eapol/eapol_framework/eapol_common/type/gsmsim/core/eap_type_gsmsim_server.cpp
changeset 0 c8830336c852
child 2 1c7bc153c08e
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/eapol/eapol_framework/eapol_common/type/gsmsim/core/eap_type_gsmsim_server.cpp	Thu Dec 17 08:47:43 2009 +0200
@@ -0,0 +1,4746 @@
+/*
+* Copyright (c) 2001-2006 Nokia Corporation and/or its subsidiary(-ies).
+* All rights reserved.
+* This component and the accompanying materials are made available
+* under the terms of the License "Eclipse Public License v1.0"
+* which accompanies this distribution, and is available
+* at the URL "http://www.eclipse.org/legal/epl-v10.html".
+*
+* Initial Contributors:
+* Nokia Corporation - initial contribution.
+*
+* Contributors:
+*
+* Description:  EAP and WLAN authentication protocols.
+*
+*/
+
+
+// This is enumeration of EAPOL source code.
+#if defined(USE_EAP_MINIMUM_RELEASE_TRACES)
+	#undef EAP_FILE_NUMBER_ENUM
+	#define EAP_FILE_NUMBER_ENUM 82 
+	#undef EAP_FILE_NUMBER_DATE 
+	#define EAP_FILE_NUMBER_DATE 1127594498 
+#endif //#if defined(USE_EAP_MINIMUM_RELEASE_TRACES)
+
+
+#if defined(USE_EAP_TYPE_SERVER_GSMSIM)
+
+#include "eap_am_memory.h"
+#include "eap_tools.h"
+#include "eap_type_gsmsim.h"
+#include "eap_type_gsmsim_header.h"
+#include "eap_type_gsmsim_payloads.h"
+#include "eap_type_gsmsim_mac_attributes.h"
+#include "abs_eap_am_type_gsmsim.h"
+#include "eap_crypto_api.h"
+#include "eap_state_notification.h"
+#include "eap_automatic_variable.h"
+#include "eap_am_type_gsmsim.h"
+
+
+//--------------------------------------------------
+
+/** @file */
+
+//--------------------------------------------------
+
+//
+EAP_FUNC_EXPORT eap_status_e eap_type_gsmsim_c::add_n_rand_payload(
+	gsmsim_header_c * const gsmsim,
+	const u32_t gsmsim_buffer_length,
+	const u32_t eap_header_size,
+	u32_t * const gsmsim_data_offset,
+	u32_t * const gsmsim_data_free,
+	u32_t * const packet_buffer_free,
+	u32_t * const packet_buffer_offset,
+	eap_type_sim_triplet_array_c * const triplets)
+{
+	EAP_TRACE_BEGIN(m_am_tools, TRACE_FLAGS_DEFAULT);
+
+	eap_status_e status = eap_status_process_general_error;
+	gsmsim_payload_AT_header_c gp_n_rands(
+		m_am_tools,
+		gsmsim->get_data_offset(*gsmsim_data_offset, *gsmsim_data_free),
+		*gsmsim_data_free);
+
+	if (gp_n_rands.get_is_valid() == false)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+	}
+
+	u32_t rand_data_length = triplets->get_triplet_count() * SIM_RAND_LENGTH;
+
+
+	gp_n_rands.reset_header(static_cast<u16_t>(rand_data_length));
+	gp_n_rands.set_current_payload(gsmsim_payload_AT_RAND);
+
+	u8_t *n_rands = gp_n_rands.get_data(rand_data_length);
+	if (n_rands == 0)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_process_general_error);
+	}
+
+	for (u32_t ind = 0u; ind < triplets->get_triplet_count(); ind++)
+	{
+		eap_type_saesim_triplet_c *triplet = triplets->get_triplet(m_am_tools, ind);
+
+		u8_t * const source = triplet->get_rand()->get_data();
+		if (source == 0)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, eap_status_allocation_error);
+		}
+
+		m_am_tools->memmove(
+			n_rands+(ind*SIM_RAND_LENGTH),
+			source,
+			triplet->get_rand()->get_data_length());
+	}
+
+	status = eap_status_ok;
+
+	update_payload_indexes(
+		gsmsim_buffer_length,
+		eap_header_size,
+		gp_n_rands.get_header_length()+gp_n_rands.get_data_length(),
+		gsmsim_data_offset,
+		gsmsim_data_free,
+		packet_buffer_offset,
+		packet_buffer_free);
+
+	EAP_GSMSIM_TRACE_PAYLOAD("Payload added", &gp_n_rands);
+
+	EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+	return EAP_STATUS_RETURN(m_am_tools, status);
+}
+
+
+//--------------------------------------------------
+
+//
+EAP_FUNC_EXPORT eap_status_e eap_type_gsmsim_c::send_reauthentication_request_message(
+	const eap_variable_data_c * const username,
+	const bool pseudonym_decode_failed,
+	const u8_t eap_identifier)
+{
+	EAP_TRACE_BEGIN(m_am_tools, TRACE_FLAGS_DEFAULT);
+
+	EAP_UNREFERENCED_PARAMETER(pseudonym_decode_failed);
+
+	EAP_TRACE_DEBUG(
+		m_am_tools, 
+		TRACE_FLAGS_DEFAULT, 
+		(EAPL("    send: GSMSIM-subtype %10s, %s, state %2d=%s\n"),
+		 EAPL("gsmsim_subtype_Re_authentication"),
+		 EAPL("server"),
+		 m_state,
+		 get_state_string()
+		 ));
+
+	EAP_TRACE_DEBUG(
+		m_am_tools,
+		TRACE_FLAGS_DEFAULT,
+		(EAPL("eap_type_gsmsim_c::send_reauthentication_request_message(): %s, m_identity_type %d=%s, requested identity payload is %d=%s.\n"),
+		 (m_is_client == true ? "client": "server"),
+		 m_identity_type,
+		 get_identity_string(m_identity_type),
+		 m_start_response_includes_identity,
+		 gsmsim_payload_AT_header_c::get_payload_AT_string(m_start_response_includes_identity)));
+
+	eap_status_e status = eap_status_process_general_error;
+
+	eap_buf_chain_wr_c request_packet(
+		eap_write_buffer, 
+		m_am_tools, 
+		EAP_MAX_LOCAL_PACKET_BUFFER_LENGTH);
+
+	if (request_packet.get_is_valid() == false)
+	{
+		EAP_TRACE_ERROR(m_am_tools, TRACE_FLAGS_DEFAULT, (EAPL("packet buffer corrupted.\n")));
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_allocation_error);
+	}
+
+#if defined(USE_EAP_TYPE_GSMSIM_OWN_RE_TRANSMISSION)
+	if (m_is_client == true
+		&& m_client_responds_retransmitted_packets == true)
+	{
+		// We do not wan't lower layers do re-transmissions behalf of us.
+		// This means GSMSIM does process every re-transmitted EAP-Request.
+		request_packet.set_do_packet_retransmission(false);
+	}
+#endif //#if defined(USE_EAP_TYPE_GSMSIM_OWN_RE_TRANSMISSION)
+
+	EAP_ASSERT_ALWAYS(EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH >= (m_gsmsim_header_offset+m_trailer_length));
+	u32_t packet_buffer_free = EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH-m_trailer_length;
+	u32_t packet_buffer_offset = 0u;
+
+	if (m_gsmsim_header_offset+m_MTU < packet_buffer_free)
+	{
+		packet_buffer_free = m_gsmsim_header_offset+m_MTU;
+	}
+
+	gsmsim_header_c gsmsim_response(
+		m_am_tools,
+		request_packet.get_data_offset(
+			m_gsmsim_header_offset,
+			(packet_buffer_free-m_gsmsim_header_offset)),
+		(packet_buffer_free-m_gsmsim_header_offset));
+
+	if (gsmsim_response.get_is_valid() == false)
+	{
+		EAP_TRACE_ERROR(
+			m_am_tools,
+			TRACE_FLAGS_DEFAULT,
+			(EAPL("send_reauthentication_request_message: packet buffer corrupted.\n")));
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_process_general_error);
+	}
+
+	gsmsim_response.reset_header(
+		packet_buffer_free-m_gsmsim_header_offset,
+		m_use_eap_expanded_type);
+	gsmsim_response.set_length(
+		static_cast<u16_t>(packet_buffer_free-m_gsmsim_header_offset),
+		m_use_eap_expanded_type);
+	gsmsim_response.set_code(eap_code_request);
+	gsmsim_response.set_identifier(eap_identifier);
+	gsmsim_response.set_type(
+		eap_type_gsmsim,
+		m_use_eap_expanded_type);
+	gsmsim_response.set_subtype(gsmsim_subtype_Re_authentication);
+
+	update_buffer_indexes(
+		EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+		m_gsmsim_header_offset+gsmsim_response.get_header_length(),
+		&packet_buffer_offset,
+		&packet_buffer_free);
+
+	// - - - - - - - - - - - - - - - - - - - - - - - -
+
+	EAP_TRACE_DEBUG(
+		m_am_tools, 
+		TRACE_FLAGS_DEFAULT, 
+		(EAPL("eap_type_gsmsim_c::send_reauthentication_request_message(0x%08x).\n"),
+		this));
+
+	// - - - - - - - - - - - - - - - - - - - - - - - -
+
+	u32_t gsmsim_data_free = packet_buffer_free;
+	u32_t gsmsim_data_offset = 0u;
+
+	eap_variable_data_c orig_XKEY(m_am_tools);
+	eap_variable_data_c orig_K_aut(m_am_tools);
+	eap_variable_data_c orig_K_encr(m_am_tools);
+	u32_t reauth_counter = 0u;
+	eap_variable_data_c reauth_nonce_s(m_am_tools);
+
+
+	// In order to use re-authentication, the client and the server need to
+	// store the following values: original XKEY, K_aut, K_encr, latest
+	// counter value and the next re-authentication identity.
+	status = m_am_type_gsmsim->query_reauth_parameters(
+		&orig_XKEY,
+		&orig_K_aut,
+		&orig_K_encr,
+		&reauth_counter);
+	if (status != eap_status_ok)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+
+	EAP_TRACE_DEBUG(
+		m_am_tools,
+		TRACE_FLAGS_DEFAULT,
+		(EAPL("eap_type_gsmsim_c::send_reauthentication_request_message(): %s, m_saved_reauth_counter %d.\n"),
+		 (m_is_client == true ? "client": "server"),
+		 reauth_counter));
+
+	status = generate_nonce(EAP_TYPE_GSMSIM_NONCE_MT_SIZE, &reauth_nonce_s);
+	if (status != eap_status_ok)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+
+	status = m_nonce_s.set_copy_of_buffer(&reauth_nonce_s);
+	if (status != eap_status_ok)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+
+	eap_variable_data_c master_session_key(m_am_tools);
+
+	status = generate_reauth_shared_secred_keys(
+		EAP_TYPE_GSMSIM_KEYMAT_SIZE,
+		&orig_XKEY,
+		reauth_counter,
+		username,
+		&reauth_nonce_s,
+		&master_session_key);
+	if (status != eap_status_ok)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+
+	// -   -   -   -   -   -   -   -   -   -   -   -
+
+	m_use_result_indication = m_allow_use_result_indication;
+
+	if (m_use_result_indication == true)
+	{
+		// We support use of protected success indications.
+		status = add_simple_payload(
+			&gsmsim_response,
+			EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+			gsmsim_response.get_header_length(),
+			&gsmsim_data_offset,
+			&gsmsim_data_free,
+			&packet_buffer_free,
+			&packet_buffer_offset,
+			gsmsim_payload_AT_RESULT_IND);
+		if (status != eap_status_ok)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+	}
+
+	// -   -   -   -   -   -   -   -   -   -   -   -
+
+	crypto_aes_c aes(m_am_tools);
+
+	if (aes.get_is_valid() == false)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_allocation_error);
+	}
+
+	status = m_am_type_gsmsim->generate_encryption_IV(
+		m_IV.get_payload_buffer(),
+		aes.get_block_size());
+	if (status != eap_status_ok)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+
+	// -   -   -   -   -   -   -   -   -   -   -   -
+
+	status = add_variable_payload(
+		&gsmsim_response,
+		EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+		gsmsim_response.get_header_length(),
+		&gsmsim_data_offset,
+		&gsmsim_data_free,
+		&packet_buffer_free,
+		&packet_buffer_offset,
+		m_IV.get_payload_buffer(),
+		gsmsim_payload_AT_IV);
+	if (status != eap_status_ok)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+
+
+	u8_t *MAC_data = 0;
+	u32_t MAC_data_length = 0u;
+	eap_type_gsmsim_MAC_attributes_c MAC_attributes;
+
+	// Encrypted data.
+	{
+		gsmsim_payload_AT_header_c gp_encrypted_data(
+			m_am_tools,
+			gsmsim_response.get_data_offset(
+				gsmsim_data_offset, 
+				gsmsim_data_free),
+			gsmsim_data_free);
+		if (gsmsim_response.get_is_valid() == false)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_parameter);
+		}
+
+		// Initialize the length of encrypted data to maximum length.
+		// Later this will be set to correct length.
+		gp_encrypted_data.reset_header(gsmsim_payload_AT_header_c::get_max_payload_data_length());
+		gp_encrypted_data.set_current_payload(gsmsim_payload_AT_ENCR_DATA);
+
+		update_payload_indexes(
+			EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+			gsmsim_response.get_header_length(),
+			gp_encrypted_data.get_header_length(),
+			&gsmsim_data_offset,
+			&gsmsim_data_free,
+			&packet_buffer_offset,
+			&packet_buffer_free);
+
+		u32_t encrypted_data_offset_begin = packet_buffer_offset;
+
+		// -   -   -   -   -   -   -   -   -   -   -   -
+
+		status = add_counter_payload(
+			&gsmsim_response,
+			EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+			gsmsim_response.get_header_length(),
+			&gsmsim_data_offset,
+			&gsmsim_data_free,
+			&packet_buffer_free,
+			&packet_buffer_offset,
+			static_cast<u16_t>(reauth_counter));
+		if (status != eap_status_ok)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+
+		// -   -   -   -   -   -   -   -   -   -   -   -
+
+		status = add_variable_payload(
+			&gsmsim_response,
+			EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+			gsmsim_response.get_header_length(),
+			&gsmsim_data_offset,
+			&gsmsim_data_free,
+			&packet_buffer_free,
+			&packet_buffer_offset,
+			&reauth_nonce_s,
+			gsmsim_payload_AT_NONCE_S);
+		if (status != eap_status_ok)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+
+		// -   -   -   -   -   -   -   -   -   -   -   -
+
+		status = m_am_type_gsmsim->generate_reauthentication_id(
+			&m_send_network_id,
+			&m_IMSI,
+			&m_reauthentication_identity,
+			EAP_TYPE_GSMSIM_MAX_NAI_LENGTH);
+		if (status == eap_status_ok)
+		{
+			status = add_pseudonym_or_imsi_payload(
+				&gsmsim_response,
+				EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+				gsmsim_response.get_header_length(),
+				&gsmsim_data_offset,
+				&gsmsim_data_free,
+				&packet_buffer_free,
+				&packet_buffer_offset,
+				&m_reauthentication_identity,
+				gsmsim_payload_AT_NEXT_REAUTH_ID);
+			if (status != eap_status_ok)
+			{
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, status);
+			}
+		}
+
+		// -   -   -   -   -   -   -   -   -   -   -   -
+
+		status = add_padding_payload(
+			&gsmsim_response,
+			EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+			gsmsim_response.get_header_length(),
+			&gsmsim_data_offset,
+			&gsmsim_data_free,
+			&packet_buffer_free,
+			&packet_buffer_offset,
+			(packet_buffer_offset - encrypted_data_offset_begin) // Length of the plain text.
