_aka_add_checkcode(struct eap_aka_data *data,
 268                                   struct eap_sim_msg *msg)
 269 {
 270         const u8 *addr;
 271         size_t len;
 272         u8 hash[SHA256_MAC_LEN];
 273
 274         wpa_printf(MSG_DEBUG, "   AT_CHECKCODE");
 275
 276         if (data->id_msgs == NULL) {
 277                 /*
 278                  * No EAP-AKA/Identity packets were exchanged - send empty
 279                  * checkcode.
 280                  */
 281                 eap_sim_msg_add(msg, EAP_SIM_AT_CHECKCODE, 0, NULL, 0);
 282                 return;
 283         }
 284
 285         /* Checkcode is SHA1 hash over all EAP-AKA/Identity packets. */
 286         addr = wpabuf_head(data->id_msgs);
 287         len = wpabuf_len(data->id_msgs);
 288         wpa_hexdump(MSG_MSGDUMP, "EAP-AKA: AT_CHECKCODE data", addr, len);
 289         if (data->eap_method == EAP_TYPE_AKA_PRIME)
 290                 sha256_vector(1, &addr, &len, hash);
 291         else
 292                 sha1_vector(1, &addr, &len, hash);
 293
 294         eap_sim_msg_add(msg, EAP_SIM_AT_CHECKCODE, 0, hash,
 295                         data->eap_method == EAP_TYPE_AKA_PRIME ?
 296                         EAP_AKA_PRIME_CHECKCODE_LEN : EAP_AKA_CHECKCODE_LEN);
 297 }
 298
 299
 300 static int eap_aka_verify_checkcode(struct eap_aka_data *data,
 301                                     const u8 *checkcode, size_t checkcode_len)
 302 {
 303         const u8 *addr;
 304         size_t len;
 305         u8 hash[SHA256_MAC_LEN];
 306         size_t hash_len;
 307
 308         if (checkcode == NULL)
 309                 return -1;
 310
 311         if (data->id_msgs == NULL) {
 312                 if (checkcode_len != 0) {
 313                         wpa_printf(MSG_DEBUG, "EAP-AKA: Checkcode from peer "
 314                                    "indicates that AKA/Identity messages were "
 315                                    "used, but they were not");
 316                         return -1;
 317                 }
 318                 return 0;
 319         }
 320
 321         hash_len = data->eap_method == EAP_TYPE_AKA_PRIME ?
 322                 EAP_AKA_PRIME_CHECKCODE_LEN : EAP_AKA_CHECKCODE_LEN;
 323
 324         if (checkcode_len != hash_len) {
 325                 wpa_printf(MSG_DEBUG, "EAP-AKA: Checkcode from peer indicates "
 326                            "that AKA/Identity message were not used, but they "
 327                            "were");
 328                 return -1;
 329         }
 330
 331         /* Checkcode is SHA1 hash over all EAP-AKA/Identity packets. */
 332         addr = wpabuf_head(data->id_msgs);
 333         len = wpabuf_len(data->id_msgs);
 334         if (data->eap_method == EAP_TYPE_AKA_PRIME)
 335                 sha256_vector(1, &addr, &len, hash);
 336         else
 337                 sha1_vector(1, &addr, &len, hash);
 338
 339         if (os_memcmp_const(hash, checkcode, hash_len) != 0) {
 340                 wpa_printf(MSG_DEBUG, "EAP-AKA: Mismatch in AT_CHECKCODE");
 341                 return -1;
 342         }
 343
 344         return 0;
 345 }
 346
 347
 348 static struct wpabuf * eap_aka_build_identity(struct eap_sm *sm,
 349                                               struct eap_aka_data *data, u8 id)
 350 {
 351         struct eap_sim_msg *msg;
 352         struct wpabuf *buf;
 353
 354         wpa_printf(MSG_DEBUG, "EAP-AKA: Generating Identity");
 355         msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, data->eap_method,
 356                                EAP_AKA_SUBTYPE_IDENTITY);
 357         data->identity_round++;
 358         if (data->identity_round == 1) {
 359                 /*
 360                  * RFC 4187, Chap. 4.1.4 recommends that identity from EAP is
 361                  * ignored and the AKA/Identity is used to request the
 362                  * identity.
 363                  */
 364                 wpa_printf(MSG_DEBUG, "   AT_ANY_ID_REQ");
 365                 eap_sim_msg_add(msg, EAP_SIM_AT_ANY_ID_REQ, 0, NULL, 0);
 366         } else if (data->identity_round > 3) {
 367                 /* Cannot use more than three rounds of Identity messages */
 368                 eap_sim_msg_free(msg);
 369                 return NULL;
 370         } else if (sm->identity && sm->identity_len > 0 &&
 371                    (sm->identity[0] == EAP_AKA_REAUTH_ID_PREFIX ||
 372                     sm->identity[0] == EAP_AKA_PRIME_REAUTH_ID_PREFIX)) {
 373                 /* Reauth id may have expired - try fullauth */
 374                 wpa_printf(MSG_DEBUG, "   AT_FULLAUTH_ID_REQ");
 375                 eap_sim_msg_add(msg, EAP_SIM_AT_FULLAUTH_ID_REQ, 0, NULL, 0);
 376         } else {
 377                 wpa_printf(MSG_DEBUG, "   AT_PERMANENT_ID_REQ");
 378                 eap_sim_msg_add(msg, EAP_SIM_AT_PERMANENT_ID_REQ, 0, NULL, 0);
 379         }
 380         buf = eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
 381         if (eap_aka_add_id_msg(data, buf) < 0) {
 382                 wpabuf_free(buf);
 383                 return NULL;
 384         }
 385         data->pending_id = id;
 386         return buf;
 387 }
 388
 389
 390 static int eap_aka_build_encr(struct eap_sm *sm, struct eap_aka_data *data,
 391                               struct eap_sim_msg *msg, u16 counter,
 392                               const u8 *nonce_s)
 393 {
 394         os_free(data->next_pseudonym);
 395         if (nonce_s == NULL) {
 396                 data->next_pseudonym =
 397                         eap_sim_db_get_next_pseudonym(
 398                                 sm->eap_sim_db_priv,
 399                                 data->eap_method == EAP_TYPE_AKA_PRIME ?
