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      1 /*
      2  * EAP peer method: EAP-AKA (RFC 4187) and EAP-AKA' (RFC 5448)
      3  * Copyright (c) 2004-2012, Jouni Malinen <j (at) 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 "pcsc_funcs.h"
     13 #include "crypto/crypto.h"
     14 #include "crypto/sha1.h"
     15 #include "crypto/sha256.h"
     16 #include "crypto/milenage.h"
     17 #include "eap_common/eap_sim_common.h"
     18 #include "eap_config.h"
     19 #include "eap_i.h"
     20 
     21 
     22 struct eap_aka_data {
     23 	u8 ik[EAP_AKA_IK_LEN], ck[EAP_AKA_CK_LEN], res[EAP_AKA_RES_MAX_LEN];
     24 	size_t res_len;
     25 	u8 nonce_s[EAP_SIM_NONCE_S_LEN];
     26 	u8 mk[EAP_SIM_MK_LEN];
     27 	u8 k_aut[EAP_AKA_PRIME_K_AUT_LEN];
     28 	u8 k_encr[EAP_SIM_K_ENCR_LEN];
     29 	u8 k_re[EAP_AKA_PRIME_K_RE_LEN]; /* EAP-AKA' only */
     30 	u8 msk[EAP_SIM_KEYING_DATA_LEN];
     31 	u8 emsk[EAP_EMSK_LEN];
     32 	u8 rand[EAP_AKA_RAND_LEN], autn[EAP_AKA_AUTN_LEN];
     33 	u8 auts[EAP_AKA_AUTS_LEN];
     34 
     35 	int num_id_req, num_notification;
     36 	u8 *pseudonym;
     37 	size_t pseudonym_len;
     38 	u8 *reauth_id;
     39 	size_t reauth_id_len;
     40 	int reauth;
     41 	unsigned int counter, counter_too_small;
     42 	u8 *last_eap_identity;
     43 	size_t last_eap_identity_len;
     44 	enum {
     45 		CONTINUE, RESULT_SUCCESS, SUCCESS, FAILURE
     46 	} state;
     47 
     48 	struct wpabuf *id_msgs;
     49 	int prev_id;
     50 	int result_ind, use_result_ind;
     51 	u8 eap_method;
     52 	u8 *network_name;
     53 	size_t network_name_len;
     54 	u16 kdf;
     55 	int kdf_negotiation;
     56 };
     57 
     58 
     59 #ifndef CONFIG_NO_STDOUT_DEBUG
     60 static const char * eap_aka_state_txt(int state)
     61 {
     62 	switch (state) {
     63 	case CONTINUE:
     64 		return "CONTINUE";
     65 	case RESULT_SUCCESS:
     66 		return "RESULT_SUCCESS";
     67 	case SUCCESS:
     68 		return "SUCCESS";
     69 	case FAILURE:
     70 		return "FAILURE";
     71 	default:
     72 		return "?";
     73 	}
     74 }
     75 #endif /* CONFIG_NO_STDOUT_DEBUG */
     76 
     77 
     78 static void eap_aka_state(struct eap_aka_data *data, int state)
     79 {
     80 	wpa_printf(MSG_DEBUG, "EAP-AKA: %s -> %s",
     81 		   eap_aka_state_txt(data->state),
     82 		   eap_aka_state_txt(state));
     83 	data->state = state;
     84 }
     85 
     86 
     87 static void * eap_aka_init(struct eap_sm *sm)
     88 {
     89 	struct eap_aka_data *data;
     90 	const char *phase1 = eap_get_config_phase1(sm);
     91 	struct eap_peer_config *config = eap_get_config(sm);
     92 
     93 	data = os_zalloc(sizeof(*data));
     94 	if (data == NULL)
     95 		return NULL;
     96 
     97 	data->eap_method = EAP_TYPE_AKA;
     98 
     99 	eap_aka_state(data, CONTINUE);
    100 	data->prev_id = -1;
    101 
    102 	data->result_ind = phase1 && os_strstr(phase1, "result_ind=1") != NULL;
    103 
    104 	if (config && config->anonymous_identity) {
    105 		data->pseudonym = os_malloc(config->anonymous_identity_len);
    106 		if (data->pseudonym) {
    107 			os_memcpy(data->pseudonym, config->anonymous_identity,
    108 				  config->anonymous_identity_len);
    109 			data->pseudonym_len = config->anonymous_identity_len;
    110 		}
    111 	}
    112 
    113 	return data;
    114 }
    115 
    116 
    117 #ifdef EAP_AKA_PRIME
    118 static void * eap_aka_prime_init(struct eap_sm *sm)
    119 {
    120 	struct eap_aka_data *data = eap_aka_init(sm);
    121 	if (data == NULL)
    122 		return NULL;
    123 	data->eap_method = EAP_TYPE_AKA_PRIME;
    124 	return data;
    125 }
    126 #endif /* EAP_AKA_PRIME */
    127 
    128 
    129 static void eap_aka_clear_keys(struct eap_aka_data *data, int reauth)
    130 {
    131 	if (!reauth) {
    132 		os_memset(data->mk, 0, EAP_SIM_MK_LEN);
    133 		os_memset(data->k_aut, 0, EAP_AKA_PRIME_K_AUT_LEN);
    134 		os_memset(data->k_encr, 0, EAP_SIM_K_ENCR_LEN);
    135 		os_memset(data->k_re, 0, EAP_AKA_PRIME_K_RE_LEN);
    136 	}
    137 	os_memset(data->msk, 0, EAP_SIM_KEYING_DATA_LEN);
    138 	os_memset(data->emsk, 0, EAP_EMSK_LEN);
    139 	os_memset(data->autn, 0, EAP_AKA_AUTN_LEN);
    140 	os_memset(data->auts, 0, EAP_AKA_AUTS_LEN);
    141 }
    142 
    143 
    144 static void eap_aka_deinit(struct eap_sm *sm, void *priv)
    145 {
    146 	struct eap_aka_data *data = priv;
    147 	if (data) {
    148 		os_free(data->pseudonym);
    149 		os_free(data->reauth_id);
    150 		os_free(data->last_eap_identity);
    151 		wpabuf_free(data->id_msgs);
    152 		os_free(data->network_name);
    153 		eap_aka_clear_keys(data, 0);
    154 		os_free(data);
    155 	}
    156 }
    157 
    158 
    159 static int eap_aka_ext_sim_req(struct eap_sm *sm, struct eap_aka_data *data)
    160 {
    161 	char req[200], *pos, *end;
    162 
    163 	wpa_printf(MSG_DEBUG, "EAP-AKA: Use external USIM processing");
    164 	pos = req;
    165 	end = pos + sizeof(req);
    166 	pos += os_snprintf(pos, end - pos, "UMTS-AUTH");
    167 	pos += os_snprintf(pos, end - pos, ":");
    168 	pos += wpa_snprintf_hex(pos, end - pos, data->rand, EAP_AKA_RAND_LEN);
    169 	pos += os_snprintf(pos, end - pos, ":");
    170 	wpa_snprintf_hex(pos, end - pos, data->autn, EAP_AKA_AUTN_LEN);
    171 
    172 	eap_sm_request_sim(sm, req);
    173 	return 1;
    174 }
    175 
    176 
    177 static int eap_aka_ext_sim_result(struct eap_sm *sm, struct eap_aka_data *data,
    178 				  struct eap_peer_config *conf)
    179 {
    180 	char *resp, *pos;
    181 
    182 	wpa_printf(MSG_DEBUG,
    183 		   "EAP-AKA: Use result from external USIM processing");
    184 
    185 	resp = conf->external_sim_resp;
    186 	conf->external_sim_resp = NULL;
    187 
    188 	if (os_strncmp(resp, "UMTS-AUTS:", 10) == 0) {
    189 		pos = resp + 10;
    190 		if (hexstr2bin(pos, data->auts, EAP_AKA_AUTS_LEN) < 0)
    191 			goto invalid;
    192 		wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: AUTS", data->auts,
    193 				EAP_AKA_AUTS_LEN);
    194 		os_free(resp);
    195 		return -2;
    196 	}
    197 
    198 	if (os_strncmp(resp, "UMTS-AUTH:", 10) != 0) {
    199 		wpa_printf(MSG_DEBUG, "EAP-AKA: Unrecognized external USIM processing response");
    200 		os_free(resp);
    201 		return -1;
    202 	}
    203 
    204 	pos = resp + 10;
    205 	wpa_hexdump(MSG_DEBUG, "EAP-AKA: RAND", data->rand, EAP_AKA_RAND_LEN);
    206 
    207 	if (hexstr2bin(pos, data->ik, EAP_AKA_IK_LEN) < 0)
    208 		goto invalid;
    209 	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: IK", data->ik, EAP_AKA_IK_LEN);
    210 	pos += EAP_AKA_IK_LEN * 2;
    211 	if (*pos != ':')
    212 		goto invalid;
    213 	pos++;
    214 
    215 	if (hexstr2bin(pos, data->ck, EAP_AKA_CK_LEN) < 0)
    216 		goto invalid;
    217 	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: CK", data->ck, EAP_AKA_CK_LEN);
    218 	pos += EAP_AKA_CK_LEN * 2;
    219 	if (*pos != ':')
    220 		goto invalid;
    221 	pos++;
    222 
    223 	data->res_len = os_strlen(pos) / 2;
    224 	if (data->res_len > EAP_AKA_RES_MAX_LEN) {
    225 		data->res_len = 0;
    226 		goto invalid;
    227 	}
    228 	if (hexstr2bin(pos, data->res, data->res_len) < 0)
    229 		goto invalid;
    230 	wpa_hexdump_key(MSG_DEBUG, "EAP-AKA: RES", data->res, data->res_len);
    231 
    232 	os_free(resp);
    233 	return 0;
    234 
    235 invalid:
    236 	wpa_printf(MSG_DEBUG, "EAP-AKA: Invalid external USIM processing UMTS-AUTH response");
    237 	os_free(resp);
    238 	return -1;
    239 }
    240 
    241 
    242 static int eap_aka_umts_auth(struct eap_sm *sm, struct eap_aka_data *data)
    243 {
    244 	struct eap_peer_config *conf;
    245 
    246 	wpa_printf(MSG_DEBUG, "EAP-AKA: UMTS authentication algorithm");
    247 
    248 	conf = eap_get_config(sm);
    249 	if (conf == NULL)
    250 		return -1;
    251 
    252 	if (sm->external_sim) {
    253 		if (conf->external_sim_resp)
    254 			return eap_aka_ext_sim_result(sm, data, conf);
    255 		else
    256 			return eap_aka_ext_sim_req(sm, data);
    257 	}
    258 
    259 	if (conf->pcsc) {
    260 		return scard_umts_auth(sm->scard_ctx, data->rand,
    261 				       data->autn, data->res, &data->res_len,
    262 				       data->ik, data->ck, data->auts);
    263 	}
    264 
    265 #ifdef CONFIG_USIM_SIMULATOR
    266 	if (conf->password) {
    267 		u8 opc[16], k[16], sqn[6];
    268 		const char *pos;
    269 		wpa_printf(MSG_DEBUG, "EAP-AKA: Use internal Milenage "
    270 			   "implementation for UMTS authentication");
    271 		if (conf->password_len < 78) {
    272 			wpa_printf(MSG_DEBUG, "EAP-AKA: invalid Milenage "
    273 				   "password");
    274 			return -1;
    275 		}
    276 		pos = (const char *) conf->password;
    277 		if (hexstr2bin(pos, k, 16))
    278 			return -1;
    279 		pos += 32;
    280 		if (*pos != ':')
    281 			return -1;
    282 		pos++;
    283 
    284 		if (hexstr2bin(pos, opc, 16))
    285 			return -1;
    286 		pos += 32;
    287 		if (*pos != ':')
    288 			return -1;
    289 		pos++;
    290 
    291 		if (hexstr2bin(pos, sqn, 6))
    292 			return -1;
    293 
    294 		return milenage_check(opc, k, sqn, data->rand, data->autn,
    295 				      data->ik, data->ck,
    296 				      data->res, &data->res_len, data->auts);
    297 	}
    298 #endif /* CONFIG_USIM_SIMULATOR */
    299 
    300 #ifdef CONFIG_USIM_HARDCODED
    301 	wpa_printf(MSG_DEBUG, "EAP-AKA: Use hardcoded Kc and SRES values for "
    302 		   "testing");
    303 
    304 	/* These hardcoded Kc and SRES values are used for testing.
    305 	 * Could consider making them configurable. */
    306 	os_memset(data->res, '2', EAP_AKA_RES_MAX_LEN);
    307 	data->res_len = EAP_AKA_RES_MAX_LEN;
    308 	os_memset(data->ik, '3', EAP_AKA_IK_LEN);
    309 	os_memset(data->ck, '4', EAP_AKA_CK_LEN);
    310 	{
    311 		u8 autn[EAP_AKA_AUTN_LEN];
    312 		os_memset(autn, '1', EAP_AKA_AUTN_LEN);
    313 		if (os_memcmp_const(autn, data->autn, EAP_AKA_AUTN_LEN) != 0) {
    314 			wpa_printf(MSG_WARNING, "EAP-AKA: AUTN did not match "
    315 				   "with expected value");
    316 			return -1;
    317 		}
    318 	}
    319 #if 0
    320 	{
    321 		static int test_resync = 1;
    322 		if (test_resync) {
    323 			/* Test Resynchronization */
    324 			test_resync = 0;
    325 			return -2;
    326 		}
    327 	}
    328 #endif
    329 	return 0;
    330 
    331 #else /* CONFIG_USIM_HARDCODED */
    332 
    333 	wpa_printf(MSG_DEBUG, "EAP-AKA: No UMTS authentication algorithm "
    334 		   "enabled");
    335 	return -1;
    336 
    337 #endif /* CONFIG_USIM_HARDCODED */
    338 }
    339 
    340 
    341 #define CLEAR_PSEUDONYM	0x01
    342 #define CLEAR_REAUTH_ID	0x02
    343 #define CLEAR_EAP_ID	0x04
    344 
    345 static void eap_aka_clear_identities(struct eap_sm *sm,
    346 				     struct eap_aka_data *data, int id)
    347 {
    348 	if ((id & CLEAR_PSEUDONYM) && data->pseudonym) {
    349 		wpa_printf(MSG_DEBUG, "EAP-AKA: forgetting old pseudonym");
    350 		os_free(data->pseudonym);
    351 		data->pseudonym = NULL;
    352 		data->pseudonym_len = 0;
    353 		eap_set_anon_id(sm, NULL, 0);
    354 	}
    355 	if ((id & CLEAR_REAUTH_ID) && data->reauth_id) {
    356 		wpa_printf(MSG_DEBUG, "EAP-AKA: forgetting old reauth_id");
    357 		os_free(data->reauth_id);
    358 		data->reauth_id = NULL;
    359 		data->reauth_id_len = 0;
    360 	}
    361 	if ((id & CLEAR_EAP_ID) && data->last_eap_identity) {
    362 		wpa_printf(MSG_DEBUG, "EAP-AKA: forgetting old eap_id");
    363 		os_free(data->last_eap_identity);
    364 		data->last_eap_identity = NULL;
    365 		data->last_eap_identity_len = 0;
    366 	}
    367 }
    368 
    369 
    370 static int eap_aka_learn_ids(struct eap_sm *sm, struct eap_aka_data *data,
    371 			     struct eap_sim_attrs *attr)
    372 {
    373 	if (attr->next_pseudonym) {
    374 		const u8 *identity = NULL;
    375 		size_t identity_len = 0;
    376 		const u8 *realm = NULL;
    377 		size_t realm_len = 0;
    378 
    379 		wpa_hexdump_ascii(MSG_DEBUG,
    380 				  "EAP-AKA: (encr) AT_NEXT_PSEUDONYM",
    381 				  attr->next_pseudonym,
    382 				  attr->next_pseudonym_len);
    383 		os_free(data->pseudonym);
    384 		/* Look for the realm of the permanent identity */
    385 		identity = eap_get_config_identity(sm, &identity_len);
    386 		if (identity) {
    387 			for (realm = identity, realm_len = identity_len;
    388 			     realm_len > 0; realm_len--, realm++) {
    389 				if (*realm == '@')
    390 					break;
    391 			}
    392 		}
    393 		data->pseudonym = os_malloc(attr->next_pseudonym_len +
    394 					    realm_len);
    395 		if (data->pseudonym == NULL) {
    396 			wpa_printf(MSG_INFO, "EAP-AKA: (encr) No memory for "
    397 				   "next pseudonym");
    398 			data->pseudonym_len = 0;
    399 			return -1;
    400 		}
    401 		os_memcpy(data->pseudonym, attr->next_pseudonym,
    402 			  attr->next_pseudonym_len);
    403 		if (realm_len) {
    404 			os_memcpy(data->pseudonym + attr->next_pseudonym_len,
    405 				  realm, realm_len);
    406 		}
    407 		data->pseudonym_len = attr->next_pseudonym_len + realm_len;
    408 		eap_set_anon_id(sm, data->pseudonym, data->pseudonym_len);
    409 	}
    410 
    411 	if (attr->next_reauth_id) {
    412 		os_free(data->reauth_id);
    413 		data->reauth_id = os_malloc(attr->next_reauth_id_len);
    414 		if (data->reauth_id == NULL) {
    415 			wpa_printf(MSG_INFO, "EAP-AKA: (encr) No memory for "
    416 				   "next reauth_id");
    417 			data->reauth_id_len = 0;
    418 			return -1;
    419 		}
    420 		os_memcpy(data->reauth_id, attr->next_reauth_id,
    421 			  attr->next_reauth_id_len);
    422 		data->reauth_id_len = attr->next_reauth_id_len;
    423 		wpa_hexdump_ascii(MSG_DEBUG,
    424 				  "EAP-AKA: (encr) AT_NEXT_REAUTH_ID",
    425 				  data->reauth_id,
    426 				  data->reauth_id_len);
    427 	}
    428 
    429 	return 0;
    430 }
    431 
    432 
    433 static int eap_aka_add_id_msg(struct eap_aka_data *data,
    434 			      const struct wpabuf *msg)
    435 {
    436 	if (msg == NULL)
    437 		return -1;
    438 
    439 	if (data->id_msgs == NULL) {
    440 		data->id_msgs = wpabuf_dup(msg);
    441 		return data->id_msgs == NULL ? -1 : 0;
    442 	}
    443 
    444 	if (wpabuf_resize(&data->id_msgs, wpabuf_len(msg)) < 0)
    445 		return -1;
    446 	wpabuf_put_buf(data->id_msgs, msg);
    447 
    448 	return 0;
    449 }
    450 
    451 
    452 static void eap_aka_add_checkcode(struct eap_aka_data *data,
    453 				  struct eap_sim_msg *msg)
    454 {
    455 	const u8 *addr;
    456 	size_t len;
    457 	u8 hash[SHA256_MAC_LEN];
    458 
    459 	wpa_printf(MSG_DEBUG, "   AT_CHECKCODE");
    460 
    461 	if (data->id_msgs == NULL) {
    462 		/*
    463 		 * No EAP-AKA/Identity packets were exchanged - send empty
    464 		 * checkcode.