+			);
+		if (status != eap_status_ok)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+
+		gp_encrypted_data.set_data_length(
+			static_cast<u16_t>(packet_buffer_offset - encrypted_data_offset_begin));
+
+		// -   -   -   -   -   -   -   -   -   -   -   -
+
+		status = encrypt_DATA_payload(
+			gp_encrypted_data.get_data(gp_encrypted_data.get_data_length()),
+			gp_encrypted_data.get_data_length(),
+			m_IV.get_payload_buffer(),
+			&orig_K_encr);
+		if (status != eap_status_ok)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+
+		EAP_GSMSIM_TRACE_PAYLOAD("Payload added", &gp_encrypted_data);
+	}
+
+	// -   -   -   -   -   -   -   -   -   -   -   -
+
+	status = add_mac_payload(
+		&gsmsim_response,
+		EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+		gsmsim_response.get_header_length(),
+		&gsmsim_data_offset,
+		&gsmsim_data_free,
+		&packet_buffer_free,
+		&packet_buffer_offset,
+		&MAC_data,
+		&MAC_data_length);
+	if (status != eap_status_ok)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+
+	// -   -   -   -   -   -   -   -   -   -   -   -
+
+	gsmsim_response.set_data_length(
+		gsmsim_data_offset,
+		m_use_eap_expanded_type);
+
+	request_packet.set_data_length(packet_buffer_offset);
+
+	EAP_ASSERT_ALWAYS(
+		m_gsmsim_header_offset+gsmsim_response.get_header_length()+gsmsim_response.get_data_length()
+		== packet_buffer_offset);
+
+	// -   -   -   -   -   -   -   -   -   -   -   -
+
+	MAC_attributes.init(
+		MAC_data,
+		MAC_data_length,
+		gsmsim_response.get_header_buffer(gsmsim_response.get_length()),
+		gsmsim_response.get_length());
+
+	status = create_message_authentication_code(
+		&MAC_attributes,
+		gsmsim_response.get_subtype(),
+		gsmsim_response.get_code(),
+		&orig_K_aut);
+	if (status != eap_status_ok)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+
+	// - - - - - - - - - - - - - - - - - - - - - - - -
+
+	gsmsim_response.set_data_length(
+		gsmsim_data_offset,
+		m_use_eap_expanded_type);
+
+	request_packet.set_data_length(packet_buffer_offset);
+
+	EAP_ASSERT_ALWAYS(
+		m_gsmsim_header_offset+gsmsim_response.get_header_length()+gsmsim_response.get_data_length()
+		== packet_buffer_offset);
+
+	// - - - - - - - - - - - - - - - - - - - - - - - -
+
+	EAP_TRACE_DEBUG(
+		m_am_tools, 
+		TRACE_FLAGS_DEFAULT, 
+		(EAPL("eap_type_gsmsim_c::send_reauthentication_request_message()\n")));
+
+	status = packet_send(
+		&m_send_network_id,
+		&request_packet,
+		m_gsmsim_header_offset,
+		gsmsim_response.get_header_length()+gsmsim_response.get_data_length(),
+		EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH
+		);
+
+	if (status == eap_status_ok)
+	{
+		status = m_master_session_key.set_copy_of_buffer(&master_session_key);
+		if (status != eap_status_ok)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+		set_state(eap_type_gsmsim_state_waiting_for_reauth_response);
+	}
+
+	// - - - - - - - - - - - - - - - - - - - - - - - -
+
+	EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+	return EAP_STATUS_RETURN(m_am_tools, status);
+}
+
+//--------------------------------------------------
+
+//
+EAP_FUNC_EXPORT eap_status_e eap_type_gsmsim_c::send_start_request_message(
+	const bool pseudonym_decode_failed,
+	const u8_t eap_identifier)
+{
+	EAP_TRACE_BEGIN(m_am_tools, TRACE_FLAGS_DEFAULT);
+
+	EAP_TRACE_DEBUG(
+		m_am_tools, 
+		TRACE_FLAGS_DEFAULT, 
+		(EAPL("    send: %s, GSMSIM-subtype %10s, %s, state %2d=%s\n"),
+		 EAPL("initiator"),
+		 EAPL("gsmsim_subtype_Start"),
+		 EAPL("server"),
+		 m_state,
+		 get_state_string()
+		 ));
+
+	EAP_TRACE_DEBUG(
+		m_am_tools, 
+		TRACE_FLAGS_DEFAULT, 
+		(EAPL("eap_type_gsmsim_c::send_start_request_message(): ")
+		 EAPL("m_identity_type %d=%s, requested identity payload is %d=%s, state %d=%s, pseudonym decode %d.\n"),
+		 m_identity_type,
+		 get_identity_string(m_identity_type),
+		 m_start_response_includes_identity,
+		 gsmsim_payload_AT_header_c::get_payload_AT_string(m_start_response_includes_identity),
+		 m_state,
+		 get_state_string(),
+		 pseudonym_decode_failed));
+
+	eap_status_e status = eap_status_process_general_error;
+
+	eap_buf_chain_wr_c request_packet(
+		eap_write_buffer, 
+		m_am_tools, 
+		EAP_MAX_LOCAL_PACKET_BUFFER_LENGTH);
+
+	if (request_packet.get_is_valid() == false)
+	{
+		EAP_TRACE_ERROR(m_am_tools, TRACE_FLAGS_DEFAULT, (EAPL("packet buffer corrupted.\n")));
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_allocation_error);
+	}
+
+#if defined(USE_EAP_TYPE_GSMSIM_OWN_RE_TRANSMISSION)
+	if (m_is_client == true
+		&& m_client_responds_retransmitted_packets == true)
+	{
+		// We do not wan't lower layers do re-transmissions behalf of us.
+		// This means GSMSIM does process every re-transmitted EAP-Request.
+		request_packet.set_do_packet_retransmission(false);
+	}
+#endif //#if defined(USE_EAP_TYPE_GSMSIM_OWN_RE_TRANSMISSION)
+
+	EAP_ASSERT_ALWAYS(EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH >= (m_gsmsim_header_offset+m_trailer_length));
+	u32_t packet_buffer_free = EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH-m_trailer_length;
+	u32_t packet_buffer_offset = 0u;
+
+	if (m_gsmsim_header_offset+m_MTU < packet_buffer_free)
+	{
+		packet_buffer_free = m_gsmsim_header_offset+m_MTU;
+	}
+
+	gsmsim_header_c gsmsim_response(
+		m_am_tools,
+		request_packet.get_data_offset(
+			m_gsmsim_header_offset,
+			(packet_buffer_free-m_gsmsim_header_offset)),
+		(packet_buffer_free-m_gsmsim_header_offset));
+
+	if (gsmsim_response.get_is_valid() == false)
+	{
+		EAP_TRACE_ERROR(
+			m_am_tools, 
+			TRACE_FLAGS_DEFAULT, 
+			(EAPL("send_start_request_message: packet buffer corrupted.\n")));
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+	}
+
+	gsmsim_response.reset_header(
+		packet_buffer_free-m_gsmsim_header_offset,
+		m_use_eap_expanded_type);
+	gsmsim_response.set_length(
+		static_cast<u16_t>(packet_buffer_free-m_gsmsim_header_offset),
+		m_use_eap_expanded_type);
+	gsmsim_response.set_code(eap_code_request);
+	gsmsim_response.set_identifier(eap_identifier);
+	gsmsim_response.set_type(
+		eap_type_gsmsim,
+		m_use_eap_expanded_type);
+	gsmsim_response.set_subtype(gsmsim_subtype_Start);
+
+	update_buffer_indexes(
+		EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+		m_gsmsim_header_offset+gsmsim_response.get_header_length(),
+		&packet_buffer_offset,
+		&packet_buffer_free);
+
+	// - - - - - - - - - - - - - - - - - - - - - - - -
+
+	EAP_TRACE_DEBUG(
+		m_am_tools, 
+		TRACE_FLAGS_DEFAULT, 
+		(EAPL("eap_type_gsmsim_c::send_start_request_message(0x%08x).\n"),
+		 this));
+
+	// - - - - - - - - - - - - - - - - - - - - - - - -
+
+	u32_t gsmsim_data_free = packet_buffer_free;
+	u32_t gsmsim_data_offset = 0u;
+
+	if (pseudonym_decode_failed == true)
+	{
+		gsmsim_payload_AT_type_e next_identity_request = gsmsim_payload_NONE;
+		eap_type_gsmsim_state_variable_e next_state = eap_type_gsmsim_state_failure;
+
+		if (m_identity.get_is_valid_data() == true)
+		{
+			if (m_start_response_includes_identity == gsmsim_payload_AT_FULLAUTH_ID_REQ)
+			{
+				next_identity_request = gsmsim_payload_AT_FULLAUTH_ID_REQ;
+				next_state = eap_type_gsmsim_state_waiting_for_start_response_with_at_full_auth_identity;
+			}
+			else if (m_start_response_includes_identity == gsmsim_payload_AT_PERMANENT_ID_REQ)
+			{
+				next_identity_request = gsmsim_payload_AT_PERMANENT_ID_REQ;
+				next_state = eap_type_gsmsim_state_waiting_for_start_response_with_at_permanent_identity;
+			}
+			else if (m_start_response_includes_identity == gsmsim_payload_AT_ANY_ID_REQ)
+			{
+				next_identity_request = gsmsim_payload_AT_ANY_ID_REQ;
+				next_state = eap_type_gsmsim_state_waiting_for_start_response_with_at_any_identity;
+			}
+			else
+			{
+				// We drop this message because no real identity is received from client.
+				EAP_TRACE_ERROR(m_am_tools, TRACE_FLAGS_GSMSIM_ERROR, (EAPL("ERROR: send_start_request_message: no real identity received.\n")));
+				return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_eap_identity);
+			}
+		}
+		else
+		{
+			next_identity_request = gsmsim_payload_AT_ANY_ID_REQ;
+			next_state = eap_type_gsmsim_state_waiting_for_start_response_with_at_any_identity;
+		}
+
+		status = add_variable_payload(
+			&gsmsim_response,
+			EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+			gsmsim_response.get_header_length(),
+			&gsmsim_data_offset,
+			&gsmsim_data_free,
+			&packet_buffer_free,
+			&packet_buffer_offset,
+			0,
+			next_identity_request);
+		if (status != eap_status_ok)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+
+		set_state(next_state);
+	}
+	else
+	{
+		set_state(eap_type_gsmsim_state_waiting_for_start_response);
+	}
+
+	// - - - - - - - - - - - - - - - - - - - - - - - -
+
+
+	eap_gsmsim_version version_list = GSMSIM_VERSION_1;
+
+	status = add_version_list(
+		&gsmsim_response,
+		EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+		gsmsim_response.get_header_length(),
+		&gsmsim_data_offset,
+		&gsmsim_data_free,
+		&packet_buffer_free,
+		&packet_buffer_offset,
+		&version_list,
+		sizeof(version_list)/sizeof(eap_gsmsim_version),
+		gsmsim_payload_AT_VERSION_LIST);
+	if (status != eap_status_ok)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+
+
+	// - - - - - - - - - - - - - - - - - - - - - - - -
+
+	gsmsim_response.set_data_length(
+		gsmsim_data_offset,
+		m_use_eap_expanded_type);
+
+	request_packet.set_data_length(packet_buffer_offset);
+
+	EAP_ASSERT_ALWAYS(
+		m_gsmsim_header_offset+gsmsim_response.get_header_length()+gsmsim_response.get_data_length()
+		== packet_buffer_offset);
+
+	EAP_TRACE_DEBUG(
+		m_am_tools, 
+		TRACE_FLAGS_DEFAULT, 
+		(EAPL("eap_type_gsmsim_c::send_start_request_message()\n")));
+
+	status = packet_send(
+		&m_send_network_id,
+		&request_packet,
+		m_gsmsim_header_offset,
+		gsmsim_response.get_header_length()+gsmsim_response.get_data_length(),
+		EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH
+		);
+
+	if (status == eap_status_ok)
+	{
+	}
+
+	// - - - - - - - - - - - - - - - - - - - - - - - -
+
+	EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+	return EAP_STATUS_RETURN(m_am_tools, status);
+}
+
+//--------------------------------------------------
+
+//
+EAP_FUNC_EXPORT eap_status_e eap_type_gsmsim_c::send_challenge_request_message(
+		const u8_t eap_identifier)
+{
+	EAP_TRACE_BEGIN(m_am_tools, TRACE_FLAGS_DEFAULT);
+
+	EAP_TRACE_DEBUG(
+		m_am_tools, 
+		TRACE_FLAGS_DEFAULT, 
+		(EAPL("    send: GSMSIM-type %10s, %s, state %2d=%s\n"),
+		 EAPL("gsmsim_subtype_Challenge"),
+		 (m_is_client) ? EAPL("client") : EAPL("server"),
+		 m_state,
+		 get_state_string()
+		 ));
+
+	eap_buf_chain_wr_c gsmsim_initial_reply(
+		eap_write_buffer, 
+		m_am_tools, 
+		EAP_MAX_LOCAL_PACKET_BUFFER_LENGTH);
+
+	if (gsmsim_initial_reply.get_is_valid() == false)
+	{
+		EAP_TRACE_ERROR(
+			m_am_tools, 
+			TRACE_FLAGS_DEFAULT, 
+			(EAPL("packet buffer corrupted.\n")));
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_allocation_error);
+	}
+
+#if defined(USE_EAP_TYPE_GSMSIM_OWN_RE_TRANSMISSION)
+	if (m_is_client == true
+		&& m_client_responds_retransmitted_packets == true)
+	{
+		// We do not wan't lower layers do re-transmissions behalf of us.
+		// This means GSMSIM does process every re-transmitted EAP-Request.
+		gsmsim_initial_reply.set_do_packet_retransmission(false);
+	}
+#endif //#if defined(USE_EAP_TYPE_GSMSIM_OWN_RE_TRANSMISSION)
+
+	EAP_ASSERT_ALWAYS(EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH >= (m_gsmsim_header_offset+m_trailer_length));
+	u32_t packet_buffer_free = EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH-m_trailer_length;
+	u32_t packet_buffer_offset = 0u;
+
+	if (m_gsmsim_header_offset+m_MTU < packet_buffer_free)
+	{
+		packet_buffer_free = m_gsmsim_header_offset+m_MTU;
+	}
+
+	gsmsim_header_c gsmsim_response(
+		m_am_tools,
+		gsmsim_initial_reply.get_data_offset(
+			m_gsmsim_header_offset,
+			(packet_buffer_free-m_gsmsim_header_offset)),
+		(packet_buffer_free-m_gsmsim_header_offset));
+
+	if (gsmsim_response.get_is_valid() == false)
+	{
+		EAP_TRACE_ERROR(
+			m_am_tools, 
+			TRACE_FLAGS_DEFAULT, 
+			(EAPL("packet_send: packet buffer corrupted.\n")));
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+	}
+
+	gsmsim_response.reset_header(
+		packet_buffer_free-m_gsmsim_header_offset,
+		m_use_eap_expanded_type);
+	gsmsim_response.set_length(
+		static_cast<u16_t>(packet_buffer_free-m_gsmsim_header_offset),
+		m_use_eap_expanded_type);
+	gsmsim_response.set_code(eap_code_request);
+	gsmsim_response.set_identifier(eap_identifier);
+	gsmsim_response.set_type(
+		eap_type_gsmsim,
+		m_use_eap_expanded_type);
+
+	gsmsim_response.set_subtype(gsmsim_subtype_Challenge);
+
+	EAP_TRACE_DEBUG(
+		m_am_tools, 
+		TRACE_FLAGS_DEFAULT, 
+		(EAPL("eap_type_gsmsim_c::send_challenge_request_message(0x%08x).\n"),
+		this));
+
+	update_buffer_indexes(
+		EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+		m_gsmsim_header_offset+gsmsim_response.get_header_length(),
+		&packet_buffer_offset,
+		&packet_buffer_free);
+
+	// - - - - - - - - - - - - - - - - - - - - - - - -
+
+	u32_t gsmsim_data_free = packet_buffer_free;
+	u32_t gsmsim_data_offset = 0u;
+	eap_status_e status = eap_status_process_general_error;
+
+	// - - - - - - - - - - - - - - - - - - - - - - - -
+
+	eap_variable_data_c n_rand(m_am_tools);
+	eap_variable_data_c n_kc(m_am_tools);
+
+	u32_t count = m_triplets->get_triplet_count();
+
+	if (count == 0u)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_process_general_error);
+	}
+
+	status = n_rand.init(SIM_RAND_LENGTH*count);
+	if (status != eap_status_ok)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+	n_rand.set_is_valid();
+	n_rand.set_data_length(0u);
+
+	status = n_kc.init(SIM_KC_LENGTH*count);
+	if (status != eap_status_ok)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+	n_kc.set_is_valid();
+	n_kc.set_data_length(0u);
+
+	status = m_n_sres.init(SIM_KC_LENGTH*count);
+	if (status != eap_status_ok)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+	m_n_sres.set_is_valid();
+	m_n_sres.set_data_length(0u);
+
+	u32_t ind;
+	for (ind = 0u; ind < count; ind++)
+	{
+		eap_type_saesim_triplet_c *tripl = m_triplets->get_triplet(m_am_tools, ind);
+		if (tripl == 0
+			|| tripl->get_rand()->get_data_length() == 0u
+			|| tripl->get_kc()->get_data_length() == 0u
+			|| tripl->get_sres()->get_data_length() == 0u)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, eap_status_process_general_error);
+		}
+
+		n_rand.add_data(
+			tripl->get_rand()->get_data(),
+			tripl->get_rand()->get_data_length());
+
+		n_kc.add_data(
+			tripl->get_kc()->get_data(),
+			tripl->get_kc()->get_data_length());
+
+		m_n_sres.add_data(
+			tripl->get_sres()->get_data(),
+			tripl->get_sres()->get_data_length());
+	} // for()
+
+
+	if (n_rand.get_is_valid_data() == false)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_process_general_error);
+	}
+
+	if (n_kc.get_is_valid_data() == false)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_process_general_error);
+	}
+
+	if (m_n_sres.get_is_valid_data() == false)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_process_general_error);
+	}
+
+	if (m_identity.get_is_valid_data() == false)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_process_general_error);
+	}
+
+	if (m_IMSI.get_is_valid_data() == false)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_process_general_error);
+	}
+
+	if (m_nonce_mt.get_is_valid_data() == false)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_process_general_error);
+	}
+
+	EAP_TRACE_DATA_DEBUG(m_am_tools, TRACE_FLAGS_DEFAULT|TRACE_TEST_VECTORS, (EAPL("n*RAND"),
+		n_rand.get_data(),
+		n_rand.get_data_length()));
+	EAP_TRACE_DATA_DEBUG(m_am_tools, TRACE_FLAGS_DEFAULT, (EAPL("n*KC"),
+		n_kc.get_data(),
+		n_kc.get_data_length()));
+	EAP_TRACE_DATA_DEBUG(m_am_tools, TRACE_FLAGS_DEFAULT, (EAPL("n*SRES"),
+		m_n_sres.get_data(),
+		m_n_sres.get_data_length()));
+	EAP_TRACE_DATA_DEBUG(m_am_tools, TRACE_FLAGS_DEFAULT, (EAPL("identity"),
+		m_identity.get_data(),
+		m_identity.get_data_length()));
+	EAP_TRACE_DATA_DEBUG(m_am_tools, TRACE_FLAGS_DEFAULT, (EAPL("IMSI"),
+		m_IMSI.get_data(),
+		m_IMSI.get_data_length()));
+	EAP_TRACE_DATA_DEBUG(m_am_tools, TRACE_FLAGS_DEFAULT, (EAPL("NONCE MT"),
+		m_nonce_mt.get_data(),
+		m_nonce_mt.get_data_length()));
+
+
+	eap_variable_data_c XKEY(m_am_tools);
+	eap_variable_data_c K_encr(m_am_tools);
+	eap_variable_data_c K_aut(m_am_tools);
+	eap_variable_data_c master_session_key(m_am_tools);
+
+	status = generate_shared_secred_keys(
+		EAP_TYPE_GSMSIM_KEYMAT_SIZE,
+		&n_kc,
+		&m_n_sres,
+		&XKEY,
+		&K_encr,
+		&K_aut,
+		&master_session_key);
+	if (status != eap_status_ok)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+
+	// - - - - - - - - - - - - - - - - - - - - - - - -
+
+	m_use_result_indication = m_allow_use_result_indication;
+
+	if (m_use_result_indication == true)
+	{
+		// We support use of protected success indications.