 400                                 EAP_SIM_DB_AKA_PRIME : EAP_SIM_DB_AKA);
 401         } else {
 402                 /* Do not update pseudonym during re-authentication */
 403                 data->next_pseudonym = NULL;
 404         }
 405         os_free(data->next_reauth_id);
 406         if (data->counter <= EAP_AKA_MAX_FAST_REAUTHS) {
 407                 data->next_reauth_id =
 408                         eap_sim_db_get_next_reauth_id(
 409                                 sm->eap_sim_db_priv,
 410                                 data->eap_method == EAP_TYPE_AKA_PRIME ?
 411                                 EAP_SIM_DB_AKA_PRIME : EAP_SIM_DB_AKA);
 412         } else {
 413                 wpa_printf(MSG_DEBUG, "EAP-AKA: Max fast re-authentication "
 414                            "count exceeded - force full authentication");
 415                 data->next_reauth_id = NULL;
 416         }
 417
 418         if (data->next_pseudonym == NULL && data->next_reauth_id == NULL &&
 419             counter == 0 && nonce_s == NULL)
 420                 return 0;
 421
 422         wpa_printf(MSG_DEBUG, "   AT_IV");
 423         wpa_printf(MSG_DEBUG, "   AT_ENCR_DATA");
 424         eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV, EAP_SIM_AT_ENCR_DATA);
 425
 426         if (counter > 0) {
 427                 wpa_printf(MSG_DEBUG, "   *AT_COUNTER (%u)", counter);
 428                 eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, counter, NULL, 0);
 429         }
 430
 431         if (nonce_s) {
 432                 wpa_printf(MSG_DEBUG, "   *AT_NONCE_S");
 433                 eap_sim_msg_add(msg, EAP_SIM_AT_NONCE_S, 0, nonce_s,
 434                                 EAP_SIM_NONCE_S_LEN);
 435         }
 436
 437         if (data->next_pseudonym) {
 438                 wpa_printf(MSG_DEBUG, "   *AT_NEXT_PSEUDONYM (%s)",
 439                            data->next_pseudonym);
 440                 eap_sim_msg_add(msg, EAP_SIM_AT_NEXT_PSEUDONYM,
 441                                 os_strlen(data->next_pseudonym),
 442                                 (u8 *) data->next_pseudonym,
 443                                 os_strlen(data->next_pseudonym));
 444         }
 445
 446         if (data->next_reauth_id) {
 447                 wpa_printf(MSG_DEBUG, "   *AT_NEXT_REAUTH_ID (%s)",
 448                            data->next_reauth_id);
 449                 eap_sim_msg_add(msg, EAP_SIM_AT_NEXT_REAUTH_ID,
 450                                 os_strlen(data->next_reauth_id),
 451                                 (u8 *) data->next_reauth_id,
 452                                 os_strlen(data->next_reauth_id));
 453         }
 454
 455         if (eap_sim_msg_add_encr_end(msg, data->k_encr, EAP_SIM_AT_PADDING)) {
 456                 wpa_printf(MSG_WARNING, "EAP-AKA: Failed to encrypt "
 457                            "AT_ENCR_DATA");
 458                 return -1;
 459         }
 460
 461         return 0;
 462 }
 463
 464
 465 static struct wpabuf * eap_aka_build_challenge(struct eap_sm *sm,
 466                                                struct eap_aka_data *data,
 467                                                u8 id)
 468 {
 469         struct eap_sim_msg *msg;
 470
 471         wpa_printf(MSG_DEBUG, "EAP-AKA: Generating Challenge");
 472         msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, data->eap_method,
 473                                EAP_AKA_SUBTYPE_CHALLENGE);
 474         wpa_printf(MSG_DEBUG, "   AT_RAND");
 475         eap_sim_msg_add(msg, EAP_SIM_AT_RAND, 0, data->rand, EAP_AKA_RAND_LEN);
 476         wpa_printf(MSG_DEBUG, "   AT_AUTN");
 477         eap_sim_msg_add(msg, EAP_SIM_AT_AUTN, 0, data->autn, EAP_AKA_AUTN_LEN);
 478         if (data->eap_method == EAP_TYPE_AKA_PRIME) {
 479                 if (data->kdf) {
 480                         /* Add the selected KDF into the beginning */
 481                         wpa_printf(MSG_DEBUG, "   AT_KDF");
 482                         eap_sim_msg_add(msg, EAP_SIM_AT_KDF, data->kdf,
 483                                         NULL, 0);
 484                 }
 485                 wpa_printf(MSG_DEBUG, "   AT_KDF");
 486                 eap_sim_msg_add(msg, EAP_SIM_AT_KDF, EAP_AKA_PRIME_KDF,
 487                                 NULL, 0);
 488                 wpa_printf(MSG_DEBUG, "   AT_KDF_INPUT");
 489                 eap_sim_msg_add(msg, EAP_SIM_AT_KDF_INPUT,
 490                                 data->network_name_len,
 491                                 data->network_name, data->network_name_len);
 492         }
 493
 494         if (eap_aka_build_encr(sm, data, msg, 0, NULL)) {
 495                 eap_sim_msg_free(msg);
 496                 return NULL;
 497         }
 498
 499         eap_aka_add_checkcode(data, msg);
 500
 501         if (sm->eap_sim_aka_result_ind) {
 502                 wpa_printf(MSG_DEBUG, "   AT_RESULT_IND");
 503                 eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
 504         }
 505
 506 #ifdef EAP_SERVER_AKA_PRIME
 507         if (data->eap_method == EAP_TYPE_AKA) {
 508                 u16 flags = 0;
 509                 int i;
 510                 int aka_prime_preferred = 0;
 511
 512                 i = 0;
 513                 while (sm->user && i < EAP_MAX_METHODS &&
 514                        (sm->user->methods[i].vendor != EAP_VENDOR_IETF ||
 515                         sm->user->methods[i].method != EAP_TYPE_NONE)) {
 516                         if (sm->user->methods[i].vendor == EAP_VENDOR_IETF) {
 517                                 if (sm->user->methods[i].method ==
 518                                     EAP_TYPE_AKA)
 519                                         break;
 520                                 if (sm->user->methods[i].method ==
 521                                     EAP_TYPE_AKA_PRIME) {
 522                                         aka_prime_preferred = 1;
 523                                         break;
 524                                 }
 525                         }
 526                         i++;
 527                 }
 528
 529                 if (aka_prime_preferred)
 530                         flags |= EAP_AKA_BIDDING_FLAG_D;
 531                 eap_sim_msg_add(msg, EAP_SIM_AT_BIDDING, flags, NULL, 0);
 532         }
 533 #endif /* EAP_SERVER_AKA_PRIME */
 534
 535         wpa_printf(MSG_DEBUG, "   AT_MAC");
 536         eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
 537         return eap_sim_msg_finish(msg, data->eap_method, data->k_aut, NULL, 0);
