示例#1
0
static u8 * eap_sim_process_challenge(struct eap_sm *sm,
				      struct eap_sim_data *data,
				      struct eap_hdr *req, size_t reqDataLen,
				      size_t *respDataLen,
				      struct eap_sim_attrs *attr)
{
	struct wpa_ssid *config = eap_get_config(sm);
	u8 *identity;
	size_t identity_len;
	struct eap_sim_attrs eattr;

	wpa_printf(MSG_DEBUG, "EAP-SIM: subtype Challenge");
	data->reauth = 0;
	if (!attr->mac || !attr->rand) {
		wpa_printf(MSG_WARNING, "EAP-SIM: Challenge message "
			   "did not include%s%s",
			   !attr->mac ? " AT_MAC" : "",
			   !attr->rand ? " AT_RAND" : "");
		return eap_sim_client_error(sm, data, req, respDataLen,
					    EAP_SIM_UNABLE_TO_PROCESS_PACKET);
	}

	wpa_printf(MSG_DEBUG, "EAP-SIM: %lu challenges",
		   (unsigned long) attr->num_chal);
	if (attr->num_chal < data->min_num_chal) {
		wpa_printf(MSG_INFO, "EAP-SIM: Insufficient number of "
			   "challenges (%lu)", (unsigned long) attr->num_chal);
		return eap_sim_client_error(sm, data, req, respDataLen,
					    EAP_SIM_INSUFFICIENT_NUM_OF_CHAL);
	}
	if (attr->num_chal > 3) {
		wpa_printf(MSG_INFO, "EAP-SIM: Too many challenges "
			   "(%lu)", (unsigned long) attr->num_chal);
		return eap_sim_client_error(sm, data, req, respDataLen,
					    EAP_SIM_UNABLE_TO_PROCESS_PACKET);
	}

	/* Verify that RANDs are different */
	if (memcmp(attr->rand, attr->rand + GSM_RAND_LEN,
		   GSM_RAND_LEN) == 0 ||
	    (attr->num_chal > 2 &&
	     (memcmp(attr->rand, attr->rand + 2 * GSM_RAND_LEN,
		     GSM_RAND_LEN) == 0 ||
	      memcmp(attr->rand + GSM_RAND_LEN,
		     attr->rand + 2 * GSM_RAND_LEN,
		     GSM_RAND_LEN) == 0))) {
		wpa_printf(MSG_INFO, "EAP-SIM: Same RAND used multiple times");
		return eap_sim_client_error(sm, data, req, respDataLen,
					    EAP_SIM_RAND_NOT_FRESH);
	}

	memcpy(data->rand, attr->rand, attr->num_chal * GSM_RAND_LEN);
	data->num_chal = attr->num_chal;
		
	if (eap_sim_gsm_auth(sm, data)) {
		wpa_printf(MSG_WARNING, "EAP-SIM: GSM authentication failed");
		return eap_sim_client_error(sm, data, req, respDataLen,
					    EAP_SIM_UNABLE_TO_PROCESS_PACKET);
	}
	if (data->last_eap_identity) {
		identity = data->last_eap_identity;
		identity_len = data->last_eap_identity_len;
	} else if (data->pseudonym) {
		identity = data->pseudonym;
		identity_len = data->pseudonym_len;
	} else {
		identity = config->identity;
		identity_len = config->identity_len;
	}
	wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM: Selected identity for MK "
			  "derivation", identity, identity_len);
	eap_sim_derive_mk(data, identity, identity_len);
	eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut, data->msk);
	if (eap_sim_verify_mac(data->k_aut, (u8 *) req, reqDataLen, attr->mac,
			       data->nonce_mt, EAP_SIM_NONCE_MT_LEN)) {
		wpa_printf(MSG_WARNING, "EAP-SIM: Challenge message "
			   "used invalid AT_MAC");
		return eap_sim_client_error(sm, data, req, respDataLen,
					    EAP_SIM_UNABLE_TO_PROCESS_PACKET);
	}

	/* Old reauthentication and pseudonym identities must not be used
	 * anymore. In other words, if no new identities are received, full
	 * authentication will be used on next reauthentication. */
	eap_sim_clear_identities(data, CLEAR_PSEUDONYM | CLEAR_REAUTH_ID |
				 CLEAR_EAP_ID);

	if (attr->encr_data) {
		if (eap_sim_parse_encr(data->k_encr, attr->encr_data,
				       attr->encr_data_len, attr->iv, &eattr,
				       0)) {
			return eap_sim_client_error(
				sm, data, req, respDataLen,
				EAP_SIM_UNABLE_TO_PROCESS_PACKET);
		}
		eap_sim_learn_ids(data, &eattr);
	}

	if (data->state != FAILURE)
		data->state = SUCCESS;

	data->num_id_req = 0;
	data->num_notification = 0;
	/* draft-haverinen-pppext-eap-sim-13.txt specifies that counter
	 * is initialized to one after fullauth, but initializing it to
	 * zero makes it easier to implement reauth verification. */
	data->counter = 0;
	return eap_sim_response_challenge(sm, data, req, respDataLen);
}
示例#2
0
static struct wpabuf * eap_sim_process_challenge(struct eap_sm *sm,
						 struct eap_sim_data *data,
						 u8 id,
						 const struct wpabuf *reqData,
						 struct eap_sim_attrs *attr)
{
	const u8 *identity;
	size_t identity_len;
	struct eap_sim_attrs eattr;