    465 		 */
    466 		eap_sim_msg_add(msg, EAP_SIM_AT_CHECKCODE, 0, NULL, 0);
    467 		return;
    468 	}
    469 
    470 	/* Checkcode is SHA1/SHA256 hash over all EAP-AKA/Identity packets. */
    471 	addr = wpabuf_head(data->id_msgs);
    472 	len = wpabuf_len(data->id_msgs);
    473 	wpa_hexdump(MSG_MSGDUMP, "EAP-AKA: AT_CHECKCODE data", addr, len);
    474 #ifdef EAP_AKA_PRIME
    475 	if (data->eap_method == EAP_TYPE_AKA_PRIME)
    476 		sha256_vector(1, &addr, &len, hash);
    477 	else
    478 #endif /* EAP_AKA_PRIME */
    479 		sha1_vector(1, &addr, &len, hash);
    480 
    481 	eap_sim_msg_add(msg, EAP_SIM_AT_CHECKCODE, 0, hash,
    482 			data->eap_method == EAP_TYPE_AKA_PRIME ?
    483 			EAP_AKA_PRIME_CHECKCODE_LEN : EAP_AKA_CHECKCODE_LEN);
    484 }
    485 
    486 
    487 static int eap_aka_verify_checkcode(struct eap_aka_data *data,
    488 				    const u8 *checkcode, size_t checkcode_len)
    489 {
    490 	const u8 *addr;
    491 	size_t len;
    492 	u8 hash[SHA256_MAC_LEN];
    493 	size_t hash_len;
    494 
    495 	if (checkcode == NULL)
    496 		return -1;
    497 
    498 	if (data->id_msgs == NULL) {
    499 		if (checkcode_len != 0) {
    500 			wpa_printf(MSG_DEBUG, "EAP-AKA: Checkcode from server "
    501 				   "indicates that AKA/Identity messages were "
    502 				   "used, but they were not");
    503 			return -1;
    504 		}
    505 		return 0;
    506 	}
    507 
    508 	hash_len = data->eap_method == EAP_TYPE_AKA_PRIME ?
    509 		EAP_AKA_PRIME_CHECKCODE_LEN : EAP_AKA_CHECKCODE_LEN;
    510 
    511 	if (checkcode_len != hash_len) {
    512 		wpa_printf(MSG_DEBUG, "EAP-AKA: Checkcode from server "
    513 			   "indicates that AKA/Identity message were not "
    514 			   "used, but they were");
    515 		return -1;
    516 	}
    517 
    518 	/* Checkcode is SHA1/SHA256 hash over all EAP-AKA/Identity packets. */
    519 	addr = wpabuf_head(data->id_msgs);
    520 	len = wpabuf_len(data->id_msgs);
    521 #ifdef EAP_AKA_PRIME
    522 	if (data->eap_method == EAP_TYPE_AKA_PRIME)
    523 		sha256_vector(1, &addr, &len, hash);
    524 	else
    525 #endif /* EAP_AKA_PRIME */
    526 		sha1_vector(1, &addr, &len, hash);
    527 
    528 	if (os_memcmp_const(hash, checkcode, hash_len) != 0) {
    529 		wpa_printf(MSG_DEBUG, "EAP-AKA: Mismatch in AT_CHECKCODE");
    530 		return -1;
    531 	}
    532 
    533 	return 0;
    534 }
    535 
    536 
    537 static struct wpabuf * eap_aka_client_error(struct eap_aka_data *data, u8 id,
    538 					    int err)
    539 {
    540 	struct eap_sim_msg *msg;
    541 
    542 	eap_aka_state(data, FAILURE);
    543 	data->num_id_req = 0;
    544 	data->num_notification = 0;
    545 
    546 	wpa_printf(MSG_DEBUG, "EAP-AKA: Send Client-Error (error code %d)",
    547 		   err);
    548 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
    549 			       EAP_AKA_SUBTYPE_CLIENT_ERROR);
    550 	eap_sim_msg_add(msg, EAP_SIM_AT_CLIENT_ERROR_CODE, err, NULL, 0);
    551 	return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
    552 }
    553 
    554 
    555 static struct wpabuf * eap_aka_authentication_reject(struct eap_aka_data *data,
    556 						     u8 id)
    557 {
    558 	struct eap_sim_msg *msg;
    559 
    560 	eap_aka_state(data, FAILURE);
    561 	data->num_id_req = 0;
    562 	data->num_notification = 0;
    563 
    564 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Authentication-Reject "
    565 		   "(id=%d)", id);
    566 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
    567 			       EAP_AKA_SUBTYPE_AUTHENTICATION_REJECT);
    568 	return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
    569 }
    570 
    571 
    572 static struct wpabuf * eap_aka_synchronization_failure(
    573 	struct eap_aka_data *data, u8 id)
    574 {
    575 	struct eap_sim_msg *msg;
    576 
    577 	data->num_id_req = 0;
    578 	data->num_notification = 0;
    579 
    580 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Synchronization-Failure "
    581 		   "(id=%d)", id);
    582 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
    583 			       EAP_AKA_SUBTYPE_SYNCHRONIZATION_FAILURE);
    584 	wpa_printf(MSG_DEBUG, "   AT_AUTS");
    585 	eap_sim_msg_add_full(msg, EAP_SIM_AT_AUTS, data->auts,
    586 			     EAP_AKA_AUTS_LEN);
    587 	return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
    588 }
    589 
    590 
    591 static struct wpabuf * eap_aka_response_identity(struct eap_sm *sm,
    592 						 struct eap_aka_data *data,
    593 						 u8 id,
    594 						 enum eap_sim_id_req id_req)
    595 {
    596 	const u8 *identity = NULL;
    597 	size_t identity_len = 0;
    598 	struct eap_sim_msg *msg;
    599 
    600 	data->reauth = 0;
    601 	if (id_req == ANY_ID && data->reauth_id) {
    602 		identity = data->reauth_id;
    603 		identity_len = data->reauth_id_len;
    604 		data->reauth = 1;
    605 	} else if ((id_req == ANY_ID || id_req == FULLAUTH_ID) &&
    606 		   data->pseudonym) {
    607 		identity = data->pseudonym;
    608 		identity_len = data->pseudonym_len;
    609 		eap_aka_clear_identities(sm, data, CLEAR_REAUTH_ID);
    610 	} else if (id_req != NO_ID_REQ) {
    611 		identity = eap_get_config_identity(sm, &identity_len);
    612 		if (identity) {
    613 			eap_aka_clear_identities(sm, data, CLEAR_PSEUDONYM |
    614 						 CLEAR_REAUTH_ID);
    615 		}
    616 	}
    617 	if (id_req != NO_ID_REQ)
    618 		eap_aka_clear_identities(sm, data, CLEAR_EAP_ID);
    619 
    620 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Identity (id=%d)", id);
    621 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
    622 			       EAP_AKA_SUBTYPE_IDENTITY);
    623 
    624 	if (identity) {
    625 		wpa_hexdump_ascii(MSG_DEBUG, "   AT_IDENTITY",
    626 				  identity, identity_len);
    627 		eap_sim_msg_add(msg, EAP_SIM_AT_IDENTITY, identity_len,
    628 				identity, identity_len);
    629 	}
    630 
    631 	return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
    632 }
    633 
    634 
    635 static struct wpabuf * eap_aka_response_challenge(struct eap_aka_data *data,
    636 						  u8 id)
    637 {
    638 	struct eap_sim_msg *msg;
    639 
    640 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Challenge (id=%d)", id);
    641 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
    642 			       EAP_AKA_SUBTYPE_CHALLENGE);
    643 	wpa_printf(MSG_DEBUG, "   AT_RES");
    644 	eap_sim_msg_add(msg, EAP_SIM_AT_RES, data->res_len * 8,
    645 			data->res, data->res_len);
    646 	eap_aka_add_checkcode(data, msg);
    647 	if (data->use_result_ind) {
    648 		wpa_printf(MSG_DEBUG, "   AT_RESULT_IND");
    649 		eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
    650 	}
    651 	wpa_printf(MSG_DEBUG, "   AT_MAC");
    652 	eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
    653 	return eap_sim_msg_finish(msg, data->eap_method, data->k_aut, (u8 *) "",
    654 				  0);
    655 }
    656 
    657 
    658 static struct wpabuf * eap_aka_response_reauth(struct eap_aka_data *data,
    659 					       u8 id, int counter_too_small,
    660 					       const u8 *nonce_s)
    661 {
    662 	struct eap_sim_msg *msg;
    663 	unsigned int counter;
    664 