 538 }
 539
 540
 541 static struct wpabuf * eap_aka_build_reauth(struct eap_sm *sm,
 542                                             struct eap_aka_data *data, u8 id)
 543 {
 544         struct eap_sim_msg *msg;
 545
 546         wpa_printf(MSG_DEBUG, "EAP-AKA: Generating Re-authentication");
 547
 548         if (random_get_bytes(data->nonce_s, EAP_SIM_NONCE_S_LEN))
 549                 return NULL;
 550         wpa_hexdump_key(MSG_MSGDUMP, "EAP-AKA: NONCE_S",
 551                         data->nonce_s, EAP_SIM_NONCE_S_LEN);
 552
 553         if (data->eap_method == EAP_TYPE_AKA_PRIME) {
 554                 eap_aka_prime_derive_keys_reauth(data->k_re, data->counter,
 555                                                  sm->identity,
 556                                                  sm->identity_len,
 557                                                  data->nonce_s,
 558                                                  data->msk, data->emsk);
 559         } else {
 560                 eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut,
 561                                     data->msk, data->emsk);
 562                 eap_sim_derive_keys_reauth(data->counter, sm->identity,
 563                                            sm->identity_len, data->nonce_s,
 564                                            data->mk, data->msk, data->emsk);
 565         }
 566
 567         msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, data->eap_method,
 568                                EAP_AKA_SUBTYPE_REAUTHENTICATION);
 569
 570         if (eap_aka_build_encr(sm, data, msg, data->counter, data->nonce_s)) {
 571                 eap_sim_msg_free(msg);
 572                 return NULL;
 573         }
 574
 575         eap_aka_add_checkcode(data, msg);
 576
 577         if (sm->eap_sim_aka_result_ind) {
 578                 wpa_printf(MSG_DEBUG, "   AT_RESULT_IND");
 579                 eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
 580         }
 581
 582         wpa_printf(MSG_DEBUG, "   AT_MAC");
 583         eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
 584         return eap_sim_msg_finish(msg, data->eap_method, data->k_aut, NULL, 0);
 585 }
 586
 587
 588 static struct wpabuf * eap_aka_build_notification(struct eap_sm *sm,
 589                                                   struct eap_aka_data *data,
 590                                                   u8 id)
 591 {
 592         struct eap_sim_msg *msg;
 593
 594         wpa_printf(MSG_DEBUG, "EAP-AKA: Generating Notification");
 595         msg = eap_sim_msg_init(EAP_CODE_REQUEST, id, data->eap_method,
 596                                EAP_AKA_SUBTYPE_NOTIFICATION);
 597         wpa_printf(MSG_DEBUG, "   AT_NOTIFICATION (%d)", data->notification);
 598         eap_sim_msg_add(msg, EAP_SIM_AT_NOTIFICATION, data->notification,
 599                         NULL, 0);
 600         if (data->use_result_ind) {
 601                 if (data->reauth) {
 602                         wpa_printf(MSG_DEBUG, "   AT_IV");
 603                         wpa_printf(MSG_DEBUG, "   AT_ENCR_DATA");
 604                         eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV,
 605                                                    EAP_SIM_AT_ENCR_DATA);
 606                         wpa_printf(MSG_DEBUG, "   *AT_COUNTER (%u)",
 607                                    data->counter);
 608                         eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, data->counter,
 609                                         NULL, 0);
 610
 611                         if (eap_sim_msg_add_encr_end(msg, data->k_encr,
 612                                                      EAP_SIM_AT_PADDING)) {
 613                                 wpa_printf(MSG_WARNING, "EAP-AKA: Failed to "
 614                                            "encrypt AT_ENCR_DATA");
 615                                 eap_sim_msg_free(msg);
 616                                 return NULL;
 617                         }
 618                 }
 619
 620                 wpa_printf(MSG_DEBUG, "   AT_MAC");
 621                 eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
 622         }
 623         return eap_sim_msg_finish(msg, data->eap_method, data->k_aut, NULL, 0);
 624 }
 625
 626
 627 static struct wpabuf * eap_aka_buildReq(struct eap_sm *sm, void *priv, u8 id)
 628 {
 629         struct eap_aka_data *data = priv;
 630
 631         data->auts_reported = 0;
 632         switch (data->state) {
 633         case IDENTITY:
 634                 return eap_aka_build_identity(sm, data, id);
 635         case CHALLENGE:
 636                 return eap_aka_build_challenge(sm, data, id);
 637         case REAUTH:
 638                 return eap_aka_build_reauth(sm, data, id);
 639         case NOTIFICATION:
 640                 return eap_aka_build_notification(sm, data, id);
 641         default:
 642                 wpa_printf(MSG_DEBUG, "EAP-AKA: Unknown state %d in "
 643                            "buildReq", data->state);
 644                 break;
 645         }
 646         return NULL;
 647 }
 648
 649
 650 static Boolean eap_aka_check(struct eap_sm *sm, void *priv,
 651                              struct wpabuf *respData)
 652 {
 653         struct eap_aka_data *data = priv;
 654         const u8 *pos;
 655         size_t len;
 656
 657         pos = eap_hdr_validate(EAP_VENDOR_IETF, data->eap_method, respData,
 658                                &len);
 659         if (pos == NULL || len < 3) {
 660                 wpa_printf(MSG_INFO, "EAP-AKA: Invalid frame");
 661                 return TRUE;
 662         }
 663
 664         return FALSE;
 665 }
 666
 667
 668 static Boolean eap_aka_subtype_ok(struct eap_aka_data *data, u8 subtype)
 669 {
 670         if (subtype == EAP_AKA_SUBTYPE_CLIENT_ERROR ||
 671             subtype == EAP_AKA_SUBTYPE_AUTHENTICATION_REJECT)
 672                 return FALSE;
 673
 674         switch (data->state) {
 675         case IDENTITY:
 676                 if (subtype != EAP_AKA_SUBTYPE_IDENTITY) {
 677                         wpa_printf(MSG_INFO, "EAP-AKA: Unexpected response "
 678                                    "subtype %d", subtype);
 679                         return TRUE;
 680                 }
 681                 break;
 682         case CHALLENGE:
 683                 if (subtype != EAP_AKA_SUBTYPE_CHALLENGE &&
 684                     subtype != EAP_AKA_SUBTYPE_SYNCHRONIZATION_FAILURE) {