+		status = add_simple_payload(
+			&gsmsim_response,
+			EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+			gsmsim_response.get_header_length(),
+			&gsmsim_data_offset,
+			&gsmsim_data_free,
+			&packet_buffer_free,
+			&packet_buffer_offset,
+			gsmsim_payload_AT_RESULT_IND);
+		if (status != eap_status_ok)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+	}
+
+	// -   -   -   -   -   -   -   -   -   -   -   -
+
+	status = add_n_rand_payload(
+		&gsmsim_response,
+		EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+		gsmsim_response.get_header_length(),
+		&gsmsim_data_offset,
+		&gsmsim_data_free,
+		&packet_buffer_free,
+		&packet_buffer_offset,
+		m_triplets);
+	if (status != eap_status_ok)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+
+	// -   -   -   -   -   -   -   -   -   -   -   -
+
+	u8_t *MAC_data = 0;
+	u32_t MAC_data_length = 0u;
+	eap_type_gsmsim_MAC_attributes_c MAC_attributes;
+
+	if (m_use_pseudonym_identity == true
+		|| m_use_reauthentication_identity == true)
+	{
+		u32_t saved_gsmsim_data_offset = gsmsim_data_offset;
+		u32_t saved_gsmsim_data_free = gsmsim_data_free;
+		u32_t saved_packet_buffer_offset = packet_buffer_offset;
+		u32_t saved_packet_buffer_free = packet_buffer_free;
+
+		crypto_aes_c aes(m_am_tools);
+
+		if (aes.get_is_valid() == false)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, eap_status_allocation_error);
+		}
+
+		status = m_am_type_gsmsim->generate_encryption_IV(
+			m_IV.get_payload_buffer(),
+			aes.get_block_size());
+		if (status != eap_status_ok)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+
+
+		status = add_variable_payload(
+			&gsmsim_response,
+			EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+			gsmsim_response.get_header_length(),
+			&gsmsim_data_offset,
+			&gsmsim_data_free,
+			&packet_buffer_free,
+			&packet_buffer_offset,
+			m_IV.get_payload_buffer(),
+			gsmsim_payload_AT_IV);
+		if (status != eap_status_ok)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+
+
+		// Encrypted data.
+		{
+			gsmsim_payload_AT_header_c gp_encrypted_data(
+				m_am_tools,
+				gsmsim_response.get_data_offset(
+					gsmsim_data_offset, 
+					gsmsim_data_free),
+				gsmsim_data_free);
+			if (gp_encrypted_data.get_is_valid() == false)
+			{
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_parameter);
+			}
+
+			// Initialize the length of encrypted data to maximum length.
+			// Later this will be set to correct length.
+			gp_encrypted_data.reset_header(gsmsim_payload_AT_header_c::get_max_payload_data_length());
+			gp_encrypted_data.set_current_payload(gsmsim_payload_AT_ENCR_DATA);
+
+			update_payload_indexes(
+				EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+				gsmsim_response.get_header_length(),
+				gp_encrypted_data.get_header_length(),
+				&gsmsim_data_offset,
+				&gsmsim_data_free,
+				&packet_buffer_offset,
+				&packet_buffer_free);
+
+			u32_t encrypted_data_offset_begin = packet_buffer_offset;
+
+			// -   -   -   -   -   -   -   -   -   -   -   -
+
+			if (m_use_pseudonym_identity == true)
+			{
+				status = m_am_type_gsmsim->generate_pseudonym_id(
+					&m_send_network_id,
+					&m_IMSI,
+					&m_pseudonym,
+					EAP_TYPE_GSMSIM_MAX_NAI_LENGTH);
+				if (status == eap_status_ok)
+				{
+					status = add_pseudonym_or_imsi_payload(
+						&gsmsim_response,
+						EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+						gsmsim_response.get_header_length(),
+						&gsmsim_data_offset,
+						&gsmsim_data_free,
+						&packet_buffer_free,
+						&packet_buffer_offset,
+						&m_pseudonym,
+						gsmsim_payload_AT_NEXT_PSEUDONYM);
+					if (status != eap_status_ok)
+					{
+						EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+						return EAP_STATUS_RETURN(m_am_tools, status);
+					}
+				}
+			}
+
+			// -   -   -   -   -   -   -   -   -   -   -   -
+
+			if (m_use_reauthentication_identity == true)
+			{
+				status = m_am_type_gsmsim->generate_reauthentication_id(
+					&m_send_network_id,
+					&m_IMSI,
+					&m_reauthentication_identity,
+					EAP_TYPE_GSMSIM_MAX_NAI_LENGTH);
+				if (status == eap_status_ok)
+				{
+					status = add_pseudonym_or_imsi_payload(
+						&gsmsim_response,
+						EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+						gsmsim_response.get_header_length(),
+						&gsmsim_data_offset,
+						&gsmsim_data_free,
+						&packet_buffer_free,
+						&packet_buffer_offset,
+						&m_reauthentication_identity,
+						gsmsim_payload_AT_NEXT_REAUTH_ID);
+					if (status != eap_status_ok)
+					{
+						EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+						return EAP_STATUS_RETURN(m_am_tools, status);
+					}
+				}
+			}
+
+			// -   -   -   -   -   -   -   -   -   -   -   -
+
+			u32_t plain_text_length = packet_buffer_offset - encrypted_data_offset_begin;
+
+			if (plain_text_length > 0ul)
+			{
+				status = add_padding_payload(
+					&gsmsim_response,
+					EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+					gsmsim_response.get_header_length(),
+					&gsmsim_data_offset,
+					&gsmsim_data_free,
+					&packet_buffer_free,
+					&packet_buffer_offset,
+					plain_text_length
+					);
+				if (status != eap_status_ok)
+				{
+					EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+					return EAP_STATUS_RETURN(m_am_tools, status);
+				}
+
+				// Re calculate after adding the padding.
+				plain_text_length = packet_buffer_offset - encrypted_data_offset_begin;
+
+				gp_encrypted_data.set_data_length(
+					static_cast<u16_t>(plain_text_length));
+
+				// -   -   -   -   -   -   -   -   -   -   -   -
+
+				status = encrypt_DATA_payload(
+					gp_encrypted_data.get_data(gp_encrypted_data.get_data_length()),
+					gp_encrypted_data.get_data_length(),
+					m_IV.get_payload_buffer(),
+					&K_encr);
+				if (status != eap_status_ok)
+				{
+					EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+					return EAP_STATUS_RETURN(m_am_tools, status);
+				}
+
+				EAP_GSMSIM_TRACE_PAYLOAD("Payload added", &gp_encrypted_data);
+			}
+			else
+			{
+				// No encrypted data, remove AT_ENCR_DATA header.
+				gsmsim_data_offset = saved_gsmsim_data_offset;
+				gsmsim_data_free = saved_gsmsim_data_free;
+				packet_buffer_offset = saved_packet_buffer_offset;
+				packet_buffer_free = saved_packet_buffer_free;
+			}
+		}
+	}
+
+	// -   -   -   -   -   -   -   -   -   -   -   -
+
+	status = add_mac_payload(
+		&gsmsim_response,
+		EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+		gsmsim_response.get_header_length(),
+		&gsmsim_data_offset,
+		&gsmsim_data_free,
+		&packet_buffer_free,
+		&packet_buffer_offset,
+		&MAC_data,
+		&MAC_data_length);
+	if (status != eap_status_ok)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+
+	// -   -   -   -   -   -   -   -   -   -   -   -
+
+	gsmsim_response.set_data_length(
+		gsmsim_data_offset,
+		m_use_eap_expanded_type);
+
+	gsmsim_initial_reply.set_data_length(packet_buffer_offset);
+
+	EAP_ASSERT_ALWAYS(
+		m_gsmsim_header_offset+gsmsim_response.get_header_length()+gsmsim_response.get_data_length()
+		== packet_buffer_offset);
+
+	// -   -   -   -   -   -   -   -   -   -   -   -
+
+	MAC_attributes.init(
+		MAC_data,
+		MAC_data_length,
+		gsmsim_response.get_header_buffer(gsmsim_response.get_length()),
+		gsmsim_response.get_length());
+
+	status = create_message_authentication_code(
+		&MAC_attributes,
+		gsmsim_response.get_subtype(),
+		gsmsim_response.get_code(),
+		&K_aut);
+	if (status != eap_status_ok)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+
+	// - - - - - - - - - - - - - - - - - - - - - - - -
+
+	gsmsim_response.set_data_length(
+		gsmsim_data_offset,
+		m_use_eap_expanded_type);
+
+	gsmsim_initial_reply.set_data_length(packet_buffer_offset);
+
+	EAP_ASSERT_ALWAYS(
+		m_gsmsim_header_offset+gsmsim_response.get_header_length()+gsmsim_response.get_data_length()
+		== packet_buffer_offset);
+
+	// - - - - - - - - - - - - - - - - - - - - - - - -
+
+	status = packet_send(
+		&m_send_network_id,
+		&gsmsim_initial_reply,
+		m_gsmsim_header_offset,
+		gsmsim_response.get_header_length()+gsmsim_response.get_data_length(),
+		EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH
+		);
+
+	if (status == eap_status_ok)
+	{
+		// Store keys.
+		status = m_XKEY.set_copy_of_buffer(&XKEY);
+		if (status != eap_status_ok)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+		status = m_K_encr.set_copy_of_buffer(&K_encr);
+		if (status != eap_status_ok)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+		status = m_K_aut.set_copy_of_buffer(&K_aut);
+		if (status != eap_status_ok)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+		status = m_master_session_key.set_copy_of_buffer(&master_session_key);
+		if (status != eap_status_ok)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+	}
+
+	// - - - - - - - - - - - - - - - - - - - - - - - -
+
+	EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+	return EAP_STATUS_RETURN(m_am_tools, status);
+}
+
+//--------------------------------------------------
+
+//
+EAP_FUNC_EXPORT eap_status_e eap_type_gsmsim_c::send_gsmsim_notification_request(
+	const eap_gsmsim_notification_codes_e notification_code,
+	const bool add_at_counter_attribute)
+{
+	EAP_TRACE_BEGIN(m_am_tools, TRACE_FLAGS_DEFAULT);
+
+	EAP_TRACE_DEBUG(
+		m_am_tools, 
+		TRACE_FLAGS_DEFAULT, 
+		(EAPL("send: GSMSIM-type %10s, %s, state %2d=%s, notification_code = %d\n"),
+		 EAPL("send_gsmsim_notification_request"),
+		 (m_is_client) ? EAPL("client") : EAPL("server"),
+		 m_state,
+		 get_state_string(),
+		 notification_code
+		 ));
+
+	eap_buf_chain_wr_c eap_notification_packet(
+		eap_write_buffer, 
+		m_am_tools, 
+		EAP_MAX_LOCAL_PACKET_BUFFER_LENGTH);
+
+	if (eap_notification_packet.get_is_valid() == false)
+	{
+		EAP_TRACE_ERROR(m_am_tools, TRACE_FLAGS_DEFAULT, (EAPL("packet buffer corrupted.\n")));
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_allocation_error);
+	}
+
+#if defined(USE_EAP_TYPE_GSMSIM_OWN_RE_TRANSMISSION)
+	if (m_is_client == true
+		&& m_client_responds_retransmitted_packets == true)
+	{
+		// We do not wan't lower layers do re-transmissions behalf of us.
+		// This means GSMSIM does process every re-transmitted EAP-Request.
+		eap_notification_packet.set_do_packet_retransmission(false);
+	}
+#endif //#if defined(USE_EAP_TYPE_GSMSIM_OWN_RE_TRANSMISSION)
+
+	EAP_ASSERT_ALWAYS(EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH >= (m_gsmsim_header_offset+m_trailer_length));
+	u32_t packet_buffer_free = EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH-m_trailer_length;
+	u32_t packet_buffer_offset = 0u;
+
+	if (m_gsmsim_header_offset+m_MTU < packet_buffer_free)
+	{
+		packet_buffer_free = m_gsmsim_header_offset+m_MTU;
+	}
+
+	gsmsim_header_c gsmsim_response(
+		m_am_tools,
+		eap_notification_packet.get_data_offset(
+			m_gsmsim_header_offset,
+			(packet_buffer_free-m_gsmsim_header_offset)),
+		(packet_buffer_free-m_gsmsim_header_offset));
+
+	if (gsmsim_response.get_is_valid() == false)
+	{
+		EAP_TRACE_ERROR(m_am_tools, TRACE_FLAGS_DEFAULT, (EAPL("packet_send: packet buffer corrupted.\n")));
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+	}
+
+	m_last_eap_identifier = static_cast<u8_t>(m_last_eap_identifier+1u);
+
+	gsmsim_response.reset_header(
+		static_cast<u16_t>(packet_buffer_free-m_gsmsim_header_offset),
+		m_use_eap_expanded_type);
+	gsmsim_response.set_length(
+		static_cast<u16_t>(packet_buffer_free-m_gsmsim_header_offset),
+		m_use_eap_expanded_type);
+	gsmsim_response.set_code(eap_code_request);
+	gsmsim_response.set_identifier(m_last_eap_identifier);
+	gsmsim_response.set_type(
+		eap_type_gsmsim,
+		m_use_eap_expanded_type);
+	gsmsim_response.set_subtype(gsmsim_subtype_Notification);
+
+
+	update_buffer_indexes(
+		EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+		m_gsmsim_header_offset+gsmsim_response.get_header_length(),
+		&packet_buffer_offset,
+		&packet_buffer_free);
+
+	// - - - - - - - - - - - - - - - - - - - - - - - -
+
+	u32_t gsmsim_data_free = packet_buffer_free;
+	u32_t gsmsim_data_offset = 0u;
+
+	eap_status_e status = add_notification_payload(
+		&gsmsim_response,
+		EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+		gsmsim_response.get_header_length(),
+		&gsmsim_data_offset,
+		&gsmsim_data_free,
+		&packet_buffer_free,
+		&packet_buffer_offset,
+		notification_code);
+	if (status != eap_status_ok)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+
+
+	eap_variable_data_c * K_aut = 0;
+	eap_variable_data_c orig_K_aut(m_am_tools);
+
+	if (get_gsmsim_notification_code_P_bit(notification_code) == false)
+	{
+		u8_t *MAC_data = 0;
+		u32_t MAC_data_length = 0u;
+		eap_type_gsmsim_MAC_attributes_c MAC_attributes;
+
+		if (add_at_counter_attribute == true)
+		{
+			// If EAP-Request/SIM/Notification is used on fast a re-authentication
+			// exchange, and if the P bit in AT_NOTIFICATION is set to zero, then
+			// AT_COUNTER is used for replay protection. In this case, the
+			// AT_ENCR_DATA and AT_IV attributes MUST be included, and the
+			// encapsulated plaintext attributes MUST include the AT_COUNTER
+			// attribute. The counter value included in AT_COUNTER MUST be the same
+			// as in the EAP-Request/SIM/Re-authentication packet on the same fast
+			// re-authentication exchange.