    665 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Reauthentication (id=%d)",
    666 		   id);
    667 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
    668 			       EAP_AKA_SUBTYPE_REAUTHENTICATION);
    669 	wpa_printf(MSG_DEBUG, "   AT_IV");
    670 	wpa_printf(MSG_DEBUG, "   AT_ENCR_DATA");
    671 	eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV, EAP_SIM_AT_ENCR_DATA);
    672 
    673 	if (counter_too_small) {
    674 		wpa_printf(MSG_DEBUG, "   *AT_COUNTER_TOO_SMALL");
    675 		eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER_TOO_SMALL, 0, NULL, 0);
    676 		counter = data->counter_too_small;
    677 	} else
    678 		counter = data->counter;
    679 
    680 	wpa_printf(MSG_DEBUG, "   *AT_COUNTER %d", counter);
    681 	eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, counter, NULL, 0);
    682 
    683 	if (eap_sim_msg_add_encr_end(msg, data->k_encr, EAP_SIM_AT_PADDING)) {
    684 		wpa_printf(MSG_WARNING, "EAP-AKA: Failed to encrypt "
    685 			   "AT_ENCR_DATA");
    686 		eap_sim_msg_free(msg);
    687 		return NULL;
    688 	}
    689 	eap_aka_add_checkcode(data, msg);
    690 	if (data->use_result_ind) {
    691 		wpa_printf(MSG_DEBUG, "   AT_RESULT_IND");
    692 		eap_sim_msg_add(msg, EAP_SIM_AT_RESULT_IND, 0, NULL, 0);
    693 	}
    694 	wpa_printf(MSG_DEBUG, "   AT_MAC");
    695 	eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
    696 	return eap_sim_msg_finish(msg, data->eap_method, data->k_aut, nonce_s,
    697 				  EAP_SIM_NONCE_S_LEN);
    698 }
    699 
    700 
    701 static struct wpabuf * eap_aka_response_notification(struct eap_aka_data *data,
    702 						     u8 id, u16 notification)
    703 {
    704 	struct eap_sim_msg *msg;
    705 	u8 *k_aut = (notification & 0x4000) == 0 ? data->k_aut : NULL;
    706 
    707 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Notification (id=%d)", id);
    708 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
    709 			       EAP_AKA_SUBTYPE_NOTIFICATION);
    710 	if (k_aut && data->reauth) {
    711 		wpa_printf(MSG_DEBUG, "   AT_IV");
    712 		wpa_printf(MSG_DEBUG, "   AT_ENCR_DATA");
    713 		eap_sim_msg_add_encr_start(msg, EAP_SIM_AT_IV,
    714 					   EAP_SIM_AT_ENCR_DATA);
    715 		wpa_printf(MSG_DEBUG, "   *AT_COUNTER %d", data->counter);
    716 		eap_sim_msg_add(msg, EAP_SIM_AT_COUNTER, data->counter,
    717 				NULL, 0);
    718 		if (eap_sim_msg_add_encr_end(msg, data->k_encr,
    719 					     EAP_SIM_AT_PADDING)) {
    720 			wpa_printf(MSG_WARNING, "EAP-AKA: Failed to encrypt "
    721 				   "AT_ENCR_DATA");
    722 			eap_sim_msg_free(msg);
    723 			return NULL;
    724 		}
    725 	}
    726 	if (k_aut) {
    727 		wpa_printf(MSG_DEBUG, "   AT_MAC");
    728 		eap_sim_msg_add_mac(msg, EAP_SIM_AT_MAC);
    729 	}
    730 	return eap_sim_msg_finish(msg, data->eap_method, k_aut, (u8 *) "", 0);
    731 }
    732 
    733 
    734 static struct wpabuf * eap_aka_process_identity(struct eap_sm *sm,
    735 						struct eap_aka_data *data,
    736 						u8 id,
    737 						const struct wpabuf *reqData,
    738 						struct eap_sim_attrs *attr)
    739 {
    740 	int id_error;
    741 	struct wpabuf *buf;
    742 
    743 	wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Identity");
    744 
    745 	id_error = 0;
    746 	switch (attr->id_req) {
    747 	case NO_ID_REQ:
    748 		break;
    749 	case ANY_ID:
    750 		if (data->num_id_req > 0)
    751 			id_error++;
    752 		data->num_id_req++;
    753 		break;
    754 	case FULLAUTH_ID:
    755 		if (data->num_id_req > 1)
    756 			id_error++;
    757 		data->num_id_req++;
    758 		break;
    759 	case PERMANENT_ID:
    760 		if (data->num_id_req > 2)
    761 			id_error++;
    762 		data->num_id_req++;
    763 		break;
    764 	}
    765 	if (id_error) {
    766 		wpa_printf(MSG_INFO, "EAP-AKA: Too many ID requests "
    767 			   "used within one authentication");
    768 		return eap_aka_client_error(data, id,
    769 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
    770 	}
    771 
    772 	buf = eap_aka_response_identity(sm, data, id, attr->id_req);
    773 
    774 	if (data->prev_id != id) {
    775 		eap_aka_add_id_msg(data, reqData);
    776 		eap_aka_add_id_msg(data, buf);
    777 		data->prev_id = id;
    778 	}
    779 
    780 	return buf;
    781 }
    782 
    783 
    784 static int eap_aka_verify_mac(struct eap_aka_data *data,
    785 			      const struct wpabuf *req,
    786 			      const u8 *mac, const u8 *extra,
    787 			      size_t extra_len)
    788 {
    789 	if (data->eap_method == EAP_TYPE_AKA_PRIME)
    790 		return eap_sim_verify_mac_sha256(data->k_aut, req, mac, extra,
    791 						 extra_len);
    792 	return eap_sim_verify_mac(data->k_aut, req, mac, extra, extra_len);
    793 }
    794 
    795 
    796 #ifdef EAP_AKA_PRIME
    797 static struct wpabuf * eap_aka_prime_kdf_select(struct eap_aka_data *data,
    798 						u8 id, u16 kdf)
    799 {
    800 	struct eap_sim_msg *msg;
    801 
    802 	data->kdf_negotiation = 1;
    803 	data->kdf = kdf;
    804 	wpa_printf(MSG_DEBUG, "Generating EAP-AKA Challenge (id=%d) (KDF "
    805 		   "select)", id);
    806 	msg = eap_sim_msg_init(EAP_CODE_RESPONSE, id, data->eap_method,
    807 			       EAP_AKA_SUBTYPE_CHALLENGE);
    808 	wpa_printf(MSG_DEBUG, "   AT_KDF");
    809 	eap_sim_msg_add(msg, EAP_SIM_AT_KDF, kdf, NULL, 0);
    810 	return eap_sim_msg_finish(msg, data->eap_method, NULL, NULL, 0);
    811 }
    812 
    813 
    814 static struct wpabuf * eap_aka_prime_kdf_neg(struct eap_aka_data *data,
    815 					     u8 id, struct eap_sim_attrs *attr)
    816 {
    817 	size_t i;
    818 
    819 	for (i = 0; i < attr->kdf_count; i++) {
    820 		if (attr->kdf[i] == EAP_AKA_PRIME_KDF)
    821 			return eap_aka_prime_kdf_select(data, id,
    822 							EAP_AKA_PRIME_KDF);
    823 	}
    824 
    825 	/* No matching KDF found - fail authentication as if AUTN had been
    826 	 * incorrect */
    827 	return eap_aka_authentication_reject(data, id);
    828 }
    829 
    830 
    831 static int eap_aka_prime_kdf_valid(struct eap_aka_data *data,
    832 				   struct eap_sim_attrs *attr)
    833 {
    834 	size_t i, j;
    835 
    836 	if (attr->kdf_count == 0)
    837 		return 0;
    838 
    839 	/* The only allowed (and required) duplication of a KDF is the addition
    840 	 * of the selected KDF into the beginning of the list. */
    841 
    842 	if (data->kdf_negotiation) {
    843 		if (attr->kdf[0] != data->kdf) {
    844 			wpa_printf(MSG_WARNING, "EAP-AKA': The server did not "
    845 				   "accept the selected KDF");
    846 			return 0;
    847 		}
    848 
    849 		for (i = 1; i < attr->kdf_count; i++) {
    850 			if (attr->kdf[i] == data->kdf)
    851 				break;
    852 		}
    853 		if (i == attr->kdf_count &&
    854 		    attr->kdf_count < EAP_AKA_PRIME_KDF_MAX) {
    855 			wpa_printf(MSG_WARNING, "EAP-AKA': The server did not "
    856 				   "duplicate the selected KDF");
    857 			return 0;
    858 		}
    859 
    860 		/* TODO: should check that the list is identical to the one
    861 		 * used in the previous Challenge message apart from the added
    862 		 * entry in the beginning. */
    863 	}
    864 