 685                         wpa_printf(MSG_INFO, "EAP-AKA: Unexpected response "
 686                                    "subtype %d", subtype);
 687                         return TRUE;
 688                 }
 689                 break;
 690         case REAUTH:
 691                 if (subtype != EAP_AKA_SUBTYPE_REAUTHENTICATION) {
 692                         wpa_printf(MSG_INFO, "EAP-AKA: Unexpected response "
 693                                    "subtype %d", subtype);
 694                         return TRUE;
 695                 }
 696                 break;
 697         case NOTIFICATION:
 698                 if (subtype != EAP_AKA_SUBTYPE_NOTIFICATION) {
 699                         wpa_printf(MSG_INFO, "EAP-AKA: Unexpected response "
 700                                    "subtype %d", subtype);
 701                         return TRUE;
 702                 }
 703                 break;
 704         default:
 705                 wpa_printf(MSG_INFO, "EAP-AKA: Unexpected state (%d) for "
 706                            "processing a response", data->state);
 707                 return TRUE;
 708         }
 709
 710         return FALSE;
 711 }
 712
 713
 714 static void eap_aka_determine_identity(struct eap_sm *sm,
 715                                        struct eap_aka_data *data)
 716 {
 717         char *username;
 718
 719         wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA: Identity",
 720                           sm->identity, sm->identity_len);
 721
 722         username = sim_get_username(sm->identity, sm->identity_len);
 723         if (username == NULL) {
 724                 data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
 725                 eap_aka_state(data, NOTIFICATION);
 726                 return;
 727         }
 728
 729         if (eap_aka_check_identity_reauth(sm, data, username) > 0) {
 730                 os_free(username);
 731                 return;
 732         }
 733
 734         if (((data->eap_method == EAP_TYPE_AKA_PRIME &&
 735               username[0] == EAP_AKA_PRIME_REAUTH_ID_PREFIX) ||
 736              (data->eap_method == EAP_TYPE_AKA &&
 737               username[0] == EAP_AKA_REAUTH_ID_PREFIX)) &&
 738             data->identity_round == 1) {
 739                 /* Remain in IDENTITY state for another round to request full
 740                  * auth identity since we did not recognize reauth id */
 741                 os_free(username);
 742                 return;
 743         }
 744
 745         if ((data->eap_method == EAP_TYPE_AKA_PRIME &&
 746              username[0] == EAP_AKA_PRIME_PSEUDONYM_PREFIX) ||
 747             (data->eap_method == EAP_TYPE_AKA &&
 748              username[0] == EAP_AKA_PSEUDONYM_PREFIX)) {
 749                 const char *permanent;
 750                 wpa_printf(MSG_DEBUG, "EAP-AKA: Pseudonym username '%s'",
 751                            username);
 752                 permanent = eap_sim_db_get_permanent(
 753                         sm->eap_sim_db_priv, username);
 754                 os_free(username);
 755                 if (permanent == NULL) {
 756                         wpa_printf(MSG_DEBUG, "EAP-AKA: Unknown pseudonym "
 757                                    "identity - request permanent identity");
 758                         /* Remain in IDENTITY state for another round */
 759                         return;
 760                 }
 761                 os_strlcpy(data->permanent, permanent,
 762                            sizeof(data->permanent));
 763         } else if ((data->eap_method == EAP_TYPE_AKA_PRIME &&
 764                     username[0] == EAP_AKA_PRIME_PERMANENT_PREFIX) ||
 765                    (data->eap_method == EAP_TYPE_AKA &&
 766                     username[0] == EAP_AKA_PERMANENT_PREFIX)) {
 767                 wpa_printf(MSG_DEBUG, "EAP-AKA: Permanent username '%s'",
 768                            username);
 769                 os_strlcpy(data->permanent, username, sizeof(data->permanent));
 770                 os_free(username);
 771         } else {
 772                 wpa_printf(MSG_DEBUG, "EAP-AKA: Unrecognized username '%s'",
 773                            username);
 774                 os_free(username);
 775                 data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
 776                 eap_aka_state(data, NOTIFICATION);
 777                 return;
 778         }
 779
 780         eap_aka_fullauth(sm, data);
 781 }
 782
 783
 784 static void eap_aka_fullauth(struct eap_sm *sm, struct eap_aka_data *data)
 785 {
 786         size_t identity_len;
 787         int res;
 788
 789         res = eap_sim_db_get_aka_auth(sm->eap_sim_db_priv, data->permanent,
 790                                       data->rand, data->autn, data->ik,
 791                                       data->ck, data->res, &data->res_len, sm);
 792         if (res == EAP_SIM_DB_PENDING) {
 793                 wpa_printf(MSG_DEBUG, "EAP-AKA: AKA authentication data "
 794                            "not yet available - pending request");
 795                 sm->method_pending = METHOD_PENDING_WAIT;
 796                 return;
 797         }
 798
 799         if (data->permanent[0] == EAP_AKA_PERMANENT_PREFIX ||
 800             data->permanent[0] == EAP_AKA_PRIME_PERMANENT_PREFIX)
 801                 os_strlcpy(sm->imsi, &data->permanent[1], sizeof(sm->imsi));
 802
 803 #ifdef EAP_SERVER_AKA_PRIME
 804         if (data->eap_method == EAP_TYPE_AKA_PRIME) {
 805                 /* Note: AUTN = (SQN ^ AK) || AMF || MAC which gives us the
 806                  * needed 6-octet SQN ^AK for CK',IK' derivation */
 807                 eap_aka_prime_derive_ck_ik_prime(data->ck, data->ik,
 808                                                  data->autn,
 809                                                  data->network_name,
 810                                                  data->network_name_len);
 811         }
 812 #endif /* EAP_SERVER_AKA_PRIME */
 813
 814         data->reauth = NULL;
 815         data->counter = 0; /* reset re-auth counter since this is full auth */
 816
 817         if (res != 0) {
 818                 wpa_printf(MSG_INFO, "EAP-AKA: Failed to get AKA "
 819                            "authentication data for the peer");
 820                 data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
 821                 eap_aka_state(data, NOTIFICATION);
 822                 return;
 823         }
 824         if (sm->method_pending == METHOD_PENDING_WAIT) {