	wpa_printf(MSG_DEBUG, "EAP-SIM: subtype Challenge");
	data->reauth = 0;
	if (!attr->mac || !attr->rand) {
		wpa_printf(MSG_WARNING, "EAP-SIM: Challenge message "
			   "did not include%s%s",
			   !attr->mac ? " AT_MAC" : "",
			   !attr->rand ? " AT_RAND" : "");
		return eap_sim_client_error(data, id,
					    EAP_SIM_UNABLE_TO_PROCESS_PACKET);
	}

	wpa_printf(MSG_DEBUG, "EAP-SIM: %lu challenges",
		   (unsigned long) attr->num_chal);
	if (attr->num_chal < data->min_num_chal) {
		wpa_printf(MSG_INFO, "EAP-SIM: Insufficient number of "
			   "challenges (%lu)", (unsigned long) attr->num_chal);
		return eap_sim_client_error(data, id,
					    EAP_SIM_INSUFFICIENT_NUM_OF_CHAL);
	}
	if (attr->num_chal > 3) {
		wpa_printf(MSG_INFO, "EAP-SIM: Too many challenges "
			   "(%lu)", (unsigned long) attr->num_chal);
		return eap_sim_client_error(data, id,
					    EAP_SIM_UNABLE_TO_PROCESS_PACKET);
	}

	/* Verify that RANDs are different */
	if (os_memcmp(attr->rand, attr->rand + GSM_RAND_LEN,
		   GSM_RAND_LEN) == 0 ||
	    (attr->num_chal > 2 &&
	     (os_memcmp(attr->rand, attr->rand + 2 * GSM_RAND_LEN,
			GSM_RAND_LEN) == 0 ||
	      os_memcmp(attr->rand + GSM_RAND_LEN,
			attr->rand + 2 * GSM_RAND_LEN,
			GSM_RAND_LEN) == 0))) {
		wpa_printf(MSG_INFO, "EAP-SIM: Same RAND used multiple times");
		return eap_sim_client_error(data, id,
					    EAP_SIM_RAND_NOT_FRESH);
	}

	os_memcpy(data->rand, attr->rand, attr->num_chal * GSM_RAND_LEN);
	data->num_chal = attr->num_chal;
		
	if (eap_sim_gsm_auth(sm, data)) {
		wpa_printf(MSG_WARNING, "EAP-SIM: GSM authentication failed");
		return eap_sim_client_error(data, id,
					    EAP_SIM_UNABLE_TO_PROCESS_PACKET);
	}
	if (data->last_eap_identity) {
		identity = data->last_eap_identity;
		identity_len = data->last_eap_identity_len;
	} else if (data->pseudonym) {
		identity = data->pseudonym;
		identity_len = data->pseudonym_len;
	} else
		identity = eap_get_config_identity(sm, &identity_len);
	wpa_hexdump_ascii(MSG_DEBUG, "EAP-SIM: Selected identity for MK "
			  "derivation", identity, identity_len);
	eap_sim_derive_mk(identity, identity_len, data->nonce_mt,
			  data->selected_version, data->ver_list,
			  data->ver_list_len, data->num_chal,
			  (const u8 *) data->kc, data->mk);
	eap_sim_derive_keys(data->mk, data->k_encr, data->k_aut, data->msk,
			    data->emsk);
	if (eap_sim_verify_mac(data->k_aut, reqData, attr->mac, data->nonce_mt,
			       EAP_SIM_NONCE_MT_LEN)) {
		wpa_printf(MSG_WARNING, "EAP-SIM: Challenge message "
			   "used invalid AT_MAC");
		return eap_sim_client_error(data, id,
					    EAP_SIM_UNABLE_TO_PROCESS_PACKET);
	}

	/* Old reauthentication identity must not be used anymore. In
	 * other words, if no new reauth identity is received, full
	 * authentication will be used on next reauthentication (using
	 * pseudonym identity or permanent identity). */
	eap_sim_clear_identities(data, CLEAR_REAUTH_ID | CLEAR_EAP_ID);

	if (attr->encr_data) {
		u8 *decrypted;
		decrypted = eap_sim_parse_encr(data->k_encr, attr->encr_data,
					       attr->encr_data_len, attr->iv,
					       &eattr, 0);
		if (decrypted == NULL) {
			return eap_sim_client_error(
				data, id, EAP_SIM_UNABLE_TO_PROCESS_PACKET);
		}
		eap_sim_learn_ids(sm, data, &eattr);
		os_free(decrypted);
	}

	if (data->result_ind && attr->result_ind)
		data->use_result_ind = 1;

	if (data->state != FAILURE && data->state != RESULT_FAILURE) {
		eap_sim_state(data, data->use_result_ind ?
			      RESULT_SUCCESS : SUCCESS);
	}

	data->num_id_req = 0;
	data->num_notification = 0;
	/* RFC 4186 specifies that counter is initialized to one after
	 * fullauth, but initializing it to zero makes it easier to implement
	 * reauth verification. */
	data->counter = 0;
	return eap_sim_response_challenge(data, id);
}