+
+			// - - - - - - - - - - - - - - - - - - - - - - - -
+
+			eap_variable_data_c orig_XKEY(m_am_tools);
+			eap_variable_data_c orig_K_encr(m_am_tools);
+			u32_t reauth_counter = 0u;
+
+			// In order to use re-authentication, the client and the server need to
+			// store the following values: original XKEY, K_aut, K_encr, latest
+			// counter value and the next re-authentication identity.
+			status = m_am_type_gsmsim->query_reauth_parameters(
+				&orig_XKEY,
+				&orig_K_aut,
+				&orig_K_encr,
+				&reauth_counter);
+			if (status != eap_status_ok)
+			{
+				restore_saved_previous_state();
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, status);
+			}
+
+			EAP_TRACE_DEBUG(
+				m_am_tools,
+				TRACE_FLAGS_DEFAULT,
+				(EAPL("eap_type_gsmsim_c::send_gsmsim_notification_request(): %s, m_saved_reauth_counter %d.\n"),
+				 (m_is_client == true ? "client": "server"),
+				 reauth_counter));
+
+			K_aut = &orig_K_aut;
+
+			// -   -   -   -   -   -   -   -   -   -   -   -
+
+			crypto_aes_c aes(m_am_tools);
+
+			if (aes.get_is_valid() == false)
+			{
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, eap_status_allocation_error);
+			}
+
+			status = m_am_type_gsmsim->generate_encryption_IV(
+				m_IV.get_payload_buffer(),
+				aes.get_block_size());
+			if (status != eap_status_ok)
+			{
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, status);
+			}
+
+
+			status = add_variable_payload(
+				&gsmsim_response,
+				EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+				gsmsim_response.get_header_length(),
+				&gsmsim_data_offset,
+				&gsmsim_data_free,
+				&packet_buffer_free,
+				&packet_buffer_offset,
+				m_IV.get_payload_buffer(),
+				gsmsim_payload_AT_IV);
+			if (status != eap_status_ok)
+			{
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, status);
+			}
+
+
+			// Encrypted data.
+			{
+				gsmsim_payload_AT_header_c gp_encrypted_data(
+					m_am_tools,
+					gsmsim_response.get_data_offset(
+						gsmsim_data_offset, 
+						gsmsim_data_free),
+					gsmsim_data_free);
+				if (gsmsim_response.get_is_valid() == false)
+				{
+					EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+					return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_parameter);
+				}
+
+				// Initialize the length of encrypted data to maximum length.
+				// Later this will be set to correct length.
+				gp_encrypted_data.reset_header(gsmsim_payload_AT_header_c::get_max_payload_data_length());
+				gp_encrypted_data.set_current_payload(gsmsim_payload_AT_ENCR_DATA);
+
+				update_payload_indexes(
+					EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+					gsmsim_response.get_header_length(),
+					gp_encrypted_data.get_header_length(),
+					&gsmsim_data_offset,
+					&gsmsim_data_free,
+					&packet_buffer_offset,
+					&packet_buffer_free);
+
+				u32_t encrypted_data_offset_begin = packet_buffer_offset;
+
+				// -   -   -   -   -   -   -   -   -   -   -   -
+
+				status = add_counter_payload(
+					&gsmsim_response,
+					EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+					gsmsim_response.get_header_length(),
+					&gsmsim_data_offset,
+					&gsmsim_data_free,
+					&packet_buffer_free,
+					&packet_buffer_offset,
+					static_cast<u16_t>(reauth_counter));
+				if (status != eap_status_ok)
+				{
+					EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+					return EAP_STATUS_RETURN(m_am_tools, status);
+				}
+
+				// -   -   -   -   -   -   -   -   -   -   -   -
+
+				status = add_padding_payload(
+					&gsmsim_response,
+					EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+					gsmsim_response.get_header_length(),
+					&gsmsim_data_offset,
+					&gsmsim_data_free,
+					&packet_buffer_free,
+					&packet_buffer_offset,
+					(packet_buffer_offset - encrypted_data_offset_begin) // Length of the plain text.
+					);
+				if (status != eap_status_ok)
+				{
+					EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+					return EAP_STATUS_RETURN(m_am_tools, status);
+				}
+
+				gp_encrypted_data.set_data_length(
+					static_cast<u16_t>(packet_buffer_offset - encrypted_data_offset_begin));
+
+				// -   -   -   -   -   -   -   -   -   -   -   -
+
+				status = encrypt_DATA_payload(
+					gp_encrypted_data.get_data(gp_encrypted_data.get_data_length()),
+					gp_encrypted_data.get_data_length(),
+					m_IV.get_payload_buffer(),
+					&orig_K_encr);
+				if (status != eap_status_ok)
+				{
+					EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+					return EAP_STATUS_RETURN(m_am_tools, status);
+				}
+
+				EAP_GSMSIM_TRACE_PAYLOAD("Payload added", &gp_encrypted_data);
+			}
+
+		}
+		else
+		{
+			K_aut = &m_K_aut;
+		} // if (add_counter_payload == true)
+
+		// -   -   -   -   -   -   -   -   -   -   -   -
+
+		// Add AT_MAC attribute.
+		status = add_mac_payload(
+			&gsmsim_response,
+			EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH,
+			gsmsim_response.get_header_length(),
+			&gsmsim_data_offset,
+			&gsmsim_data_free,
+			&packet_buffer_free,
+			&packet_buffer_offset,
+			&MAC_data,
+			&MAC_data_length);
+		if (status != eap_status_ok)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+
+		// -   -   -   -   -   -   -   -   -   -   -   -
+
+		gsmsim_response.set_data_length(
+			gsmsim_data_offset,
+			m_use_eap_expanded_type);
+
+		eap_notification_packet.set_data_length(packet_buffer_offset);
+
+		EAP_ASSERT_ALWAYS(
+			m_gsmsim_header_offset+gsmsim_response.get_header_length()+gsmsim_response.get_data_length()
+			== packet_buffer_offset);
+
+		// -   -   -   -   -   -   -   -   -   -   -   -
+
+		MAC_attributes.init(
+			MAC_data,
+			MAC_data_length,
+			gsmsim_response.get_header_buffer(gsmsim_response.get_length()),
+			gsmsim_response.get_length());
+
+		status = create_message_authentication_code(
+			&MAC_attributes,
+			gsmsim_response.get_subtype(),
+			gsmsim_response.get_code(),
+			K_aut);
+		if (status != eap_status_ok)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+
+	}
+	else
+	{
+		gsmsim_response.set_data_length(
+			gsmsim_data_offset,
+			m_use_eap_expanded_type);
+
+		eap_notification_packet.set_data_length(packet_buffer_offset);
+
+		EAP_ASSERT_ALWAYS(
+			m_gsmsim_header_offset+gsmsim_response.get_header_length()+gsmsim_response.get_data_length()
+			== packet_buffer_offset);
+	}
+
+	// - - - - - - - - - - - - - - - - - - - - - - - -
+
+	eap_notification_packet.set_data_length(packet_buffer_offset);
+
+	EAP_TRACE_DATA_DEBUG(m_am_tools, TRACE_FLAGS_DEFAULT, (EAPL("    send: EAP-Response/Notification packet"),
+		gsmsim_response.get_header_buffer(gsmsim_response.get_length()),
+		gsmsim_response.get_length()));
+
+	status = packet_send(
+		&m_send_network_id,
+		&eap_notification_packet,
+		m_gsmsim_header_offset,
+		gsmsim_response.get_length(),
+		EAP_TYPE_GSMSIM_LOCAL_PACKET_BUFFER_LENGTH
+		);
+
+	if (status == eap_status_ok)
+	{
+	}
+
+	// - - - - - - - - - - - - - - - - - - - - - - - -
+
+	EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+	return EAP_STATUS_RETURN(m_am_tools, status);
+}
+
+
+//--------------------------------------------------
+
+//
+EAP_FUNC_EXPORT eap_status_e eap_type_gsmsim_c::query_SIM_triplets(
+		eap_type_gsmsim_identity_type * const identity_type)
+{
+	EAP_TRACE_BEGIN(m_am_tools, TRACE_FLAGS_DEFAULT);
+
+	eap_type_sim_triplet_array_c triplets(m_am_tools);
+
+	set_state(eap_type_gsmsim_state_pending_triplet_query);
+
+	eap_status_e status = m_am_type_gsmsim->query_SIM_triplets(
+		false,
+		&m_identity, // This is username part from payload AT_IDENTITY.
+		&m_IMSI, // This is the real IMSI. If this is uninitialized get_identity() must be initialized, imsi will be initialized after this call is complete.
+		&triplets,
+		identity_type);
+
+	if (status == eap_status_pending_request)
+	{
+		// This is pending query, that will be completed by complete_SIM_triplets() call.
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+	else if (status == eap_status_completed_request)
+	{
+		// This query was already completed by complete_SIM_triplets() call.
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+	else if (status != eap_status_ok)
+	{
+		// Some error occurred.
+		restore_saved_previous_state();
+
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+
+	set_triplets(triplets.copy());
+	if (m_triplets == 0
+		|| m_triplets->get_triplet_count() == 0)
+	{
+		restore_saved_previous_state();
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_allocation_error);
+	}
+
+	EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+	return EAP_STATUS_RETURN(m_am_tools, status);
+}
+
+//--------------------------------------------------
+
+//
+EAP_FUNC_EXPORT eap_status_e eap_type_gsmsim_c::complete_SIM_triplets(
+	eap_type_sim_triplet_array_c * const triplets,
+	const eap_variable_data_c * const IMSI,
+	const eap_gsmsim_triplet_status_e triplet_status,
+	const eap_type_gsmsim_identity_type identity_type,
+	const eap_status_e completion_status)
+{
+	EAP_TRACE_BEGIN(m_am_tools, TRACE_FLAGS_DEFAULT);
+
+	EAP_TRACE_DEBUG(
+		m_am_tools, 
+		TRACE_FLAGS_DEFAULT|TRACE_TEST_VECTORS, 
+		(EAPL("eap_type_gsmsim_c::complete_SIM_triplets(): identity_type %d=%s, requested identity payload is %d=%s, state %d=%s\n"),
+		 identity_type,
+		 get_identity_string(identity_type),
+		 m_start_response_includes_identity,
+		 gsmsim_payload_AT_header_c::get_payload_AT_string(m_start_response_includes_identity),
+		 m_state,
+		 get_state_string()));
+
+	if (completion_status != eap_status_ok
+		|| triplets == 0)
+	{
+		set_state(eap_type_gsmsim_state_failure);
+
+		// The eap_status_process_general_error error value is more important
+		// than return value of set_session_timeout().
+		get_type_partner()->set_session_timeout(0ul);
+
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_process_general_error);
+	}
+
+
+	if (m_state != eap_type_gsmsim_state_pending_triplet_query)
+	{
+		// Authentication is terminated or state is wrong. Cannot continue.
+		set_state(eap_type_gsmsim_state_failure);
+
+		// The eap_status_handler_does_not_exists_error error value is more important
+		// than return value of set_session_timeout().
+		get_type_partner()->set_session_timeout(0ul);
+
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_handler_does_not_exists_error);
+	}
+
+	eap_status_e status = eap_status_process_general_error;
+
+	if (m_identity_type != GSMSIM_IDENTITY_TYPE_RE_AUTH_ID)
+	{
+		set_identity_type(identity_type);
+	}
+
+	if (m_identity_type == GSMSIM_IDENTITY_TYPE_IMSI_ID
+		&& IMSI->get_is_valid_data() == true)
+	{
+		status = m_IMSI.set_copy_of_buffer(IMSI);
+		if (status != eap_status_ok)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+	}
+
+	if (triplet_status == eap_gsmsim_triplet_status_ok)
+	{
+		// First check the identity type is correct.
+		if ((m_identity_type == GSMSIM_IDENTITY_TYPE_IMSI_ID
+				&& (m_start_response_includes_identity == gsmsim_payload_AT_PERMANENT_ID_REQ
+					|| m_start_response_includes_identity == gsmsim_payload_AT_FULLAUTH_ID_REQ
+					|| m_start_response_includes_identity == gsmsim_payload_AT_ANY_ID_REQ))
+			|| (m_identity_type == GSMSIM_IDENTITY_TYPE_PSEUDONYM_ID
+				&& (m_start_response_includes_identity == gsmsim_payload_AT_FULLAUTH_ID_REQ
+					|| m_start_response_includes_identity == gsmsim_payload_AT_ANY_ID_REQ))
+			|| (m_identity_type == GSMSIM_IDENTITY_TYPE_RE_AUTH_ID
+				&& m_start_response_includes_identity == gsmsim_payload_AT_ANY_ID_REQ)
+			|| m_start_response_includes_identity == gsmsim_payload_NONE)
+		{
+			// OK, correct identity received.
+			EAP_TRACE_DEBUG(
+				m_am_tools, 
+				TRACE_FLAGS_DEFAULT, 
+				(EAPL("eap_type_gsmsim_c::complete_SIM_triplets(): OK\n")));
+		}
+		else
+		{
+			EAP_TRACE_ERROR(
+				m_am_tools, 
+				TRACE_FLAGS_GSMSIM_ERROR, 
+				(EAPL("ERROR: eap_type_gsmsim_c::complete_SIM_triplets(): ")
+				 EAPL("EAP-identity is wrong, state %d=%s.\n"),
+				 m_state, get_state_string()));
+
+			if (m_start_response_includes_identity == gsmsim_payload_AT_PERMANENT_ID_REQ)
+			{
+				EAP_TRACE_DEBUG(
+					m_am_tools, 
+					TRACE_FLAGS_GSMSIM_ERROR, 
+					(EAPL("ERROR: eap_type_gsmsim_c::complete_SIM_triplets(): ")
+					 EAPL("permanent identity was required, %d=%s was get.\n"),
+					 m_identity_type,
+					 get_identity_string(m_identity_type)));
+			}
+			else if (m_start_response_includes_identity == gsmsim_payload_AT_FULLAUTH_ID_REQ)
+			{
+				EAP_TRACE_DEBUG(
+					m_am_tools, 
+					TRACE_FLAGS_GSMSIM_ERROR, 
+					(EAPL("ERROR: eap_type_gsmsim_c::complete_SIM_triplets(): ")
+					 EAPL("full authentication identity was required, %d=%s was get.\n"),
+					 m_identity_type,
+					 get_identity_string(m_identity_type)));
+			}
+			else if (m_start_response_includes_identity == gsmsim_payload_AT_ANY_ID_REQ)
+			{
+				EAP_TRACE_DEBUG(
+					m_am_tools, 
+					TRACE_FLAGS_GSMSIM_ERROR, 
+					(EAPL("ERROR: eap_type_gsmsim_c::complete_SIM_triplets(): ")
+					 EAPL("any identity was required, %d=%s was get.\n"),
+					 m_identity_type,
+					 get_identity_string(m_identity_type)));
+			}
+			else
+			{
+				EAP_TRACE_ERROR(
+					m_am_tools, 
+					TRACE_FLAGS_GSMSIM_ERROR, 
+					(EAPL("ERROR: eap_type_gsmsim_c::complete_SIM_triplets(): ")
+					 EAPL("no special identity was required, %d=%s was get.\n"),
+					 m_identity_type,
+					 get_identity_string(m_identity_type)));
+			}
+			
+			EAP_TRACE_DATA_DEBUG(m_am_tools, TRACE_FLAGS_DEFAULT, (EAPL("ERROR, wrong identity"),
+				m_NAI.get_data(),
+				m_NAI.get_data_length()));
+
+			restore_saved_previous_state();
+
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_eap_identity);
+		}
+
+		if (m_IMSI.get_is_valid_data() == false
+			&& IMSI != &m_IMSI)
+		{
+			// We must copy queried IMSI.