    865 	for (i = data->kdf ? 1 : 0; i < attr->kdf_count; i++) {
    866 		for (j = i + 1; j < attr->kdf_count; j++) {
    867 			if (attr->kdf[i] == attr->kdf[j]) {
    868 				wpa_printf(MSG_WARNING, "EAP-AKA': The server "
    869 					   "included a duplicated KDF");
    870 				return 0;
    871 			}
    872 		}
    873 	}
    874 
    875 	return 1;
    876 }
    877 #endif /* EAP_AKA_PRIME */
    878 
    879 
    880 static struct wpabuf * eap_aka_process_challenge(struct eap_sm *sm,
    881 						 struct eap_aka_data *data,
    882 						 u8 id,
    883 						 const struct wpabuf *reqData,
    884 						 struct eap_sim_attrs *attr)
    885 {
    886 	const u8 *identity;
    887 	size_t identity_len;
    888 	int res;
    889 	struct eap_sim_attrs eattr;
    890 
    891 	wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Challenge");
    892 
    893 	if (attr->checkcode &&
    894 	    eap_aka_verify_checkcode(data, attr->checkcode,
    895 				     attr->checkcode_len)) {
    896 		wpa_printf(MSG_WARNING, "EAP-AKA: Invalid AT_CHECKCODE in the "
    897 			   "message");
    898 		return eap_aka_client_error(data, id,
    899 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
    900 	}
    901 
    902 #ifdef EAP_AKA_PRIME
    903 	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
    904 		if (!attr->kdf_input || attr->kdf_input_len == 0) {
    905 			wpa_printf(MSG_WARNING, "EAP-AKA': Challenge message "
    906 				   "did not include non-empty AT_KDF_INPUT");
    907 			/* Fail authentication as if AUTN had been incorrect */
    908 			return eap_aka_authentication_reject(data, id);
    909 		}
    910 		os_free(data->network_name);
    911 		data->network_name = os_malloc(attr->kdf_input_len);
    912 		if (data->network_name == NULL) {
    913 			wpa_printf(MSG_WARNING, "EAP-AKA': No memory for "
    914 				   "storing Network Name");
    915 			return eap_aka_authentication_reject(data, id);
    916 		}
    917 		os_memcpy(data->network_name, attr->kdf_input,
    918 			  attr->kdf_input_len);
    919 		data->network_name_len = attr->kdf_input_len;
    920 		wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA': Network Name "
    921 				  "(AT_KDF_INPUT)",
    922 				  data->network_name, data->network_name_len);
    923 		/* TODO: check Network Name per 3GPP.33.402 */
    924 
    925 		if (!eap_aka_prime_kdf_valid(data, attr))
    926 			return eap_aka_authentication_reject(data, id);
    927 
    928 		if (attr->kdf[0] != EAP_AKA_PRIME_KDF)
    929 			return eap_aka_prime_kdf_neg(data, id, attr);
    930 
    931 		data->kdf = EAP_AKA_PRIME_KDF;
    932 		wpa_printf(MSG_DEBUG, "EAP-AKA': KDF %d selected", data->kdf);
    933 	}
    934 
    935 	if (data->eap_method == EAP_TYPE_AKA && attr->bidding) {
    936 		u16 flags = WPA_GET_BE16(attr->bidding);
    937 		if ((flags & EAP_AKA_BIDDING_FLAG_D) &&
    938 		    eap_allowed_method(sm, EAP_VENDOR_IETF,
    939 				       EAP_TYPE_AKA_PRIME)) {
    940 			wpa_printf(MSG_WARNING, "EAP-AKA: Bidding down from "
    941 				   "AKA' to AKA detected");
    942 			/* Fail authentication as if AUTN had been incorrect */
    943 			return eap_aka_authentication_reject(data, id);
    944 		}
    945 	}
    946 #endif /* EAP_AKA_PRIME */
    947 
    948 	data->reauth = 0;
    949 	if (!attr->mac || !attr->rand || !attr->autn) {
    950 		wpa_printf(MSG_WARNING, "EAP-AKA: Challenge message "
    951 			   "did not include%s%s%s",
    952 			   !attr->mac ? " AT_MAC" : "",
    953 			   !attr->rand ? " AT_RAND" : "",
    954 			   !attr->autn ? " AT_AUTN" : "");
    955 		return eap_aka_client_error(data, id,
    956 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
    957 	}
    958 	os_memcpy(data->rand, attr->rand, EAP_AKA_RAND_LEN);
    959 	os_memcpy(data->autn, attr->autn, EAP_AKA_AUTN_LEN);
    960 
    961 	res = eap_aka_umts_auth(sm, data);
    962 	if (res == -1) {
    963 		wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication "
    964 			   "failed (AUTN)");
    965 		return eap_aka_authentication_reject(data, id);
    966 	} else if (res == -2) {
    967 		wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication "
    968 			   "failed (AUTN seq# -> AUTS)");
    969 		return eap_aka_synchronization_failure(data, id);
    970 	} else if (res > 0) {
    971 		wpa_printf(MSG_DEBUG, "EAP-AKA: Wait for external USIM processing");
    972 		return NULL;
    973 	} else if (res) {
    974 		wpa_printf(MSG_WARNING, "EAP-AKA: UMTS authentication failed");
    975 		return eap_aka_client_error(data, id,
    976 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
    977 	}
    978 #ifdef EAP_AKA_PRIME
    979 	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
    980 		/* Note: AUTN = (SQN ^ AK) || AMF || MAC which gives us the
    981 		 * needed 6-octet SQN ^ AK for CK',IK' derivation */
    982 		u16 amf = WPA_GET_BE16(data->autn + 6);
    983 		if (!(amf & 0x8000)) {
    984 			wpa_printf(MSG_WARNING, "EAP-AKA': AMF separation bit "
    985 				   "not set (AMF=0x%4x)", amf);
    986 			return eap_aka_authentication_reject(data, id);
    987 		}
    988 		eap_aka_prime_derive_ck_ik_prime(data->ck, data->ik,
    989 						 data->autn,
    990 						 data->network_name,
    991 						 data->network_name_len);
    992 	}
    993 #endif /* EAP_AKA_PRIME */
    994 	if (data->last_eap_identity) {
    995 		identity = data->last_eap_identity;
    996 		identity_len = data->last_eap_identity_len;
    997 	} else if (data->pseudonym) {
    998 		identity = data->pseudonym;
    999 		identity_len = data->pseudonym_len;
   1000 	} else
   1001 		identity = eap_get_config_identity(sm, &identity_len);
   1002 	wpa_hexdump_ascii(MSG_DEBUG, "EAP-AKA: Selected identity for MK "
   1003 			  "derivation", identity, identity_len);
   1004 	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
   1005 		eap_aka_prime_derive_keys(identity, identity_len, data->ik,
   1006 					  data->ck, data->k_encr, data->k_aut,
   1007 					  data->k_re, data->msk, data->emsk);
   1008 	} else {
   1009 		eap_aka_derive_mk(identity, identity_len, data->ik, data->ck,
   1010 				  data->mk);
   1011 		eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut,
   1012 				    data->msk, data->emsk);
   1013 	}
   1014 	if (eap_aka_verify_mac(data, reqData, attr->mac, (u8 *) "", 0)) {
   1015 		wpa_printf(MSG_WARNING, "EAP-AKA: Challenge message "
   1016 			   "used invalid AT_MAC");
   1017 		return eap_aka_client_error(data, id,
   1018 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
   1019 	}
   1020 
   1021 	/* Old reauthentication identity must not be used anymore. In
   1022 	 * other words, if no new identities are received, full
   1023 	 * authentication will be used on next reauthentication (using
   1024 	 * pseudonym identity or permanent identity). */
   1025 	eap_aka_clear_identities(sm, data, CLEAR_REAUTH_ID | CLEAR_EAP_ID);
   1026 
   1027 	if (attr->encr_data) {
   1028 		u8 *decrypted;
   1029 		decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
   1030 					       attr->encr_data_len, attr->iv,
   1031 					       &eattr, 0);
   1032 		if (decrypted == NULL) {
   1033 			return eap_aka_client_error(
   1034 				data, id, EAP_AKA_UNABLE_TO_PROCESS_PACKET);