 825                 wpa_printf(MSG_DEBUG, "EAP-AKA: AKA authentication data "
 826                            "available - abort pending wait");
 827                 sm->method_pending = METHOD_PENDING_NONE;
 828         }
 829
 830         identity_len = sm->identity_len;
 831         while (identity_len > 0 && sm->identity[identity_len - 1] == '\0') {
 832                 wpa_printf(MSG_DEBUG, "EAP-AKA: Workaround - drop last null "
 833                            "character from identity");
 834                 identity_len--;
 835         }
 836         wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA: Identity for MK derivation",
 837                           sm->identity, identity_len);
 838
 839         if (data->eap_method == EAP_TYPE_AKA_PRIME) {
 840                 eap_aka_prime_derive_keys(sm->identity, identity_len, data->ik,
 841                                           data->ck, data->k_encr, data->k_aut,
 842                                           data->k_re, data->msk, data->emsk);
 843         } else {
 844                 eap_aka_derive_mk(sm->identity, identity_len, data->ik,
 845                                   data->ck, data->mk);
 846                 eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut,
 847                                     data->msk, data->emsk);
 848         }
 849
 850         eap_aka_state(data, CHALLENGE);
 851 }
 852
 853
 854 static void eap_aka_process_identity(struct eap_sm *sm,
 855                                      struct eap_aka_data *data,
 856                                      struct wpabuf *respData,
 857                                      struct eap_sim_attrs *attr)
 858 {
 859         u8 *new_identity;
 860
 861         wpa_printf(MSG_DEBUG, "EAP-AKA: Processing Identity");
 862
 863         if (attr->mac || attr->iv || attr->encr_data) {
 864                 wpa_printf(MSG_WARNING, "EAP-AKA: Unexpected attribute "
 865                            "received in EAP-Response/AKA-Identity");
 866                 data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
 867                 eap_aka_state(data, NOTIFICATION);
 868                 return;
 869         }
 870
 871         /*
 872          * We always request identity with AKA/Identity, so the peer is
 873          * required to have replied with one.
 874          */
 875         if (!attr->identity || attr->identity_len == 0) {
 876                 wpa_printf(MSG_DEBUG, "EAP-AKA: Peer did not provide any "
 877                            "identity");
 878                 data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
 879                 eap_aka_state(data, NOTIFICATION);
 880                 return;
 881         }
 882
 883         new_identity = os_malloc(attr->identity_len);
 884         if (new_identity == NULL) {
 885                 data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
 886                 eap_aka_state(data, NOTIFICATION);
 887                 return;
 888         }
 889         os_free(sm->identity);
 890         sm->identity = new_identity;
 891         os_memcpy(sm->identity, attr->identity, attr->identity_len);
 892         sm->identity_len = attr->identity_len;
 893
 894         eap_aka_determine_identity(sm, data);
 895         if (eap_get_id(respData) == data->pending_id) {
 896                 data->pending_id = -1;
 897                 eap_aka_add_id_msg(data, respData);
 898         }
 899 }
 900
 901
 902 static int eap_aka_verify_mac(struct eap_aka_data *data,
 903                               const struct wpabuf *req,
 904                               const u8 *mac, const u8 *extra,
 905                               size_t extra_len)
 906 {
 907         if (data->eap_method == EAP_TYPE_AKA_PRIME)
 908                 return eap_sim_verify_mac_sha256(data->k_aut, req, mac, extra,
 909                                                  extra_len);
 910         return eap_sim_verify_mac(data->k_aut, req, mac, extra, extra_len);
 911 }
 912
 913
 914 static void eap_aka_process_challenge(struct eap_sm *sm,
 915                                       struct eap_aka_data *data,
 916                                       struct wpabuf *respData,
 917                                       struct eap_sim_attrs *attr)
 918 {
 919         wpa_printf(MSG_DEBUG, "EAP-AKA: Processing Challenge");
 920
 921 #ifdef EAP_SERVER_AKA_PRIME
 922 #if 0
 923         /* KDF negotiation; to be enabled only after more than one KDF is
 924          * supported */
 925         if (data->eap_method == EAP_TYPE_AKA_PRIME &&
 926             attr->kdf_count == 1 && attr->mac == NULL) {
 927                 if (attr->kdf[0] != EAP_AKA_PRIME_KDF) {
 928                         wpa_printf(MSG_WARNING, "EAP-AKA': Peer selected "
 929                                    "unknown KDF");
 930                         data->notification =
 931                                 EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
 932                         eap_aka_state(data, NOTIFICATION);
 933                         return;
 934                 }
 935
 936                 data->kdf = attr->kdf[0];
 937
 938                 /* Allow negotiation to continue with the selected KDF by
 939                  * sending another Challenge message */
 940                 wpa_printf(MSG_DEBUG, "EAP-AKA': KDF %d selected", data->kdf);
 941                 return;
 942         }
 943 #endif
 944 #endif /* EAP_SERVER_AKA_PRIME */
 945
 946         if (attr->checkcode &&
 947             eap_aka_verify_checkcode(data, attr->checkcode,
 948                                      attr->checkcode_len)) {
 949                 wpa_printf(MSG_WARNING, "EAP-AKA: Invalid AT_CHECKCODE in the "
 950                            "message");
 951                 data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
 952                 eap_aka_state(data, NOTIFICATION);
 953                 return;
 954         }
 955         if (attr->mac == NULL ||
 956             eap_aka_verify_mac(data, respData, attr->mac, NULL, 0)) {
 957                 wpa_printf(MSG_WARNING, "EAP-AKA: Challenge message "
 958                            "did not include valid AT_MAC");
 959                 data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
 960                 eap_aka_state(data, NOTIFICATION);
 961                 return;
 962         }
 963
 964         /*
 965          * AT_RES is padded, so verify that there is enough room for RES and
 966          * that the RES length in bits matches with the expected RES.