+			status = m_IMSI.set_copy_of_buffer(IMSI);
+			if (status != eap_status_ok)
+			{
+				restore_saved_previous_state();
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, status);
+			}
+		}
+
+		set_triplets(triplets->copy());
+		if (m_triplets == 0
+			|| m_triplets->get_triplet_count() == 0)
+		{
+			restore_saved_previous_state();
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, eap_status_allocation_error);
+		}
+
+		u8_t local_eap_identifier;
+
+		if (m_saved_previous_state == eap_type_gsmsim_state_waiting_for_challenge_response)
+		{
+			// Do not increase EAP-Identifier, this was re-transmission.
+			local_eap_identifier = m_last_eap_identifier;
+		}
+		else
+		{
+			local_eap_identifier = static_cast<u8_t>(m_last_eap_identifier+1u);
+		}
+
+		status = send_challenge_request_message(
+			local_eap_identifier);
+		if (status != eap_status_ok)
+		{
+			restore_saved_previous_state();
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+
+		m_last_eap_identifier = local_eap_identifier;
+		set_state(eap_type_gsmsim_state_waiting_for_challenge_response);
+	}
+	else
+	{
+		// Error occurred in tripler query.
+		// We must send EAP-Notification message.
+		// 
+		// eap_gsmsim_notification_no_F_no_P_users_calls_are_barred and eap_gsmsim_notification_no_F_no_P_user_has_not_subscribed_to_the_requested_service cannot be used because P bit is not set.
+		m_gsmsim_notification_code = eap_gsmsim_notification_no_F_P_set_general_failure;
+
+		status = initialize_notification_message();
+
+		m_last_eap_identifier = static_cast<u8_t>(m_last_eap_identifier+1u);
+
+		set_state(eap_type_gsmsim_state_waiting_for_notification_response_failure);
+	}
+
+
+	EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+	return EAP_STATUS_RETURN(m_am_tools, status);
+}
+
+//--------------------------------------------------
+
+EAP_FUNC_EXPORT bool eap_type_gsmsim_c::randomly_refuse_eap_identity()
+{
+	bool skip_query_imsi_from_username = false;
+
+	if (m_gsmsim_test_version == true
+		&& m_gsmsim_randomly_refuse_eap_identity == true)
+	{
+		crypto_random_c rand(m_am_tools);
+
+		if (rand.get_is_valid() == false)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return false;
+		}
+
+		u32_t random_guard;
+
+		eap_status_e status = rand.get_rand_bytes(
+			reinterpret_cast<u8_t *>(&random_guard),
+			sizeof(random_guard));
+		if (status != eap_status_ok)
+		{
+			return false;
+		}
+
+		if ((random_guard % 2) == 0)
+		{
+			// Note, this is just for testing.
+			skip_query_imsi_from_username = true;
+
+			EAP_TRACE_DEBUG(
+				m_am_tools, 
+				TRACE_FLAGS_DEFAULT, 
+				(EAPL("TEST: eap_type_gsmsim_c::randomly_refuse_eap_identity(): ")
+				 EAPL("randomly fails EAP-Identity.\n")));
+		}
+	}
+
+	return skip_query_imsi_from_username;
+}
+
+//--------------------------------------------------
+
+//
+EAP_FUNC_EXPORT eap_status_e eap_type_gsmsim_c::handle_identity_response_message(
+	eap_header_rd_c * const eap_header,
+	const u32_t gsmsim_packet_length)
+{
+	eap_status_e status = eap_status_process_general_error;
+
+#if defined(USE_EAP_GSMSIM_VERIFY_STATES)
+	const eap_type_gsmsim_state_variable_e gsmsim_identity_response_states_1[] =
+	{
+		eap_type_gsmsim_state_waiting_for_identity_response,
+		eap_type_gsmsim_state_waiting_for_start_response,
+		eap_type_gsmsim_state_waiting_for_start_response_with_at_any_identity,
+		eap_type_gsmsim_state_waiting_for_start_response_with_at_full_auth_identity,
+		eap_type_gsmsim_state_waiting_for_start_response_with_at_permanent_identity,
+	};
+
+	const eap_type_gsmsim_state_variable_e gsmsim_identity_response_states_2[] =
+	{
+		eap_type_gsmsim_state_waiting_for_start_response,
+		eap_type_gsmsim_state_waiting_for_start_response_with_at_any_identity,
+		eap_type_gsmsim_state_waiting_for_start_response_with_at_full_auth_identity,
+		eap_type_gsmsim_state_waiting_for_start_response_with_at_permanent_identity,
+	};
+
+	if (verify_states(gsmsim_identity_response_states_1, GSMSIM_STATE_COUNT(gsmsim_identity_response_states_1)) == true
+		// In test version new authentication could start from this state.
+		|| (m_gsmsim_test_version == true
+			&& m_state == eap_type_gsmsim_state_success) // This one is for testing purposes.
+		)
+#else
+	if (m_state == eap_type_gsmsim_state_waiting_for_identity_response
+		|| m_state == eap_type_gsmsim_state_waiting_for_start_response
+		|| m_state == eap_type_gsmsim_state_waiting_for_start_response_with_at_any_identity
+		|| m_state == eap_type_gsmsim_state_waiting_for_start_response_with_at_full_auth_identity
+		|| m_state == eap_type_gsmsim_state_waiting_for_start_response_with_at_permanent_identity
+		// In test version new authentication could start from this state.
+		|| (m_gsmsim_test_version == true
+			&& m_state == eap_type_gsmsim_state_success) // This one is for testing purposes.
+		)
+#endif //#if defined(USE_EAP_GSMSIM_VERIFY_STATES)
+	{
+		// OK correct state.
+	}
+	else
+	{
+		// Wrong state, dischard packet.
+		EAP_TRACE_ERROR(
+			m_am_tools, 
+			TRACE_FLAGS_GSMSIM_ERROR, 
+			(EAPL("ERROR: eap_type_gsmsim_c::handle_identity_response_message(): ")
+			 EAPL("EAP-Response/Identity received in wrong state %d=%s. This EAP-packet is dropped.\n"),
+			 m_state, get_state_string()));
+		EAP_TRACE_ERROR(
+			m_am_tools, 
+			TRACE_FLAGS_GSMSIM_ERROR, 
+			(EAPL("ERROR: erroneous EAP packet: code=0x%02x, ")
+			 EAPL("identifier=0x%02x, length=0x%04x, type=0x%08x, client %d\n"),
+			 eap_header->get_code(),
+			 eap_header->get_identifier(),
+			 eap_header->get_length(),
+			 convert_eap_type_to_u32_t(eap_header->get_type()),
+			 get_is_client()));
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_process_illegal_packet_error);
+	}
+
+	if (m_check_identifier_of_eap_identity_response == true)
+	{
+		if (m_state == eap_type_gsmsim_state_waiting_for_identity_response
+		&& eap_header->get_identifier() != m_last_eap_identifier)
+		{
+			// Wrong EAP-Identifier in this state.
+			EAP_TRACE_ERROR(
+				m_am_tools, 
+				TRACE_FLAGS_GSMSIM_ERROR, 
+				(EAPL("ERROR: eap_type_gsmsim_c::handle_identity_response_message(): ")
+				 EAPL("EAP-Identifier 0x%02x is wrong (0x%02x is correct) ")
+				 EAPL("in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+				 eap_header->get_identifier(),
+				 m_last_eap_identifier, 
+				 m_state,
+				 get_state_string()));
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_eap_identity);
+		}
+#if defined(USE_EAP_GSMSIM_VERIFY_STATES)
+		else if (verify_states(gsmsim_identity_response_states_2, GSMSIM_STATE_COUNT(gsmsim_identity_response_states_2)) == true
+				 && eap_header->get_identifier() != m_last_eap_identifier-1u)
+#else
+		else if ((m_state == eap_type_gsmsim_state_waiting_for_start_response
+				  || m_state == eap_type_gsmsim_state_waiting_for_start_response_with_at_any_identity
+				  || m_state == eap_type_gsmsim_state_waiting_for_start_response_with_at_full_auth_identity
+				  || m_state == eap_type_gsmsim_state_waiting_for_start_response_with_at_permanent_identity
+				  )
+				 && eap_header->get_identifier() != m_last_eap_identifier-1u)
+#endif //#if defined(USE_EAP_GSMSIM_VERIFY_STATES)
+		{
+			// Wrong EAP-Identifier in this state.
+			EAP_TRACE_ERROR(
+				m_am_tools, 
+				TRACE_FLAGS_GSMSIM_ERROR, 
+				(EAPL("ERROR: eap_type_gsmsim_c::handle_identity_response_message(): ")
+				 EAPL("EAP-Identifier 0x%02x is wrong (0x%02x is correct) ")
+				 EAPL("in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+				 eap_header->get_identifier(),
+				 m_last_eap_identifier-1u, 
+				 m_state,
+				 get_state_string()));
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_eap_identity);
+		}
+		// In test version new authentication could start from this state.
+		else if (m_gsmsim_test_version == true
+			&& m_state == eap_type_gsmsim_state_success) // This one is for testing purposes.
+		{
+			// NOTE here we can not check the EAP-identifier.
+			EAP_TRACE_ERROR(
+				m_am_tools, 
+				TRACE_FLAGS_DEFAULT, 
+				(EAPL("WARNING: eap_type_gsmsim_c::handle_identity_response_message(): ")
+				 EAPL("EAP-Identifier 0x%02x is not checked in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+				 eap_header->get_identifier(),
+				 m_state,
+				 get_state_string()));
+		}
+	}
+
+	{
+		// This could be first or retransmission request.
+
+		if (eap_header->get_type_data_length() > gsmsim_packet_length)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_eap_identity);
+		}
+
+		status = parse_identity(
+			eap_header->get_type_data(
+				eap_header->get_type_data_length()),
+			eap_header->get_type_data_length());
+		if (status != eap_status_ok)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+
+		EAP_TRACE_DATA_DEBUG(
+			m_am_tools, 
+			TRACE_FLAGS_DEFAULT,
+			(EAPL("GSMSIM received EAP-identity NAI"),
+			 m_NAI.get_data(),
+			 m_NAI.get_data_length()));
+
+		u8_t next_eap_identifier = static_cast<u8_t>(eap_header->get_identifier()+1u);
+
+#if defined(USE_EAP_GSMSIM_VERIFY_STATES)
+		if (verify_states(gsmsim_identity_response_states_2, GSMSIM_STATE_COUNT(gsmsim_identity_response_states_2)) == true)
+#else
+		if (m_state == eap_type_gsmsim_state_waiting_for_start_response
+			|| m_state == eap_type_gsmsim_state_waiting_for_start_response_with_at_any_identity
+			|| m_state == eap_type_gsmsim_state_waiting_for_start_response_with_at_full_auth_identity
+			|| m_state == eap_type_gsmsim_state_waiting_for_start_response_with_at_permanent_identity
+			)
+#endif //#if defined(USE_EAP_GSMSIM_VERIFY_STATES)
+		{
+			// This is retransmission, so the EAP-identifier is not increased.
+			next_eap_identifier = m_last_eap_identifier;
+		}
+		// In test version new authentication could start from this state.
+		else if (m_gsmsim_test_version == true
+			&& m_state == eap_type_gsmsim_state_success) // This one is for testing purposes.
+		{
+			// NOTE here we can not check the EAP-identifier.
+			next_eap_identifier = static_cast<u8_t>(eap_header->get_identifier()+1u);
+			set_state(eap_type_gsmsim_state_waiting_for_identity_response);
+			m_IMSI.reset();
+		}
+
+		save_current_state();
+		set_state(eap_type_gsmsim_state_pending_pseudonym_decode_query);
+
+		eap_type_gsmsim_identity_type identity_type = GSMSIM_IDENTITY_TYPE_NONE;
+
+		if (m_accept_eap_identity_response == true)
+		{
+			if (randomly_refuse_eap_identity() == false)
+			{
+				status = m_am_type_gsmsim->query_imsi_from_username(
+					false,
+					next_eap_identifier,
+					&m_send_network_id,
+					&m_identity,
+					&m_IMSI,
+					&identity_type,
+					eap_type_gsmsim_complete_handle_imsi_from_username);
+			}
+			else
+			{
+				status = eap_status_illegal_eap_identity;
+			}
+
+			if (status == eap_status_pending_request)
+			{
+				// This is pending query, that will be completed by complete_imsi_from_username() call.
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, eap_status_ok);
+			}
+			else if (status == eap_status_completed_request)
+			{
+				// This is already completed by complete_imsi_from_username() call.
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, eap_status_ok);
+			}
+			else if (status != eap_status_ok)
+			{
+				// Identity decoding failed.
+				// We must query IMSI of client.
+
+				if (m_use_manual_username == true)
+				{
+					// We reset the illegal identity.
+					// EAP-SIM/request/start will query identity.
+					m_identity.reset();
+				}
+			}
+			else // status == eap_status_ok
+			{
+				// The query_imsi_from_username() function call was synchronous.
+				// We must call send_start_request_message().
+			}
+		}
+
+
+		{
+			status = handle_imsi_from_username(
+				next_eap_identifier,
+				&m_send_network_id,
+				&m_identity,
+				&m_IMSI,
+				identity_type);
+			if (status != eap_status_ok)
+			{
+				// ERROR in handle_imsi_from_username().
+				// This will return error status of handle_imsi_from_username() call.
+			}
+			else
+			{
+				// OK handle_imsi_from_username().
+			}
+		}
+	}
+
+	EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+	return EAP_STATUS_RETURN(m_am_tools, status);
+}
+
+//--------------------------------------------------
+
+//
+EAP_FUNC_EXPORT eap_status_e eap_type_gsmsim_c::handle_imsi_from_username(
+	const u8_t next_eap_identifier,
+	const eap_am_network_id_c * const network_id,
+	const eap_variable_data_c * const username,
+	const eap_variable_data_c * const imsi, ///< The result is stored to imsi parameter.
+	const eap_type_gsmsim_identity_type received_identity_type)
+{
+	EAP_TRACE_BEGIN(m_am_tools, TRACE_FLAGS_DEFAULT);
+
+	EAP_UNREFERENCED_PARAMETER(username);
+	EAP_UNREFERENCED_PARAMETER(network_id);
+
+	EAP_ASSERT(received_identity_type == GSMSIM_IDENTITY_TYPE_IMSI_ID
+		|| received_identity_type == GSMSIM_IDENTITY_TYPE_PSEUDONYM_ID
+		|| received_identity_type == GSMSIM_IDENTITY_TYPE_RE_AUTH_ID
+		|| received_identity_type == GSMSIM_IDENTITY_TYPE_NONE);
+
+	if (m_state != eap_type_gsmsim_state_pending_pseudonym_decode_query)
+	{
+		// State is wrong. Cannot continue.