   1035 		}
   1036 		eap_aka_learn_ids(sm, data, &eattr);
   1037 		os_free(decrypted);
   1038 	}
   1039 
   1040 	if (data->result_ind && attr->result_ind)
   1041 		data->use_result_ind = 1;
   1042 
   1043 	if (data->state != FAILURE) {
   1044 		eap_aka_state(data, data->use_result_ind ?
   1045 			      RESULT_SUCCESS : SUCCESS);
   1046 	}
   1047 
   1048 	data->num_id_req = 0;
   1049 	data->num_notification = 0;
   1050 	/* RFC 4187 specifies that counter is initialized to one after
   1051 	 * fullauth, but initializing it to zero makes it easier to implement
   1052 	 * reauth verification. */
   1053 	data->counter = 0;
   1054 	return eap_aka_response_challenge(data, id);
   1055 }
   1056 
   1057 
   1058 static int eap_aka_process_notification_reauth(struct eap_aka_data *data,
   1059 					       struct eap_sim_attrs *attr)
   1060 {
   1061 	struct eap_sim_attrs eattr;
   1062 	u8 *decrypted;
   1063 
   1064 	if (attr->encr_data == NULL || attr->iv == NULL) {
   1065 		wpa_printf(MSG_WARNING, "EAP-AKA: Notification message after "
   1066 			   "reauth did not include encrypted data");
   1067 		return -1;
   1068 	}
   1069 
   1070 	decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
   1071 				       attr->encr_data_len, attr->iv, &eattr,
   1072 				       0);
   1073 	if (decrypted == NULL) {
   1074 		wpa_printf(MSG_WARNING, "EAP-AKA: Failed to parse encrypted "
   1075 			   "data from notification message");
   1076 		return -1;
   1077 	}
   1078 
   1079 	if (eattr.counter < 0 || (size_t) eattr.counter != data->counter) {
   1080 		wpa_printf(MSG_WARNING, "EAP-AKA: Counter in notification "
   1081 			   "message does not match with counter in reauth "
   1082 			   "message");
   1083 		os_free(decrypted);
   1084 		return -1;
   1085 	}
   1086 
   1087 	os_free(decrypted);
   1088 	return 0;
   1089 }
   1090 
   1091 
   1092 static int eap_aka_process_notification_auth(struct eap_aka_data *data,
   1093 					     const struct wpabuf *reqData,
   1094 					     struct eap_sim_attrs *attr)
   1095 {
   1096 	if (attr->mac == NULL) {
   1097 		wpa_printf(MSG_INFO, "EAP-AKA: no AT_MAC in after_auth "
   1098 			   "Notification message");
   1099 		return -1;
   1100 	}
   1101 
   1102 	if (eap_aka_verify_mac(data, reqData, attr->mac, (u8 *) "", 0)) {
   1103 		wpa_printf(MSG_WARNING, "EAP-AKA: Notification message "
   1104 			   "used invalid AT_MAC");
   1105 		return -1;
   1106 	}
   1107 
   1108 	if (data->reauth &&
   1109 	    eap_aka_process_notification_reauth(data, attr)) {
   1110 		wpa_printf(MSG_WARNING, "EAP-AKA: Invalid notification "
   1111 			   "message after reauth");
   1112 		return -1;
   1113 	}
   1114 
   1115 	return 0;
   1116 }
   1117 
   1118 
   1119 static struct wpabuf * eap_aka_process_notification(
   1120 	struct eap_sm *sm, struct eap_aka_data *data, u8 id,
   1121 	const struct wpabuf *reqData, struct eap_sim_attrs *attr)
   1122 {
   1123 	wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Notification");
   1124 	if (data->num_notification > 0) {
   1125 		wpa_printf(MSG_INFO, "EAP-AKA: too many notification "
   1126 			   "rounds (only one allowed)");
   1127 		return eap_aka_client_error(data, id,
   1128 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
   1129 	}
   1130 	data->num_notification++;
   1131 	if (attr->notification == -1) {
   1132 		wpa_printf(MSG_INFO, "EAP-AKA: no AT_NOTIFICATION in "
   1133 			   "Notification message");
   1134 		return eap_aka_client_error(data, id,
   1135 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
   1136 	}
   1137 
   1138 	if ((attr->notification & 0x4000) == 0 &&
   1139 	    eap_aka_process_notification_auth(data, reqData, attr)) {
   1140 		return eap_aka_client_error(data, id,
   1141 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
   1142 	}
   1143 
   1144 	eap_sim_report_notification(sm->msg_ctx, attr->notification, 1);
   1145 	if (attr->notification >= 0 && attr->notification < 32768) {
   1146 		eap_aka_state(data, FAILURE);
   1147 	} else if (attr->notification == EAP_SIM_SUCCESS &&
   1148 		   data->state == RESULT_SUCCESS)
   1149 		eap_aka_state(data, SUCCESS);
   1150 	return eap_aka_response_notification(data, id, attr->notification);
   1151 }
   1152 
   1153 
   1154 static struct wpabuf * eap_aka_process_reauthentication(
   1155 	struct eap_sm *sm, struct eap_aka_data *data, u8 id,
   1156 	const struct wpabuf *reqData, struct eap_sim_attrs *attr)
   1157 {
   1158 	struct eap_sim_attrs eattr;
   1159 	u8 *decrypted;
   1160 
   1161 	wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Reauthentication");
   1162 
   1163 	if (attr->checkcode &&
   1164 	    eap_aka_verify_checkcode(data, attr->checkcode,
   1165 				     attr->checkcode_len)) {
   1166 		wpa_printf(MSG_WARNING, "EAP-AKA: Invalid AT_CHECKCODE in the "
   1167 			   "message");
   1168 		return eap_aka_client_error(data, id,
   1169 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
   1170 	}
   1171 
   1172 	if (data->reauth_id == NULL) {
   1173 		wpa_printf(MSG_WARNING, "EAP-AKA: Server is trying "
   1174 			   "reauthentication, but no reauth_id available");
   1175 		return eap_aka_client_error(data, id,
   1176 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
   1177 	}
   1178 
   1179 	data->reauth = 1;
   1180 	if (eap_aka_verify_mac(data, reqData, attr->mac, (u8 *) "", 0)) {
   1181 		wpa_printf(MSG_WARNING, "EAP-AKA: Reauthentication "
   1182 			   "did not have valid AT_MAC");
   1183 		return eap_aka_client_error(data, id,
   1184 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
   1185 	}
   1186 
   1187 	if (attr->encr_data == NULL || attr->iv == NULL) {
   1188 		wpa_printf(MSG_WARNING, "EAP-AKA: Reauthentication "
   1189 			   "message did not include encrypted data");
   1190 		return eap_aka_client_error(data, id,
   1191 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
   1192 	}
   1193 
   1194 	decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
   1195 				       attr->encr_data_len, attr->iv, &eattr,
   1196 				       0);
   1197 	if (decrypted == NULL) {
   1198 		wpa_printf(MSG_WARNING, "EAP-AKA: Failed to parse encrypted "
   1199 			   "data from reauthentication message");
   1200 		return eap_aka_client_error(data, id,
   1201 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
   1202 	}
   1203 
   1204 	if (eattr.nonce_s == NULL || eattr.counter < 0) {
   1205 		wpa_printf(MSG_INFO, "EAP-AKA: (encr) No%s%s in reauth packet",
   1206 			   !eattr.nonce_s ? " AT_NONCE_S" : "",
   1207 			   eattr.counter < 0 ? " AT_COUNTER" : "");
   1208 		os_free(decrypted);
   1209 		return eap_aka_client_error(data, id,
   1210 					    EAP_AKA_UNABLE_TO_PROCESS_PACKET);
   1211 	}
   1212 
   1213 	if (eattr.counter < 0 || (size_t) eattr.counter <= data->counter) {
   1214 		struct wpabuf *res;
   1215 		wpa_printf(MSG_INFO, "EAP-AKA: (encr) Invalid counter "
   1216 			   "(%d <= %d)", eattr.counter, data->counter);
   1217 		data->counter_too_small = eattr.counter;
   1218 
   1219 		/* Reply using Re-auth w/ AT_COUNTER_TOO_SMALL. The current
   1220 		 * reauth_id must not be used to start a new reauthentication.