 967          */
 968         if (attr->res == NULL || attr->res_len < data->res_len ||
 969             attr->res_len_bits != data->res_len * 8 ||
 970             os_memcmp_const(attr->res, data->res, data->res_len) != 0) {
 971                 wpa_printf(MSG_WARNING, "EAP-AKA: Challenge message did not "
 972                            "include valid AT_RES (attr len=%lu, res len=%lu "
 973                            "bits, expected %lu bits)",
 974                            (unsigned long) attr->res_len,
 975                            (unsigned long) attr->res_len_bits,
 976                            (unsigned long) data->res_len * 8);
 977                 data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
 978                 eap_aka_state(data, NOTIFICATION);
 979                 return;
 980         }
 981
 982         wpa_printf(MSG_DEBUG, "EAP-AKA: Challenge response includes the "
 983                    "correct AT_MAC");
 984         if (sm->eap_sim_aka_result_ind && attr->result_ind) {
 985                 data->use_result_ind = 1;
 986                 data->notification = EAP_SIM_SUCCESS;
 987                 eap_aka_state(data, NOTIFICATION);
 988         } else
 989                 eap_aka_state(data, SUCCESS);
 990
 991         if (data->next_pseudonym) {
 992                 eap_sim_db_add_pseudonym(sm->eap_sim_db_priv, data->permanent,
 993                                          data->next_pseudonym);
 994                 data->next_pseudonym = NULL;
 995         }
 996         if (data->next_reauth_id) {
 997                 if (data->eap_method == EAP_TYPE_AKA_PRIME) {
 998 #ifdef EAP_SERVER_AKA_PRIME
 999                         eap_sim_db_add_reauth_prime(sm->eap_sim_db_priv,
1000                                                     data->permanent,
1001                                                     data->next_reauth_id,
1002                                                     data->counter + 1,
1003                                                     data->k_encr, data->k_aut,
1004                                                     data->k_re);
1005 #endif /* EAP_SERVER_AKA_PRIME */
1006                 } else {
1007                         eap_sim_db_add_reauth(sm->eap_sim_db_priv,
1008                                               data->permanent,
1009                                               data->next_reauth_id,
1010                                               data->counter + 1,
1011                                               data->mk);
1012                 }
1013                 data->next_reauth_id = NULL;
1014         }
1015 }
1016
1017
1018 static void eap_aka_process_sync_failure(struct eap_sm *sm,
1019                                          struct eap_aka_data *data,
1020                                          struct wpabuf *respData,
1021                                          struct eap_sim_attrs *attr)
1022 {
1023         wpa_printf(MSG_DEBUG, "EAP-AKA: Processing Synchronization-Failure");
1024
1025         if (attr->auts == NULL) {
1026                 wpa_printf(MSG_WARNING, "EAP-AKA: Synchronization-Failure "
1027                            "message did not include valid AT_AUTS");
1028                 data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
1029                 eap_aka_state(data, NOTIFICATION);
1030                 return;
1031         }
1032
1033         /* Avoid re-reporting AUTS when processing pending EAP packet by
1034          * maintaining a local flag stating whether this AUTS has already been
1035          * reported. */
1036         if (!data->auts_reported &&
1037             eap_sim_db_resynchronize(sm->eap_sim_db_priv, data->permanent,
1038                                      attr->auts, data->rand)) {
1039                 wpa_printf(MSG_WARNING, "EAP-AKA: Resynchronization failed");
1040                 data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
1041                 eap_aka_state(data, NOTIFICATION);
1042                 return;
1043         }
1044         data->auts_reported = 1;
1045
1046         /* Remain in CHALLENGE state to re-try after resynchronization */
1047         eap_aka_fullauth(sm, data);
1048 }
1049
1050
1051 static void eap_aka_process_reauth(struct eap_sm *sm,
1052                                    struct eap_aka_data *data,
1053                                    struct wpabuf *respData,
1054                                    struct eap_sim_attrs *attr)
1055 {
1056         struct eap_sim_attrs eattr;
1057         u8 *decrypted = NULL;
1058
1059         wpa_printf(MSG_DEBUG, "EAP-AKA: Processing Reauthentication");
1060
1061         if (attr->mac == NULL ||
1062             eap_aka_verify_mac(data, respData, attr->mac, data->nonce_s,
1063                                EAP_SIM_NONCE_S_LEN)) {
1064                 wpa_printf(MSG_WARNING, "EAP-AKA: Re-authentication message "
1065                            "did not include valid AT_MAC");
1066                 goto fail;
1067         }
1068
1069         if (attr->encr_data == NULL || attr->iv == NULL) {
1070                 wpa_printf(MSG_WARNING, "EAP-AKA: Reauthentication "
1071                            "message did not include encrypted data");
1072                 goto fail;
1073         }
1074
1075         decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
1076                                        attr->encr_data_len, attr->iv, &eattr,
1077                                        0);
1078         if (decrypted == NULL) {
1079                 wpa_printf(MSG_WARNING, "EAP-AKA: Failed to parse encrypted "