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_wrong_gsmsim_state);
+	}
+
+	eap_status_e status = eap_status_process_general_error;
+	bool pseudonym_decode_failed = true;
+
+	set_identity_type(received_identity_type);
+
+	if (imsi != 0
+		&& imsi->get_is_valid_data() == true)
+	{
+		pseudonym_decode_failed = false;
+		status = m_IMSI.set_copy_of_buffer(imsi);
+		if (status != eap_status_ok)
+		{
+			restore_saved_previous_state();
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+
+		if (received_identity_type == GSMSIM_IDENTITY_TYPE_NONE)
+		{
+			set_identity_type(GSMSIM_IDENTITY_TYPE_IMSI_ID);
+		}
+	}
+	else
+	{
+		m_IMSI.reset();
+	}
+
+	if (m_identity_type == GSMSIM_IDENTITY_TYPE_IMSI_ID)
+	{
+		m_authentication_type = GSMSIM_AUTHENTICATION_TYPE_FULL_AUTH;
+
+		EAP_TRACE_DEBUG(
+			m_am_tools, 
+			TRACE_FLAGS_DEFAULT|TRACE_TEST_VECTORS, 
+			(EAPL("Identity: IMSI\n")));
+	}
+	else if (m_identity_type == GSMSIM_IDENTITY_TYPE_PSEUDONYM_ID)
+	{
+		m_authentication_type = GSMSIM_AUTHENTICATION_TYPE_FULL_AUTH;
+
+		EAP_TRACE_DEBUG(
+			m_am_tools, 
+			TRACE_FLAGS_DEFAULT|TRACE_TEST_VECTORS, 
+			(EAPL("Identity: pseudonym\n")));
+	}
+	else if (m_identity_type == GSMSIM_IDENTITY_TYPE_RE_AUTH_ID)
+	{
+		m_authentication_type = GSMSIM_AUTHENTICATION_TYPE_REAUTHENTICATION;
+
+		EAP_TRACE_DEBUG(
+			m_am_tools, 
+			TRACE_FLAGS_DEFAULT|TRACE_TEST_VECTORS, 
+			(EAPL("Identity: re-authentication\n")));
+	}
+	else
+	{
+		m_authentication_type = GSMSIM_AUTHENTICATION_TYPE_NONE;
+
+		EAP_TRACE_DEBUG(
+			m_am_tools, 
+			TRACE_FLAGS_DEFAULT|TRACE_TEST_VECTORS, 
+			(EAPL("Identity: other\n")));
+	}
+
+	if ((m_identity_type == GSMSIM_IDENTITY_TYPE_IMSI_ID
+			&& (m_saved_previous_state == eap_type_gsmsim_state_waiting_for_identity_response
+				|| m_saved_previous_state == eap_type_gsmsim_state_waiting_for_start_response_with_at_permanent_identity
+				|| m_saved_previous_state == eap_type_gsmsim_state_waiting_for_start_response_with_at_full_auth_identity
+				|| m_saved_previous_state == eap_type_gsmsim_state_waiting_for_start_response_with_at_any_identity
+				|| m_saved_previous_state == eap_type_gsmsim_state_waiting_for_start_response))
+		|| (m_identity_type == GSMSIM_IDENTITY_TYPE_PSEUDONYM_ID
+			&& (m_saved_previous_state == eap_type_gsmsim_state_waiting_for_identity_response
+				|| m_saved_previous_state == eap_type_gsmsim_state_waiting_for_start_response_with_at_permanent_identity
+				|| m_saved_previous_state == eap_type_gsmsim_state_waiting_for_start_response_with_at_any_identity
+				|| m_saved_previous_state == eap_type_gsmsim_state_waiting_for_start_response))
+		|| m_identity_type == GSMSIM_IDENTITY_TYPE_NONE)
+	{
+
+		if (m_identity_type == GSMSIM_IDENTITY_TYPE_IMSI_ID)
+		{
+			set_start_response_includes_identity(gsmsim_payload_AT_PERMANENT_ID_REQ);
+		}
+		else if (m_identity_type == GSMSIM_IDENTITY_TYPE_PSEUDONYM_ID)
+		{
+			set_start_response_includes_identity(gsmsim_payload_AT_FULLAUTH_ID_REQ);
+		}
+		else if (m_identity_type == GSMSIM_IDENTITY_TYPE_NONE)
+		{
+			set_start_response_includes_identity(gsmsim_payload_AT_ANY_ID_REQ);
+			pseudonym_decode_failed = true;
+		}
+
+		status = send_start_request_message(
+			pseudonym_decode_failed,
+			next_eap_identifier);
+	}
+	else if (m_identity_type == GSMSIM_IDENTITY_TYPE_RE_AUTH_ID
+		&& (m_saved_previous_state == eap_type_gsmsim_state_waiting_for_start_response_with_at_any_identity
+			|| m_saved_previous_state == eap_type_gsmsim_state_waiting_for_identity_response
+			|| m_saved_previous_state == eap_type_gsmsim_state_waiting_for_start_response))
+	{
+		// Here we need to send EAP-Request/Re-authentication
+		status = send_reauthentication_request_message(
+			&m_NAI,
+			pseudonym_decode_failed,
+			next_eap_identifier);
+	}
+	else
+	{
+		EAP_TRACE_ERROR(
+			m_am_tools, 
+			TRACE_FLAGS_GSMSIM_ERROR, 
+			(EAPL("ERROR: eap_type_gsmsim_c::handle_imsi_from_username(): ")
+			 EAPL("EAP-Identity type 0x%02x is wrong in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+			m_identity_type,
+			m_saved_previous_state,
+			get_saved_previous_state_string()));
+
+		status = eap_status_illegal_eap_identity;
+	}
+
+	if (status != eap_status_ok)
+	{
+		restore_saved_previous_state();
+	}
+	else
+	{
+		m_last_eap_identifier = next_eap_identifier;
+	}
+
+	EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+	return EAP_STATUS_RETURN(m_am_tools, status);
+}
+
+//--------------------------------------------------
+
+//
+EAP_FUNC_EXPORT eap_status_e eap_type_gsmsim_c::complete_imsi_from_username(
+	const u8_t next_eap_identifier,
+	const eap_am_network_id_c * const network_id,
+	const eap_variable_data_c * const username,
+	const eap_variable_data_c * const imsi, ///< The result is stored to imsi parameter.
+	const eap_type_gsmsim_identity_type identity_type,
+	const eap_status_e completion_status,
+	const eap_type_gsmsim_complete_e completion_action)
+{
+	EAP_TRACE_BEGIN(m_am_tools, TRACE_FLAGS_DEFAULT);
+
+	EAP_TRACE_DEBUG(
+		m_am_tools, 
+		TRACE_FLAGS_DEFAULT|TRACE_TEST_VECTORS, 
+		(EAPL("eap_type_gsmsim_c::complete_imsi_from_username(): identity_type %d=%s, requested identity payload is %d=%s\n"),
+		 identity_type,
+		 get_identity_string(identity_type),
+		 m_start_response_includes_identity,
+		 gsmsim_payload_AT_header_c::get_payload_AT_string(m_start_response_includes_identity)));
+
+	EAP_UNREFERENCED_PARAMETER(username);
+	EAP_UNREFERENCED_PARAMETER(network_id);
+
+	if (completion_status != eap_status_ok)
+	{
+		set_state(eap_type_gsmsim_state_failure);
+
+		// The completion_status error value is more important
+		// than return value of set_session_timeout().
+		get_type_partner()->set_session_timeout(0ul);
+
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, completion_status);
+	}
+
+	eap_status_e status = eap_status_not_supported;
+
+	if (completion_action == eap_type_gsmsim_complete_handle_imsi_from_username)
+	{
+		status = handle_imsi_from_username(
+			next_eap_identifier,
+			network_id,
+			username,
+			imsi, ///< The result is stored to imsi parameter.
+			identity_type);
+
+		status = eap_status_completed_request;
+	}
+	else if (completion_action == eap_type_gsmsim_complete_handle_start_response_message_completion)
+	{
+		// NOTE the identity_payload_was_included parameter is
+		// true in this completion.
+		status = handle_start_response_message_completion(
+			next_eap_identifier,
+			completion_status,
+			identity_type,
+			true);
+
+		status = eap_status_completed_request;
+	}
+	else
+	{
+		// Unknown completion.
+		EAP_TRACE_ERROR(
+			m_am_tools, 
+			TRACE_FLAGS_GSMSIM_ERROR, 
+			(EAPL("ERROR: eap_type_gsmsim_c::complete_imsi_from_username(): ")
+			 EAPL("Unknown eap_type_gsmsim_complete_e %d in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+			completion_action,
+			m_saved_previous_state,
+			get_saved_previous_state_string()));
+	}
+
+	EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+	return EAP_STATUS_RETURN(m_am_tools, status);
+}
+
+//--------------------------------------------------
+
+//
+EAP_FUNC_EXPORT eap_status_e eap_type_gsmsim_c::handle_start_response_message_completion(
+	const u8_t next_eap_identifier,
+	const eap_status_e identity_status,
+	eap_type_gsmsim_identity_type received_identity_type,
+	const bool identity_payload_was_included)
+{
+	EAP_TRACE_DEBUG(
+		m_am_tools, 
+		TRACE_FLAGS_DEFAULT|TRACE_TEST_VECTORS, 
+		(EAPL("eap_type_gsmsim_c::handle_start_response_message_completion(): received_identity_type %d=%s, requested identity payload is %d=%s\n"),
+		 received_identity_type,
+		 get_identity_string(received_identity_type),
+		 m_start_response_includes_identity,
+		 gsmsim_payload_AT_header_c::get_payload_AT_string(m_start_response_includes_identity)));
+
+	if (m_state == eap_type_gsmsim_state_none)
+	{
+		// Authentication is terminated or state is wrong. Cannot continue.
+
+		// The eap_status_handler_does_not_exists_error error value is more important
+		// than return value of set_session_timeout().
+		get_type_partner()->set_session_timeout(0ul);
+
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_handler_does_not_exists_error);
+	}
+
+	if (identity_payload_was_included == true)
+	{
+		if (identity_status != eap_status_ok
+			|| received_identity_type == GSMSIM_IDENTITY_TYPE_NONE)
+		{
+			// We did not get valid identity.
+			set_identity_type(GSMSIM_IDENTITY_TYPE_NONE);
+			received_identity_type = GSMSIM_IDENTITY_TYPE_NONE;
+
+			if (m_start_response_includes_identity == gsmsim_payload_AT_ANY_ID_REQ)
+			{
+				set_start_response_includes_identity(gsmsim_payload_AT_FULLAUTH_ID_REQ);
+			}
+			else // if (m_start_response_includes_identity == gsmsim_payload_AT_FULLAUTH_ID_REQ)
+			{
+				set_start_response_includes_identity(gsmsim_payload_AT_PERMANENT_ID_REQ);
+			}
+		}
+		else
+		{
+			set_identity_type(received_identity_type);
+		}
+
+		if (m_identity_type == GSMSIM_IDENTITY_TYPE_IMSI_ID)
+		{
+			m_authentication_type = GSMSIM_AUTHENTICATION_TYPE_FULL_AUTH;
+
+			EAP_TRACE_DEBUG(
+				m_am_tools, 
+				TRACE_FLAGS_DEFAULT|TRACE_TEST_VECTORS, 
+				(EAPL("Identity: IMSI\n")));
+		}
+		else if (m_identity_type == GSMSIM_IDENTITY_TYPE_PSEUDONYM_ID)
+		{
+			m_authentication_type = GSMSIM_AUTHENTICATION_TYPE_FULL_AUTH;
+
+			EAP_TRACE_DEBUG(
+				m_am_tools, 
+				TRACE_FLAGS_DEFAULT|TRACE_TEST_VECTORS, 
+				(EAPL("Identity: pseudonym\n")));
+		}
+		else if (m_identity_type == GSMSIM_IDENTITY_TYPE_RE_AUTH_ID)
+		{
+			m_authentication_type = GSMSIM_AUTHENTICATION_TYPE_REAUTHENTICATION;
+
+			EAP_TRACE_DEBUG(
+				m_am_tools, 
+				TRACE_FLAGS_DEFAULT|TRACE_TEST_VECTORS, 
+				(EAPL("Identity: re-authentication\n")));
+
+			// Here nonce_mt and SELECTED_VERSION MUST NOT be included.
+			// Note nonce_mt is copied earlier to handler.
+			if (m_nonce_mt.get_is_valid_data() == true
+				|| m_gsmsim_selected_version != GSMSIM_ILLEGAL_VERSION)
+			{
+				// Not correct GSMSIM-payloads are included.
+				EAP_TRACE_ERROR(
+					m_am_tools, 
+					TRACE_FLAGS_GSMSIM_ERROR, 
+					(EAPL("ERROR: eap_type_gsmsim_c::handle_start_response_message_completion(4): ")
+					 EAPL("Not correct GSMSIM-payloads are included in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+					 m_state,
+					get_state_string()));
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+			}
+		}
+		else
+		{
+			m_authentication_type = GSMSIM_AUTHENTICATION_TYPE_NONE;
+
+			EAP_TRACE_DEBUG(
+				m_am_tools, 
+				TRACE_FLAGS_DEFAULT|TRACE_TEST_VECTORS, 
+				(EAPL("Identity: other\n")));
+		}
+	}
+	else
+	{
+		// No AT_IDENTITY payload.
+		// We may have identity already.
+		if (m_identity.get_is_valid_data() == true
+			&& m_authentication_type != GSMSIM_AUTHENTICATION_TYPE_NONE
+			&& m_identity_type != GSMSIM_IDENTITY_TYPE_NONE)
+		{
+			// OK identity is known.
+			EAP_TRACE_DEBUG(
+				m_am_tools, 
+				TRACE_FLAGS_DEFAULT|TRACE_TEST_VECTORS, 
+				(EAPL("eap_type_gsmsim_c::handle_start_response_message_completion(): Known m_identity_type %d=%s, requested identity payload is %d=%s\n"),
+				 m_identity_type,
+				 get_identity_string(m_identity_type),
+				 m_start_response_includes_identity,
+				 gsmsim_payload_AT_header_c::get_payload_AT_string(m_start_response_includes_identity)));
+		}
+		else
+		{
+			// ERROR no accepted identity.
+			EAP_TRACE_ERROR(
+				m_am_tools, 
+				TRACE_FLAGS_GSMSIM_ERROR, 
+				(EAPL("ERROR: eap_type_gsmsim_c::handle_start_response_message_completion(5): ")
+				 EAPL("No correct GSMSIM-identity were received in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+				 m_state,
+				get_state_string()));
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+		}
+	}
+
+
+
+	save_current_state();
+
+	u8_t local_eap_identifier(next_eap_identifier);
+
+	if (m_identity_type == GSMSIM_IDENTITY_TYPE_NONE)
+	{
+		// This will send EAP-Request/SIM/Start with identity request.
+		eap_status_e local_status = send_start_request_message(
+			true,
+			local_eap_identifier);
+		if (local_status != eap_status_ok)
+		{
+			restore_saved_previous_state();
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, local_status);
+		}
+		m_last_eap_identifier = local_eap_identifier;
+
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, local_status);
+	}
+	else if (m_identity_type == GSMSIM_IDENTITY_TYPE_IMSI_ID
+		|| m_identity_type == GSMSIM_IDENTITY_TYPE_PSEUDONYM_ID
+		|| (m_identity_type == GSMSIM_IDENTITY_TYPE_RE_AUTH_ID
+			&& m_authentication_type == GSMSIM_AUTHENTICATION_TYPE_FULL_AUTH))
+	{
+		eap_type_gsmsim_identity_type local_identity_type = m_identity_type;
+
+		eap_status_e local_status = query_SIM_triplets(&local_identity_type);
+		if (local_status == eap_status_pending_request)
+		{
+			// Request will be completed later with complete_SIM_triplets() function.
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, eap_status_ok);
+		}
+		else if (local_status == eap_status_completed_request)
+		{
+			// Request was already completed with complete_SIM_triplets() function.
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, eap_status_ok);
+		}
+		else if (local_status != eap_status_ok)
+		{
+			// This is an error case.
+			restore_saved_previous_state();
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, local_status);
+		}
+		else //if (local_status == eap_status_ok)
+		{
+			// The query_SIM_triplets() function call is synchronous.
+			// We must call send_challenge_request_message().
+		}
+
+		local_status = send_challenge_request_message(
+			local_eap_identifier);
+		if (local_status != eap_status_ok)
+		{
+			restore_saved_previous_state();
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, local_status);
+		}
+
+		m_last_eap_identifier = local_eap_identifier;
+		set_state(eap_type_gsmsim_state_waiting_for_challenge_response);
+
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, local_status);
+	}
+	else if (m_identity_type == GSMSIM_IDENTITY_TYPE_RE_AUTH_ID
+			&& m_authentication_type == GSMSIM_AUTHENTICATION_TYPE_REAUTHENTICATION)
+	{
+		// Here we need to send EAP-Request/Re-authentication
+		eap_status_e local_status = send_reauthentication_request_message(
+			&m_NAI,
+			false,
+			local_eap_identifier);
+
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, local_status);
+	}
+	else
+	{
+		// Unnown identity type, do nothing.