   1221 		 * However, since it was used in the last EAP-Response-Identity
   1222 		 * packet, it has to saved for the following fullauth to be
   1223 		 * used in MK derivation. */
   1224 		os_free(data->last_eap_identity);
   1225 		data->last_eap_identity = data->reauth_id;
   1226 		data->last_eap_identity_len = data->reauth_id_len;
   1227 		data->reauth_id = NULL;
   1228 		data->reauth_id_len = 0;
   1229 
   1230 		res = eap_aka_response_reauth(data, id, 1, eattr.nonce_s);
   1231 		os_free(decrypted);
   1232 
   1233 		return res;
   1234 	}
   1235 	data->counter = eattr.counter;
   1236 
   1237 	os_memcpy(data->nonce_s, eattr.nonce_s, EAP_SIM_NONCE_S_LEN);
   1238 	wpa_hexdump(MSG_DEBUG, "EAP-AKA: (encr) AT_NONCE_S",
   1239 		    data->nonce_s, EAP_SIM_NONCE_S_LEN);
   1240 
   1241 	if (data->eap_method == EAP_TYPE_AKA_PRIME) {
   1242 		eap_aka_prime_derive_keys_reauth(data->k_re, data->counter,
   1243 						 data->reauth_id,
   1244 						 data->reauth_id_len,
   1245 						 data->nonce_s,
   1246 						 data->msk, data->emsk);
   1247 	} else {
   1248 		eap_sim_derive_keys_reauth(data->counter, data->reauth_id,
   1249 					   data->reauth_id_len,
   1250 					   data->nonce_s, data->mk,
   1251 					   data->msk, data->emsk);
   1252 	}
   1253 	eap_aka_clear_identities(sm, data, CLEAR_REAUTH_ID | CLEAR_EAP_ID);
   1254 	eap_aka_learn_ids(sm, data, &eattr);
   1255 
   1256 	if (data->result_ind && attr->result_ind)
   1257 		data->use_result_ind = 1;
   1258 
   1259 	if (data->state != FAILURE) {
   1260 		eap_aka_state(data, data->use_result_ind ?
   1261 			      RESULT_SUCCESS : SUCCESS);
   1262 	}
   1263 
   1264 	data->num_id_req = 0;
   1265 	data->num_notification = 0;
   1266 	if (data->counter > EAP_AKA_MAX_FAST_REAUTHS) {
   1267 		wpa_printf(MSG_DEBUG, "EAP-AKA: Maximum number of "
   1268 			   "fast reauths performed - force fullauth");
   1269 		eap_aka_clear_identities(sm, data,
   1270 					 CLEAR_REAUTH_ID | CLEAR_EAP_ID);
   1271 	}
   1272 	os_free(decrypted);
   1273 	return eap_aka_response_reauth(data, id, 0, data->nonce_s);
   1274 }
   1275 
   1276 
   1277 static struct wpabuf * eap_aka_process(struct eap_sm *sm, void *priv,
   1278 				       struct eap_method_ret *ret,
   1279 				       const struct wpabuf *reqData)
   1280 {
   1281 	struct eap_aka_data *data = priv;
   1282 	const struct eap_hdr *req;
   1283 	u8 subtype, id;
   1284 	struct wpabuf *res;
   1285 	const u8 *pos;
   1286 	struct eap_sim_attrs attr;
   1287 	size_t len;
   1288 
   1289 	wpa_hexdump_buf(MSG_DEBUG, "EAP-AKA: EAP data", reqData);
   1290 	if (eap_get_config_identity(sm, &len) == NULL) {
   1291 		wpa_printf(MSG_INFO, "EAP-AKA: Identity not configured");
   1292 		eap_sm_request_identity(sm);
   1293 		ret->ignore = TRUE;
   1294 		return NULL;
   1295 	}
   1296 
   1297 	pos = eap_hdr_validate(EAP_VENDOR_IETF, data->eap_method, reqData,
   1298 			       &len);
   1299 	if (pos == NULL || len < 3) {
   1300 		ret->ignore = TRUE;
   1301 		return NULL;
   1302 	}
   1303 	req = wpabuf_head(reqData);
   1304 	id = req->identifier;
   1305 	len = be_to_host16(req->length);
   1306 
   1307 	ret->ignore = FALSE;
   1308 	ret->methodState = METHOD_MAY_CONT;
   1309 	ret->decision = DECISION_FAIL;
   1310 	ret->allowNotifications = TRUE;
   1311 
   1312 	subtype = *pos++;
   1313 	wpa_printf(MSG_DEBUG, "EAP-AKA: Subtype=%d", subtype);
   1314 	pos += 2; /* Reserved */
   1315 
   1316 	if (eap_sim_parse_attr(pos, wpabuf_head_u8(reqData) + len, &attr,
   1317 			       data->eap_method == EAP_TYPE_AKA_PRIME ? 2 : 1,
   1318 			       0)) {
   1319 		res = eap_aka_client_error(data, id,
   1320 					   EAP_AKA_UNABLE_TO_PROCESS_PACKET);
   1321 		goto done;
   1322 	}
   1323 
   1324 	switch (subtype) {
   1325 	case EAP_AKA_SUBTYPE_IDENTITY:
   1326 		res = eap_aka_process_identity(sm, data, id, reqData, &attr);
   1327 		break;
   1328 	case EAP_AKA_SUBTYPE_CHALLENGE:
   1329 		res = eap_aka_process_challenge(sm, data, id, reqData, &attr);
   1330 		break;
   1331 	case EAP_AKA_SUBTYPE_NOTIFICATION:
   1332 		res = eap_aka_process_notification(sm, data, id, reqData,
   1333 						   &attr);
   1334 		break;
   1335 	case EAP_AKA_SUBTYPE_REAUTHENTICATION:
   1336 		res = eap_aka_process_reauthentication(sm, data, id, reqData,
   1337 						       &attr);
   1338 		break;
   1339 	case EAP_AKA_SUBTYPE_CLIENT_ERROR:
   1340 		wpa_printf(MSG_DEBUG, "EAP-AKA: subtype Client-Error");
   1341 		res = eap_aka_client_error(data, id,
   1342 					   EAP_AKA_UNABLE_TO_PROCESS_PACKET);
   1343 		break;
   1344 	default:
   1345 		wpa_printf(MSG_DEBUG, "EAP-AKA: Unknown subtype=%d", subtype);
   1346 		res = eap_aka_client_error(data, id,
   1347 					   EAP_AKA_UNABLE_TO_PROCESS_PACKET);
   1348 		break;
   1349 	}
   1350 
   1351 done:
   1352 	if (data->state == FAILURE) {
   1353 		ret->decision = DECISION_FAIL;
   1354 		ret->methodState = METHOD_DONE;
   1355 	} else if (data->state == SUCCESS) {
   1356 		ret->decision = data->use_result_ind ?