1080                            "data from reauthentication message");
1081                 goto fail;
1082         }
1083
1084         if (eattr.counter != data->counter) {
1085                 wpa_printf(MSG_WARNING, "EAP-AKA: Re-authentication message "
1086                            "used incorrect counter %u, expected %u",
1087                            eattr.counter, data->counter);
1088                 goto fail;
1089         }
1090         os_free(decrypted);
1091         decrypted = NULL;
1092
1093         wpa_printf(MSG_DEBUG, "EAP-AKA: Re-authentication response includes "
1094                    "the correct AT_MAC");
1095
1096         if (eattr.counter_too_small) {
1097                 wpa_printf(MSG_DEBUG, "EAP-AKA: Re-authentication response "
1098                            "included AT_COUNTER_TOO_SMALL - starting full "
1099                            "authentication");
1100                 eap_aka_fullauth(sm, data);
1101                 return;
1102         }
1103
1104         if (sm->eap_sim_aka_result_ind && attr->result_ind) {
1105                 data->use_result_ind = 1;
1106                 data->notification = EAP_SIM_SUCCESS;
1107                 eap_aka_state(data, NOTIFICATION);
1108         } else
1109                 eap_aka_state(data, SUCCESS);
1110
1111         if (data->next_reauth_id) {
1112                 if (data->eap_method == EAP_TYPE_AKA_PRIME) {
1113 #ifdef EAP_SERVER_AKA_PRIME
1114                         eap_sim_db_add_reauth_prime(sm->eap_sim_db_priv,
1115                                                     data->permanent,
1116                                                     data->next_reauth_id,
1117                                                     data->counter + 1,
1118                                                     data->k_encr, data->k_aut,
1119                                                     data->k_re);
1120 #endif /* EAP_SERVER_AKA_PRIME */
1121                 } else {
1122                         eap_sim_db_add_reauth(sm->eap_sim_db_priv,
1123                                               data->permanent,
1124                                               data->next_reauth_id,
1125                                               data->counter + 1,
1126                                               data->mk);
1127                 }
1128                 data->next_reauth_id = NULL;
1129         } else {
1130                 eap_sim_db_remove_reauth(sm->eap_sim_db_priv, data->reauth);
1131                 data->reauth = NULL;
1132         }
1133
1134         return;
1135
1136 fail:
1137         data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
1138         eap_aka_state(data, NOTIFICATION);
1139         eap_sim_db_remove_reauth(sm->eap_sim_db_priv, data->reauth);
1140         data->reauth = NULL;
1141         os_free(decrypted);
1142 }
1143
1144
1145 static void eap_aka_process_client_error(struct eap_sm *sm,
1146                                          struct eap_aka_data *data,
1147                                          struct wpabuf *respData,
1148                                          struct eap_sim_attrs *attr)
1149 {
1150         wpa_printf(MSG_DEBUG, "EAP-AKA: Client reported error %d",
1151                    attr->client_error_code);
1152         if (data->notification == EAP_SIM_SUCCESS && data->use_result_ind)
1153                 eap_aka_state(data, SUCCESS);
1154         else
1155                 eap_aka_state(data, FAILURE);
1156 }
1157
1158
1159 static void eap_aka_process_authentication_reject(
1160         struct eap_sm *sm, struct eap_aka_data *data,
1161         struct wpabuf *respData, struct eap_sim_attrs *attr)
1162 {
1163         wpa_printf(MSG_DEBUG, "EAP-AKA: Client rejected authentication");
1164         eap_aka_state(data, FAILURE);
1165 }
1166
1167
1168 static void eap_aka_process_notification(struct eap_sm *sm,
1169                                          struct eap_aka_data *data,
1170                                          struct wpabuf *respData,
1171                                          struct eap_sim_attrs *attr)
1172 {
1173         wpa_printf(MSG_DEBUG, "EAP-AKA: Client replied to notification");
1174         if (data->notification == EAP_SIM_SUCCESS && data->use_result_ind)
1175                 eap_aka_state(data, SUCCESS);
1176         else
1177                 eap_aka_state(data, FAILURE);
1178 }
1179
1180
1181 static void eap_aka_process(struct eap_sm *sm, void *priv,
1182                             struct wpabuf *respData)
1183 {
1184         struct eap_aka_data *data = priv;
1185         const u8 *pos, *end;
1186         u8 subtype;
1187         size_t len;
1188         struct eap_sim_attrs attr;
1189
1190         pos = eap_hdr_validate(EAP_VENDOR_IETF, data->eap_method, respData,
1191                                &len);
1192         if (pos == NULL || len < 3)
1193                 return;
1194
1195         end = pos + len;
1196         subtype = *pos;
1197         pos += 3;
1198
1199         if (eap_aka_subtype_ok(data, subtype)) {
1200                 wpa_printf(MSG_DEBUG, "EAP-AKA: Unrecognized or unexpected "
1201                            "EAP-AKA Subtype in EAP Response");
1202                 data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
1203                 eap_aka_state(data, NOTIFICATION);
1204                 return;
1205         }
1206
1207         if (eap_sim_parse_attr(pos, end, &attr,
1208                                data->eap_method == EAP_TYPE_AKA_PRIME ? 2 : 1,
1209                                0)) {