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_eap_identity);
+	}
+
+}
+
+//--------------------------------------------------
+
+//
+EAP_FUNC_EXPORT eap_status_e eap_type_gsmsim_c::handle_start_response_message(
+	gsmsim_header_c * const received_gsmsim,
+	const u32_t gsmsim_packet_length,
+	gsmsim_payloads_c * const p_gsmsim_payloads)
+{
+	eap_status_e status = eap_status_process_general_error;
+
+	EAP_TRACE_DEBUG(
+		m_am_tools, 
+		TRACE_FLAGS_DEFAULT|TRACE_TEST_VECTORS, 
+		(EAPL("eap_type_gsmsim_c::handle_start_response_message(): m_identity_type %d=%s, requested identity payload is %d=%s\n"),
+		 m_identity_type,
+		 get_identity_string(m_identity_type),
+		 m_start_response_includes_identity,
+		 gsmsim_payload_AT_header_c::get_payload_AT_string(m_start_response_includes_identity)));
+
+	if (gsmsim_packet_length < received_gsmsim->get_length())
+	{
+		EAP_TRACE_ERROR(
+			m_am_tools, 
+			TRACE_FLAGS_GSMSIM_ERROR, 
+			(EAPL("ERROR: eap_type_gsmsim_c::handle_start_response_message(): ")
+			 EAPL("gsmsim_packet_length < received_gsmsim->get_length().\n")));
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_process_illegal_packet_error);
+	}
+
+#if defined(USE_EAP_GSMSIM_VERIFY_STATES)
+	const eap_type_gsmsim_state_variable_e gsmsim_start_response_states_1[] =
+	{
+		eap_type_gsmsim_state_waiting_for_start_response,
+		eap_type_gsmsim_state_waiting_for_start_response_with_at_any_identity,
+		eap_type_gsmsim_state_waiting_for_start_response_with_at_full_auth_identity,
+		eap_type_gsmsim_state_waiting_for_start_response_with_at_permanent_identity,
+		eap_type_gsmsim_state_waiting_for_challenge_response,
+	};
+
+	const eap_type_gsmsim_state_variable_e gsmsim_start_response_states_2[] =
+	{
+		eap_type_gsmsim_state_waiting_for_start_response,
+		eap_type_gsmsim_state_waiting_for_start_response_with_at_any_identity,
+		eap_type_gsmsim_state_waiting_for_start_response_with_at_full_auth_identity,
+		eap_type_gsmsim_state_waiting_for_start_response_with_at_permanent_identity,
+	};
+
+	if (verify_states(gsmsim_start_response_states_1, GSMSIM_STATE_COUNT(gsmsim_start_response_states_1)) == true)
+#else
+	if (m_state == eap_type_gsmsim_state_waiting_for_start_response
+		|| m_state == eap_type_gsmsim_state_waiting_for_start_response_with_at_any_identity
+		|| m_state == eap_type_gsmsim_state_waiting_for_start_response_with_at_full_auth_identity
+		|| m_state == eap_type_gsmsim_state_waiting_for_start_response_with_at_permanent_identity
+		|| m_state == eap_type_gsmsim_state_waiting_for_challenge_response
+		)
+#endif //#if defined(USE_EAP_GSMSIM_VERIFY_STATES)
+	{
+#if defined(USE_EAP_GSMSIM_VERIFY_STATES)
+		if (verify_states(gsmsim_start_response_states_2, GSMSIM_STATE_COUNT(gsmsim_start_response_states_2)) == true)
+#else
+		if (m_state == eap_type_gsmsim_state_waiting_for_start_response
+			|| m_state == eap_type_gsmsim_state_waiting_for_start_response_with_at_any_identity
+			|| m_state == eap_type_gsmsim_state_waiting_for_start_response_with_at_full_auth_identity
+			|| m_state == eap_type_gsmsim_state_waiting_for_start_response_with_at_permanent_identity
+			)
+#endif //#if defined(USE_EAP_GSMSIM_VERIFY_STATES)
+		{
+			if (received_gsmsim->get_identifier() != m_last_eap_identifier)
+			{
+				// Wrong EAP-Identifier in this state.
+				EAP_TRACE_ERROR(
+					m_am_tools, 
+					TRACE_FLAGS_GSMSIM_ERROR, 
+					(EAPL("ERROR: eap_type_gsmsim_c::handle_start_response_message(): ")
+					 EAPL("EAP-Identifier 0x%02x is wrong (0x%02x is correct) ")
+					 EAPL("in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+					 received_gsmsim->get_identifier(),
+					 m_last_eap_identifier, 
+					 m_state,
+					 get_state_string()));
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_eap_identity);
+			}
+		}
+		else // if (m_state == eap_type_gsmsim_state_waiting_for_challenge_response)
+		{
+			// This might be retransmission response.
+			if (received_gsmsim->get_identifier() != m_last_eap_identifier-1u)
+			{
+				// Wrong EAP-Identifier in this state.
+				EAP_TRACE_ERROR(
+					m_am_tools, 
+					TRACE_FLAGS_GSMSIM_ERROR, 
+					(EAPL("ERROR: eap_type_gsmsim_c::handle_start_response_message(): ")
+					 EAPL("EAP-Identifier 0x%02x is wrong (0x%02x is correct) ")
+					 EAPL("in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+					 received_gsmsim->get_identifier(),
+					 m_last_eap_identifier-1u, 
+					 m_state,
+					 get_state_string()));
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_eap_identity);
+			}
+		}
+
+
+		// Checks the payloads existence.
+		if (p_gsmsim_payloads->check_payloads(
+				gsmsim_payloads_c::eap_gsmsim_payload_status_optional,     // nonce_mt, not included in re-authentication
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // nonce_s
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // MAC
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // ENCR_DATA
+				gsmsim_payloads_c::eap_gsmsim_payload_status_optional,    // IDENTITY
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // padding
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // n_RANDs
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // PERMANENT_ID_REQ
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // FULLAUTH_ID_REQ
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // ANY_ID_REQ
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // IV
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // NEXT_PSEUDONYM
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // NEXT_REAUTH_ID
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // NOTIFICATION
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // VERSION_LIST
+				gsmsim_payloads_c::eap_gsmsim_payload_status_optional,     // SELECTED_VERSION, not included in re-authentication
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // COUNTER
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // COUNTER_TOO_SMALL
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be,  // CLIENT_ERROR_CODE
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be  // RESULT_IND
+				) == true
+			)
+		{
+			if (m_state == eap_type_gsmsim_state_waiting_for_start_response_with_at_permanent_identity)
+			{
+				if (p_gsmsim_payloads->get_IDENTITY_payload()->get_payload_included() == true)
+				{
+					// OK, NAI identity is included.
+					// Identity must be IMSI. query_SIM_triplets() must decode identity.
+
+					set_start_response_includes_identity(gsmsim_payload_AT_PERMANENT_ID_REQ);
+				}
+				else
+				{
+					// AT_IDENTITY is missing.
+					EAP_TRACE_ERROR(
+						m_am_tools, 
+						TRACE_FLAGS_GSMSIM_ERROR, 
+						(EAPL("ERROR: eap_type_gsmsim_c::handle_start_response_message(0x%08x), ")
+						 EAPL("AT_IDENTITY is missing.\n"),
+						 this));
+					EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+					return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+				}
+			}
+			else if (m_state == eap_type_gsmsim_state_waiting_for_start_response_with_at_full_auth_identity)
+			{
+				if (p_gsmsim_payloads->get_IDENTITY_payload()->get_payload_included() == true)
+				{
+					// OK, NAI identity is included.
+					// Identity must be IMSI or pseudonym identity. query_SIM_triplets() must decode identity.
+
+					set_start_response_includes_identity(gsmsim_payload_AT_FULLAUTH_ID_REQ);
+				}
+				else
+				{
+					// AT_IDENTITY is missing.
+					EAP_TRACE_ERROR(
+						m_am_tools, 
+						TRACE_FLAGS_GSMSIM_ERROR, 
+						(EAPL("ERROR: eap_type_gsmsim_c::handle_start_response_message(0x%08x), ")
+						 EAPL("AT_IDENTITY is missing.\n"),
+						 this));
+					EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+					return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+				}
+			}			
+			else if (m_state == eap_type_gsmsim_state_waiting_for_start_response_with_at_any_identity)
+			{
+				if (p_gsmsim_payloads->get_IDENTITY_payload()->get_payload_included() == true)
+				{
+					// OK, NAI identity is included.
+					// Identity must be IMSI, pseudonym or re-authentication identity. query_SIM_triplets() must decode identity.
+
+					set_start_response_includes_identity(gsmsim_payload_AT_ANY_ID_REQ);
+				}
+				else
+				{
+					// AT_IDENTITY is missing.
+					EAP_TRACE_ERROR(
+						m_am_tools, 
+						TRACE_FLAGS_GSMSIM_ERROR, 
+						(EAPL("ERROR: eap_type_gsmsim_c::handle_start_response_message(0x%08x), ")
+						 EAPL("AT_IDENTITY is missing.\n"),
+						 this));
+					EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+					return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+				}
+			}
+			else if (m_state == eap_type_gsmsim_state_waiting_for_challenge_response)
+			{
+				// This is re-transmission.
+				if (p_gsmsim_payloads->get_IDENTITY_payload()->get_payload_included() == true)
+				{
+					if (m_start_response_includes_identity == gsmsim_payload_AT_PERMANENT_ID_REQ
+						|| m_start_response_includes_identity == gsmsim_payload_AT_FULLAUTH_ID_REQ
+						|| m_start_response_includes_identity == gsmsim_payload_AT_ANY_ID_REQ)
+					{
+						// OK, NAI identity is included.
+					}
+					else
+					{
+						// Illegal IDENTITY is included.
+						EAP_TRACE_ERROR(
+							m_am_tools, 
+							TRACE_FLAGS_GSMSIM_ERROR, 
+							(EAPL("ERROR: eap_type_gsmsim_c::handle_start_response_message(0x%08x), ")
+							 EAPL("illegal AT_IDENTITY included.\n"),
+							 this));
+						EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+						return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+					}
+				}
+			}
+			else
+			{
+				if (p_gsmsim_payloads->get_IDENTITY_payload()->get_payload_included() == true)
+				{
+					// Illegal IDENTITY is included.
+					EAP_TRACE_ERROR(
+						m_am_tools, 
+						TRACE_FLAGS_GSMSIM_ERROR, 
+						(EAPL("ERROR: eap_type_gsmsim_c::handle_start_response_message(0x%08x), ")
+						 EAPL("illegal AT_IDENTITY included.\n"),
+						 this));
+					EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+					return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+				}
+			}
+
+
+			if (p_gsmsim_payloads->get_NONCE_MT()->get_payload_included() == true)
+			{
+				// NOTE on re-authentication Start-message does not include NONCE_MT.
+				eap_status_e local_status = m_nonce_mt.set_copy_of_buffer(
+					p_gsmsim_payloads->get_NONCE_MT()->get_payload_buffer());
+				if (local_status != eap_status_ok)
+				{
+					EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+					return EAP_STATUS_RETURN(m_am_tools, local_status);
+				}
+			}
+
+
+			if (p_gsmsim_payloads->get_SELECTED_VERSION()->get_payload_included() == true)
+			{
+				// NOTE on re-authentication Start-message does not include SELECTED_VERSION.
+				const eap_gsmsim_version selected_version
+					= static_cast<eap_gsmsim_version>(p_gsmsim_payloads
+					->get_SELECTED_VERSION()->get_original_header()->get_reserved());
+
+				u16_t supported_versions[GSMSIM_LAST_VERSION];
+
+				for (u32_t ind = 0u; ind < GSMSIM_LAST_VERSION; ind++)
+				{
+					supported_versions[ind] = eap_htons(static_cast<u16_t>(m_supported_versions[ind]));
+				}
+
+				{
+					eap_status_e local_status = save_version(
+						supported_versions,
+						GSMSIM_LAST_VERSION,
+						selected_version);
+					if (local_status != eap_status_ok)
+					{
+						EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+						return EAP_STATUS_RETURN(m_am_tools, local_status);
+					}
+				}
+
+				if (p_gsmsim_payloads->get_includes_unknown_attribute() != gsmsim_payload_NONE
+					&& selected_version == GSMSIM_VERSION_1)
+				{
+					// EAP-SIM version 1 must NOT include unknown attributes.
+					EAP_TRACE_ERROR(
+						m_am_tools, 
+						TRACE_FLAGS_GSMSIM_ERROR, 
+						(EAPL("ERROR: eap_type_gsmsim_c::handle_start_response_message(0x%08x), illegal payload %d=0x%04x.\n"),
+						this,
+						p_gsmsim_payloads->get_includes_unknown_attribute(),
+						p_gsmsim_payloads->get_includes_unknown_attribute()));
+					EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+					return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+				}
+			}
+
+
+			eap_type_gsmsim_identity_type identity_type = GSMSIM_IDENTITY_TYPE_NONE;
+			bool identity_payload_was_included = false;
+			const u8_t next_eap_identifier = static_cast<u8_t>(received_gsmsim->get_identifier()+1u);
+
+			if (p_gsmsim_payloads->get_IDENTITY_payload()->get_payload_included() == true)
+			{
+				status = parse_identity(
+					p_gsmsim_payloads->get_IDENTITY_payload()->get_data(p_gsmsim_payloads->get_IDENTITY_payload()->get_data_length()),
+					p_gsmsim_payloads->get_IDENTITY_payload()->get_data_length());
+				if (status != eap_status_ok)
+				{
+					EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+					return EAP_STATUS_RETURN(m_am_tools, status);
+				}
+
+				identity_payload_was_included = true;
+
+				// We must ask AM module whether the identity is IMSI, pseudonym or re-authentication identity.
+				// If we have re-authentication identity we must send re-authentication query.
+
+				if (randomly_refuse_eap_identity() == false)
+				{
+					status = m_am_type_gsmsim->query_imsi_from_username(
+						false,
+						next_eap_identifier,
+						&m_send_network_id,
+						&m_identity,
+						&m_IMSI,
+						&identity_type,
+						eap_type_gsmsim_complete_handle_start_response_message_completion);
+					if (status == eap_status_pending_request)
+					{
+						// This is pending query, that will be completed by complete_imsi_from_username() call.
+						EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+						return EAP_STATUS_RETURN(m_am_tools, eap_status_pending_request);
+					}
+					else if (status == eap_status_completed_request)
+					{
+						// This is already completed by complete_imsi_from_username() call.
+						EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+						return EAP_STATUS_RETURN(m_am_tools, eap_status_ok);
+					}
+					else if (status != eap_status_ok)
+					{
+						// ERROR in query_imsi_from_username().
+						// This will return error status of query_imsi_from_username() call.
+
+						// Let handle_start_response_message_completion() handle error cases.
+					}
+					else // status == eap_status_ok
+					{
+						// The query_imsi_from_username() function call was synchronous.
+						// We must call handle_start_response_message_completion().
+					}
+				}
+				else
+				{
+					status = eap_status_illegal_eap_identity;
+				}
+			}
+
+
+			status = handle_start_response_message_completion(
+				next_eap_identifier,
+				status,
+				identity_type,
+				identity_payload_was_included);
+
+
+		}
+		else
+		{
+			// Not correct GSMSIM-payloads are included.
+			EAP_TRACE_ERROR(
+				m_am_tools, 
+				TRACE_FLAGS_GSMSIM_ERROR, 
+				(EAPL("ERROR: eap_type_gsmsim_c::handle_start_response_message(4): ")
+				 EAPL("Not correct GSMSIM-payloads are included in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+				 m_state,
+				 get_state_string()));
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+		}
+	}
+	else if (m_state == eap_type_gsmsim_state_pending_triplet_query)
+	{
+		// This is retransmission of EAP-Response/SIM/Start.
+		// Triplet query is already initialized.
+		// We will drop this message quietly.
+		EAP_TRACE_DEBUG(
+			m_am_tools, 
+			TRACE_FLAGS_DEFAULT, 
+			(EAPL("WARNING: eap_type_gsmsim_c::handle_start_response_message(5): ")
+			 EAPL("Retransmission of EAP-Response/SIM/Start in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+			 m_state,
+			 get_state_string()));
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_drop_packet_quietly);
+	}
+	else
+	{
+		// Wrong message in this state.
+		EAP_TRACE_ERROR(
+			m_am_tools, 
+			TRACE_FLAGS_GSMSIM_ERROR, 
+			(EAPL("ERROR: eap_type_gsmsim_c::handle_start_response_message(): ")
+			 EAPL("Wrong message %d=%s in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+			 received_gsmsim->get_subtype(),
+			 received_gsmsim->get_subtype_string(),
+			 m_state,
+			 get_state_string()));
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+	}
+
+	EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+	return EAP_STATUS_RETURN(m_am_tools, status);
+}
+
+//--------------------------------------------------
+
+//
+EAP_FUNC_EXPORT eap_status_e eap_type_gsmsim_c::handle_notification_response_message_reauthentication(
+	const eap_am_network_id_c * const receive_network_id,
+	gsmsim_header_c * const received_gsmsim,
+	const u32_t /*gsmsim_packet_length*/,
+	gsmsim_payloads_c * const p_gsmsim_payloads)
+{
+	eap_status_e status = eap_status_process_general_error;
+
+	EAP_TRACE_DEBUG(
+		m_am_tools, 
+		TRACE_FLAGS_DEFAULT, 
+		(EAPL("send: GSMSIM-type %10s, %s, state %2d=%s\n"),
+		 EAPL("handle_notification_response_message_reauthentication"),
+		 (m_is_client) ? EAPL("client") : EAPL("server"),
+		 m_state,
+		 get_state_string()
+		 ));
+
+	// The second most significant bit of the notification code is called
+	// the Phase bit (P bit). It specifies at which phase of the EAP-SIM
+	// exchange the notification can be used.