   1357 			DECISION_UNCOND_SUCC : DECISION_COND_SUCC;
   1358 		/*
   1359 		 * It is possible for the server to reply with AKA
   1360 		 * Notification, so we must allow the method to continue and
   1361 		 * not only accept EAP-Success at this point.
   1362 		 */
   1363 		ret->methodState = data->use_result_ind ?
   1364 			METHOD_DONE : METHOD_MAY_CONT;
   1365 	} else if (data->state == RESULT_SUCCESS)
   1366 		ret->methodState = METHOD_CONT;
   1367 
   1368 	if (ret->methodState == METHOD_DONE) {
   1369 		ret->allowNotifications = FALSE;
   1370 	}
   1371 
   1372 	return res;
   1373 }
   1374 
   1375 
   1376 static Boolean eap_aka_has_reauth_data(struct eap_sm *sm, void *priv)
   1377 {
   1378 	struct eap_aka_data *data = priv;
   1379 	return data->pseudonym || data->reauth_id;
   1380 }
   1381 
   1382 
   1383 static void eap_aka_deinit_for_reauth(struct eap_sm *sm, void *priv)
   1384 {
   1385 	struct eap_aka_data *data = priv;
   1386 	eap_aka_clear_identities(sm, data, CLEAR_EAP_ID);
   1387 	data->prev_id = -1;
   1388 	wpabuf_free(data->id_msgs);
   1389 	data->id_msgs = NULL;
   1390 	data->use_result_ind = 0;
   1391 	data->kdf_negotiation = 0;
   1392 	eap_aka_clear_keys(data, 1);
   1393 }
   1394 
   1395 
   1396 static void * eap_aka_init_for_reauth(struct eap_sm *sm, void *priv)
   1397 {
   1398 	struct eap_aka_data *data = priv;
   1399 	data->num_id_req = 0;
   1400 	data->num_notification = 0;
   1401 	eap_aka_state(data, CONTINUE);
   1402 	return priv;
   1403 }
   1404 
   1405 
   1406 static const u8 * eap_aka_get_identity(struct eap_sm *sm, void *priv,
   1407 				       size_t *len)
   1408 {
   1409 	struct eap_aka_data *data = priv;
   1410 
   1411 	if (data->reauth_id) {
   1412 		*len = data->reauth_id_len;
   1413 		return data->reauth_id;
   1414 	}
   1415 
   1416 	if (data->pseudonym) {
   1417 		*len = data->pseudonym_len;
   1418 		return data->pseudonym;
   1419 	}
   1420 
   1421 	return NULL;
   1422 }
   1423 
   1424 
   1425 static Boolean eap_aka_isKeyAvailable(struct eap_sm *sm, void *priv)
   1426 {
   1427 	struct eap_aka_data *data = priv;
   1428 	return data->state == SUCCESS;
   1429 }
   1430 
   1431 
   1432 static u8 * eap_aka_getKey(struct eap_sm *sm, void *priv, size_t *len)
   1433 {
   1434 	struct eap_aka_data *data = priv;
   1435 	u8 *key;
   1436 
   1437 	if (data->state != SUCCESS)
   1438 		return NULL;
   1439 
   1440 	key = os_malloc(EAP_SIM_KEYING_DATA_LEN);
   1441 	if (key == NULL)
   1442 		return NULL;
   1443 
   1444 	*len = EAP_SIM_KEYING_DATA_LEN;
   1445 	os_memcpy(key, data->msk, EAP_SIM_KEYING_DATA_LEN);
   1446 
   1447 	return key;
   1448 }
   1449 
   1450 
   1451 static u8 * eap_aka_get_session_id(struct eap_sm *sm, void *priv, size_t *len)
   1452 {
   1453 	struct eap_aka_data *data = priv;
   1454 	u8 *id;
   1455 
   1456 	if (data->state != SUCCESS)
   1457 		return NULL;
   1458 
   1459 	*len = 1 + EAP_AKA_RAND_LEN + EAP_AKA_AUTN_LEN;
   1460 	id = os_malloc(*len);
   1461 	if (id == NULL)
   1462 		return NULL;
   1463 
   1464 	id[0] = data->eap_method;
   1465 	os_memcpy(id + 1, data->rand, EAP_AKA_RAND_LEN);
   1466 	os_memcpy(id + 1 + EAP_AKA_RAND_LEN, data->autn, EAP_AKA_AUTN_LEN);
   1467 	wpa_hexdump(MSG_DEBUG, "EAP-AKA: Derived Session-Id", id, *len);
   1468 
   1469 	return id;
   1470 }
   1471 
   1472 
   1473 static u8 * eap_aka_get_emsk(struct eap_sm *sm, void *priv, size_t *len)
   1474 {
   1475 	struct eap_aka_data *data = priv;
   1476 	u8 *key;
   1477 
   1478 	if (data->state != SUCCESS)
   1479 		return NULL;
   1480 
   1481 	key = os_malloc(EAP_EMSK_LEN);
   1482 	if (key == NULL)
   1483 		return NULL;
   1484 
   1485 	*len = EAP_EMSK_LEN;
   1486 	os_memcpy(key, data->emsk, EAP_EMSK_LEN);
   1487 
   1488 	return key;
   1489 }
   1490 
   1491 
   1492 int eap_peer_aka_register(void)
   1493 {
   1494 	struct eap_method *eap;
   1495 
   1496 	eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
   1497 				    EAP_VENDOR_IETF, EAP_TYPE_AKA, "AKA");
   1498 	if (eap == NULL)
   1499 		return -1;
   1500 
   1501 	eap->init = eap_aka_init;
   1502 	eap->deinit = eap_aka_deinit;
   1503 	eap->process = eap_aka_process;
   1504 	eap->isKeyAvailable = eap_aka_isKeyAvailable;
   1505 	eap->getKey = eap_aka_getKey;
   1506 	eap->getSessionId = eap_aka_get_session_id;
   1507 	eap->has_reauth_data = eap_aka_has_reauth_data;
   1508 	eap->deinit_for_reauth = eap_aka_deinit_for_reauth;
   1509 	eap->init_for_reauth = eap_aka_init_for_reauth;
   1510 	eap->get_identity = eap_aka_get_identity;
   1511 	eap->get_emsk = eap_aka_get_emsk;
   1512 
   1513 	return eap_peer_method_register(eap);
   1514 }
   1515 
   1516 
   1517 #ifdef EAP_AKA_PRIME
   1518 int eap_peer_aka_prime_register(void)
   1519 {
   1520 	struct eap_method *eap;
   1521 
   1522 	eap = eap_peer_method_alloc(EAP_PEER_METHOD_INTERFACE_VERSION,
   1523 				    EAP_VENDOR_IETF, EAP_TYPE_AKA_PRIME,
   1524 				    "AKA'");
   1525 	if (eap == NULL)
   1526 		return -1;
   1527 
   1528 	eap->init = eap_aka_prime_init;
   1529 	eap->deinit = eap_aka_deinit;
   1530 	eap->process = eap_aka_process;
   1531 	eap->isKeyAvailable = eap_aka_isKeyAvailable;
   1532 	eap->getKey = eap_aka_getKey;
   1533 	eap->getSessionId = eap_aka_get_session_id;
   1534 	eap->has_reauth_data = eap_aka_has_reauth_data;
   1535 	eap->deinit_for_reauth = eap_aka_deinit_for_reauth;
   1536 	eap->init_for_reauth = eap_aka_init_for_reauth;
   1537 	eap->get_identity = eap_aka_get_identity;
   1538 	eap->get_emsk = eap_aka_get_emsk;
   1539 
   1540 	return eap_peer_method_register(eap);
   1541 }
   1542 #endif /* EAP_AKA_PRIME */
   1543