1210                 wpa_printf(MSG_DEBUG, "EAP-AKA: Failed to parse attributes");
1211                 data->notification = EAP_SIM_GENERAL_FAILURE_BEFORE_AUTH;
1212                 eap_aka_state(data, NOTIFICATION);
1213                 return;
1214         }
1215
1216         if (subtype == EAP_AKA_SUBTYPE_CLIENT_ERROR) {
1217                 eap_aka_process_client_error(sm, data, respData, &attr);
1218                 return;
1219         }
1220
1221         if (subtype == EAP_AKA_SUBTYPE_AUTHENTICATION_REJECT) {
1222                 eap_aka_process_authentication_reject(sm, data, respData,
1223                                                       &attr);
1224                 return;
1225         }
1226
1227         switch (data->state) {
1228         case IDENTITY:
1229                 eap_aka_process_identity(sm, data, respData, &attr);
1230                 break;
1231         case CHALLENGE:
1232                 if (subtype == EAP_AKA_SUBTYPE_SYNCHRONIZATION_FAILURE) {
1233                         eap_aka_process_sync_failure(sm, data, respData,
1234                                                      &attr);
1235                 } else {
1236                         eap_aka_process_challenge(sm, data, respData, &attr);
1237                 }
1238                 break;
1239         case REAUTH:
1240                 eap_aka_process_reauth(sm, data, respData, &attr);
1241                 break;
1242         case NOTIFICATION:
1243                 eap_aka_process_notification(sm, data, respData, &attr);
1244                 break;
1245         default:
1246                 wpa_printf(MSG_DEBUG, "EAP-AKA: Unknown state %d in "
1247                            "process", data->state);
1248                 break;
1249         }
1250 }
1251
1252
1253 static Boolean eap_aka_isDone(struct eap_sm *sm, void *priv)
1254 {
1255         struct eap_aka_data *data = priv;
1256         return data->state == SUCCESS || data->state == FAILURE;
1257 }
1258
1259
1260 static u8 * eap_aka_getKey(struct eap_sm *sm, void *priv, size_t *len)
1261 {
1262         struct eap_aka_data *data = priv;
1263         u8 *key;
1264
1265         if (data->state != SUCCESS)
1266                 return NULL;
1267
1268         key = os_memdup(data->msk, EAP_SIM_KEYING_DATA_LEN);
1269         if (key == NULL)
1270                 return NULL;
1271         *len = EAP_SIM_KEYING_DATA_LEN;
1272         return key;
1273 }
1274
1275
1276 static u8 * eap_aka_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
1277 {
1278         struct eap_aka_data *data = priv;
1279         u8 *key;
1280
1281         if (data->state != SUCCESS)
1282                 return NULL;
1283
1284         key = os_memdup(data->emsk, EAP_EMSK_LEN);
1285         if (key == NULL)
1286                 return NULL;
1287         *len = EAP_EMSK_LEN;
1288         return key;
1289 }
1290
1291
1292 static Boolean eap_aka_isSuccess(struct eap_sm *sm, void *priv)
1293 {
1294         struct eap_aka_data *data = priv;
1295         return data->state == SUCCESS;
1296 }
1297
1298
1299 static u8 * eap_aka_get_session_id(struct eap_sm *sm, void *priv, size_t *len)
1300 {
1301         struct eap_aka_data *data = priv;
1302         u8 *id;
1303
1304         if (data->state != SUCCESS)
1305                 return NULL;
1306
1307         *len = 1 + EAP_AKA_RAND_LEN + EAP_AKA_AUTN_LEN;
1308         id = os_malloc(*len);
1309         if (id == NULL)
1310                 return NULL;
1311
1312         id[0] = data->eap_method;
1313         os_memcpy(id + 1, data->rand, EAP_AKA_RAND_LEN);
1314         os_memcpy(id + 1 + EAP_AKA_RAND_LEN, data->autn, EAP_AKA_AUTN_LEN);
1315         wpa_hexdump(MSG_DEBUG, "EAP-AKA: Derived Session-Id", id, *len);
1316
1317         return id;
1318 }
1319
1320
1321 int eap_server_aka_register(void)
1322 {
1323         struct eap_method *eap;
1324
1325         eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
1326                                       EAP_VENDOR_IETF, EAP_TYPE_AKA, "AKA");
1327         if (eap == NULL)
1328                 return -1;
1329
1330         eap->init = eap_aka_init;
1331         eap->reset = eap_aka_reset;
1332         eap->buildReq = eap_aka_buildReq;
1333         eap->check = eap_aka_check;
1334         eap->process = eap_aka_process;
1335         eap->isDone = eap_aka_isDone;
1336         eap->getKey = eap_aka_getKey;
1337         eap->isSuccess = eap_aka_isSuccess;
1338         eap->get_emsk = eap_aka_get_emsk;
1339         eap->getSessionId = eap_aka_get_session_id;
1340
1341         return eap_server_method_register(eap);
1342 }
1343
1344
1345 #ifdef EAP_SERVER_AKA_PRIME
1346 int eap_server_aka_prime_register(void)
1347 {
1348         struct eap_method *eap;
1349
1350         eap = eap_server_method_alloc(EAP_SERVER_METHOD_INTERFACE_VERSION,
1351                                       EAP_VENDOR_IETF, EAP_TYPE_AKA_PRIME,
1352                                       "AKA'");
1353         if (eap == NULL)
1354                 return -1;
1355
1356         eap->init = eap_aka_prime_init;
1357         eap->reset = eap_aka_reset;
1358         eap->buildReq = eap_aka_buildReq;
1359         eap->check = eap_aka_check;
1360         eap->process = eap_aka_process;
1361         eap->isDone = eap_aka_isDone;
1362         eap->getKey = eap_aka_getKey;
1363         eap->isSuccess = eap_aka_isSuccess;
1364         eap->get_emsk = eap_aka_get_emsk;
1365         eap->getSessionId = eap_aka_get_session_id;
1366
1367         return eap_server_method_register(eap);
1368 }
1369 #endif /* EAP_SERVER_AKA_PRIME */