+	if (get_gsmsim_notification_code_P_bit(m_gsmsim_notification_code) == false)
+	{
+		// If the P bit is set to zero,
+		// the notification can only be used after a successful EAP/SIM/
+		// Challenge round in full authentication or a successful EAP/SIM/
+		// Re-authentication round in reautentication. A re-authentication round
+		// is considered successful only if the peer has successfully verified
+		// AT_MAC and AT_COUNTER attributes, and does not include the
+		// AT_COUNTER_TOO_SMALL attribute in EAP-Response/SIM/Re-authentication.
+
+		// The AT_MAC attribute MUST be included if the P bit of the notification
+		// code in AT_NOTIFICATION is set to zero, and MUST NOT be included in
+		// cases when the P bit is set to one. The P bit is discussed in Section
+		// 4.4.
+
+		// Checks the payloads existence.
+		if (p_gsmsim_payloads->check_payloads(
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // nonce_mt
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // nonce_s
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_be,     // MAC
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_be,     // ENCR_DATA
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // IDENTITY
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // padding
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // n_RANDs
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // PERMANENT_ID_REQ
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // FULLAUTH_ID_REQ
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // ANY_ID_REQ
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_be,     // IV
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // NEXT_PSEUDONYM
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // NEXT_REAUTH_ID
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // NOTIFICATION
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // VERSION_LIST
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // SELECTED_VERSION
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // COUNTER
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // COUNTER_TOO_SMALL
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be,  // CLIENT_ERROR_CODE
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be  // RESULT_IND
+				) == true
+			)
+		{
+			eap_variable_data_c orig_XKEY(m_am_tools);
+			eap_variable_data_c orig_K_aut(m_am_tools);
+			eap_variable_data_c orig_K_encr(m_am_tools);
+			u32_t reauth_counter = 0u;
+
+			// In order to use re-authentication, the client and the server need to
+			// store the following values: original XKEY, K_aut, K_encr, latest
+			// counter value and the next re-authentication identity.
+			status = m_am_type_gsmsim->query_reauth_parameters(
+				&orig_XKEY,
+				&orig_K_aut,
+				&orig_K_encr,
+				&reauth_counter);
+			if (status != eap_status_ok)
+			{
+				restore_saved_previous_state();
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, status);
+			}
+
+			EAP_TRACE_DEBUG(
+				m_am_tools,
+				TRACE_FLAGS_DEFAULT,
+				(EAPL("eap_type_gsmsim_c::handle_notification_response_message_reauthentication(): %s, m_saved_reauth_counter %d.\n"),
+				 (m_is_client == true ? "client": "server"),
+				 reauth_counter));
+
+			status = check_message_authentication_code(
+				&orig_K_aut,
+				p_gsmsim_payloads,
+				received_gsmsim,
+				received_gsmsim->get_length());
+			if (status != eap_status_ok)
+			{
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, status);
+			}
+
+			bool authentication_ok = true;
+
+			// Decrypt and parse encrypted payload.
+			{
+				gsmsim_payloads_c * const l_gsmsim_payloads = new gsmsim_payloads_c(m_am_tools);
+				eap_automatic_variable_c<gsmsim_payloads_c> l_gsmsim_payloads_automatic(m_am_tools, l_gsmsim_payloads);
+
+				if (l_gsmsim_payloads == 0
+					|| l_gsmsim_payloads->get_is_valid() == false)
+				{
+					EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+					return EAP_STATUS_RETURN(m_am_tools, eap_status_allocation_error);
+				}
+
+				status = decrypt_DATA_payload(
+					p_gsmsim_payloads,
+					&orig_K_encr);
+				if (status != eap_status_ok)
+				{
+					restore_saved_previous_state();
+					EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+					return EAP_STATUS_RETURN(m_am_tools, status);
+				}
+
+				u32_t state_payload_buffer_length = p_gsmsim_payloads->get_ENCR_DATA()->get_data_length();
+				const gsmsim_payload_AT_header_c gp_data_payload(
+					m_am_tools,
+					p_gsmsim_payloads->get_ENCR_DATA()->get_data(state_payload_buffer_length),
+					state_payload_buffer_length);
+
+				status = parse_gsmsim_payload(
+					&gp_data_payload,
+					&state_payload_buffer_length,
+					l_gsmsim_payloads,
+					received_gsmsim->get_subtype());
+				if (status != eap_status_ok)
+				{
+					restore_saved_previous_state();
+					EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+					return EAP_STATUS_RETURN(m_am_tools, status);
+				}
+
+
+				if (l_gsmsim_payloads->get_COUNTER()->get_payload_included() == false)
+				{
+					restore_saved_previous_state();
+					EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+					return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_payload);
+				}
+
+				u32_t counter = l_gsmsim_payloads->get_COUNTER()->get_original_header()->get_reserved();
+
+				if (counter == reauth_counter)
+				{
+					EAP_TRACE_DEBUG(
+						m_am_tools, 
+						TRACE_FLAGS_DEFAULT, 
+						(EAPL("eap_type_gsmsim_c::handle_notification_response_message_reauthentication(): ")
+						EAPL("reauth counter %d OK, %d=%s.\n"),
+						reauth_counter,
+						m_state,
+						get_state_string()));
+				}
+				else
+				{
+					EAP_TRACE_ERROR(
+						m_am_tools, 
+						TRACE_FLAGS_GSMSIM_ERROR, 
+						(EAPL("ERROR: eap_type_gsmsim_c::handle_notification_response_message_reauthentication(): ")
+						EAPL("reauth counter %d wrong, should be %d, %d=%s.\n"),
+						counter,
+						reauth_counter,
+						m_state,
+						get_state_string()));
+
+					authentication_ok = false;
+				}
+			}
+
+			// The most significant bit is called the Failure bit (F bit).
+			// The F bit specifies whether the notification implies failure.
+			if (authentication_ok == false
+				|| get_gsmsim_notification_code_F_bit(m_gsmsim_notification_code) == false)
+			{
+				// The code values with the F bit set to zero (code values 0...32767)
+				// are used on unsuccessful cases.
+				// The receipt of a notification code from this range implies failed EAP
+				// exchange, so the peer can use the notification as a failure indication.
+
+				m_last_eap_identifier = static_cast<u8_t>(m_last_eap_identifier+1u);
+				set_state(eap_type_gsmsim_state_failure);
+
+				// This will terminate session immediately.
+				get_type_partner()->set_session_timeout(0UL);
+
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, eap_status_ok);
+			}
+			else //if (get_gsmsim_notification_code_F_bit(m_gsmsim_notification_code) == true)
+			{
+				// The receipt of a notification code with the F bit set to one (values
+				// 32768...65536) does not imply failure. Notification code 32768 has
+				// been reserved as a general notification code to indicate successful
+				// authentication.
+				if (m_gsmsim_notification_code == eap_gsmsim_notification_F_set_no_P_user_authenticated)
+				{
+					// In order to use re-authentication, the client and the server need to
+					// update re-authentication counter value.
+					status = m_am_type_gsmsim->increase_reauth_counter();
+					if (status != eap_status_ok)
+					{
+						EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+						return EAP_STATUS_RETURN(m_am_tools, status);
+					}
+
+					status = finish_successful_authentication(
+						receive_network_id);
+
+					EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+					return EAP_STATUS_RETURN(m_am_tools, status);
+				}
+				else
+				{
+					EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+					return EAP_STATUS_RETURN(m_am_tools, eap_status_process_general_error);
+				}
+			}
+		}
+		else
+		{
+			// Not correct GSMSIM-payloads are included.
+			EAP_TRACE_ERROR(
+				m_am_tools, 
+				TRACE_FLAGS_GSMSIM_ERROR, 
+				(EAPL("ERROR: eap_type_gsmsim_c::handle_notification_response_message_reauthentication(): ")
+				 EAPL("Not correct GSMSIM-payloads are included ")
+				 EAPL("in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+				 m_state,
+				 get_state_string()));
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+		}
+	}
+	else //if (get_gsmsim_notification_code_P_bit(m_gsmsim_notification_code) == true)
+	{
+		// Checks the payloads existence.
+		if (p_gsmsim_payloads->check_payloads(
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // nonce_mt
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // nonce_s
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // MAC
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // ENCR_DATA
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // IDENTITY
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // padding
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // n_RANDs
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // PERMANENT_ID_REQ
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // FULLAUTH_ID_REQ
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // ANY_ID_REQ
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // IV
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // NEXT_PSEUDONYM
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // NEXT_REAUTH_ID
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // NOTIFICATION
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // VERSION_LIST
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // SELECTED_VERSION
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // COUNTER
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // COUNTER_TOO_SMALL
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be,  // CLIENT_ERROR_CODE
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be  // RESULT_IND
+				) == true
+			)
+		{
+			// If the P bit is set to one, the notification can only by used before
+			// the EAP/SIM/Challenge round in full authentication, or before the
+			// EAP/SIM/Re-authentication round in reauthentication.
+
+			// The most significant bit is called the Failure bit (F bit).
+			// The F bit specifies whether the notification implies failure.
+			if (get_gsmsim_notification_code_F_bit(m_gsmsim_notification_code) == false)
+			{
+				// The code values with the F bit set to zero (code values 0...32767)
+				// are used on unsuccessful cases.
+				// The receipt of a notification code from this range implies failed EAP
+				// exchange, so the peer can use the notification as a failure indication.
+			}
+			else //if (get_gsmsim_notification_code_F_bit(m_gsmsim_notification_code) == true)
+			{
+				// The receipt of a notification code with the F bit set to one (values
+				// 32768...65536) does not imply failure. Notification code 32768 has
+				// been reserved as a general notification code to indicate successful
+				// authentication.
+			}
+
+			status = initialize_error_message(
+				eap_status_process_general_error);
+
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+		else
+		{
+			// Not correct GSMSIM-payloads are included.
+			EAP_TRACE_ERROR(
+				m_am_tools, 
+				TRACE_FLAGS_GSMSIM_ERROR, 
+				(EAPL("ERROR: eap_type_gsmsim_c::handle_notification_response_message_reauthentication(): ")
+				 EAPL("Not correct GSMSIM-payloads are included ")
+				 EAPL("in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+				 m_state,
+				 get_state_string()));
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+		}
+	}
+}
+
+//--------------------------------------------------
+
+//
+EAP_FUNC_EXPORT eap_status_e eap_type_gsmsim_c::handle_notification_response_message_full_authentication(
+	const eap_am_network_id_c * const receive_network_id,
+	gsmsim_header_c * const received_gsmsim,
+	const u32_t /*gsmsim_packet_length*/,
+	gsmsim_payloads_c * const p_gsmsim_payloads)
+{
+	EAP_TRACE_DEBUG(
+		m_am_tools, 
+		TRACE_FLAGS_DEFAULT, 
+		(EAPL("send: GSMSIM-type %10s, %s, state %2d=%s\n"),
+		 EAPL("handle_notification_response_message_full_authentication"),
+		 (m_is_client) ? EAPL("client") : EAPL("server"),
+		 m_state,
+		 get_state_string()
+		 ));
+
+	// The second most significant bit of the notification code is called
+	// the Phase bit (P bit). It specifies at which phase of the EAP-SIM
+	// exchange the notification can be used.
+	if (get_gsmsim_notification_code_P_bit(m_gsmsim_notification_code) == false)
+	{
+		// If the P bit is set to zero,
+		// the notification can only be used after a successful EAP/SIM/
+		// Challenge round in full authentication or a successful EAP/SIM/
+		// Re-authentication round in reautentication. A re-authentication round
+		// is considered successful only if the peer has successfully verified
+		// AT_MAC and AT_COUNTER attributes, and does not include the
+		// AT_COUNTER_TOO_SMALL attribute in EAP-Response/SIM/Re-authentication.
+
+		// The AT_MAC attribute MUST be included if the P bit of the notification
+		// code in AT_NOTIFICATION is set to zero, and MUST NOT be included in
+		// cases when the P bit is set to one. The P bit is discussed in Section
+		// 4.4.
+
+		// Checks the payloads existence.
+		if (p_gsmsim_payloads->check_payloads(
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // nonce_mt
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // nonce_s
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_be,     // MAC
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // ENCR_DATA
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // IDENTITY
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // padding
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // n_RANDs
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // PERMANENT_ID_REQ
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // FULLAUTH_ID_REQ
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // ANY_ID_REQ
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // IV
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // NEXT_PSEUDONYM
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // NEXT_REAUTH_ID
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // NOTIFICATION
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // VERSION_LIST
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // SELECTED_VERSION
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // COUNTER
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // COUNTER_TOO_SMALL
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be,  // CLIENT_ERROR_CODE
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be  // RESULT_IND
+				) == true
+			)
+		{
+			eap_status_e status = check_message_authentication_code(
+				&m_K_aut,
+				p_gsmsim_payloads,
+				received_gsmsim,
+				received_gsmsim->get_length());
+			if (status != eap_status_ok)
+			{
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, status);
+			}
+
+			// The most significant bit is called the Failure bit (F bit).
+			// The F bit specifies whether the notification implies failure.
+			if (get_gsmsim_notification_code_F_bit(m_gsmsim_notification_code) == false)
+			{
+				// The code values with the F bit set to zero (code values 0...32767)
+				// are used on unsuccessful cases.
+				// The receipt of a notification code from this range implies failed EAP
+				// exchange, so the peer can use the notification as a failure indication.
+
+				m_last_eap_identifier = static_cast<u8_t>(m_last_eap_identifier+1u);
+				set_state(eap_type_gsmsim_state_failure);
+
+				// This will terminate session immediately.
+				get_type_partner()->set_session_timeout(0UL);
+
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, eap_status_ok);
+			}
+			else //if (get_gsmsim_notification_code_F_bit(m_gsmsim_notification_code) == true)
+			{
+				// The receipt of a notification code with the F bit set to one (values
+				// 32768...65536) does not imply failure. Notification code 32768 has
+				// been reserved as a general notification code to indicate successful
+				// authentication.
+				if (m_gsmsim_notification_code == eap_gsmsim_notification_F_set_no_P_user_authenticated)
+				{
+					status = finish_successful_authentication(
+						receive_network_id);
+
+					EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+					return EAP_STATUS_RETURN(m_am_tools, status);
+				}
+				else
+				{
+					EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+					return EAP_STATUS_RETURN(m_am_tools, eap_status_process_general_error);
+				}
+			}
+		}
+		else
+		{
+			// Not correct GSMSIM-payloads are included.
+			EAP_TRACE_ERROR(
+				m_am_tools, 
+				TRACE_FLAGS_GSMSIM_ERROR, 
+				(EAPL("ERROR: eap_type_gsmsim_c::handle_notification_response_message_full_authentication(): ")
+				 EAPL("Not correct GSMSIM-payloads are included ")
+				 EAPL("in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+				 m_state,
+				 get_state_string()));
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+		}
+	}
+	else //if (get_gsmsim_notification_code_P_bit(m_gsmsim_notification_code) == true)
+	{
+		// Checks the payloads existence.
+		if (p_gsmsim_payloads->check_payloads(
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // nonce_mt
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // nonce_s
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // MAC
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // ENCR_DATA
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // IDENTITY
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // padding
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // n_RANDs
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // PERMANENT_ID_REQ
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // FULLAUTH_ID_REQ
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // ANY_ID_REQ
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // IV
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // NEXT_PSEUDONYM
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // NEXT_REAUTH_ID
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // NOTIFICATION
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // VERSION_LIST
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // SELECTED_VERSION
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // COUNTER
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // COUNTER_TOO_SMALL
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be,  // CLIENT_ERROR_CODE
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be  // RESULT_IND
+				) == true
+			)
+		{
+			// If the P bit is set to one, the notification can only by used before
+			// the EAP/SIM/Challenge round in full authentication, or before the
+			// EAP/SIM/Re-authentication round in reauthentication.
+
+			// The most significant bit is called the Failure bit (F bit).
+			// The F bit specifies whether the notification implies failure.
+			if (get_gsmsim_notification_code_F_bit(m_gsmsim_notification_code) == false)
+			{
+				// The code values with the F bit set to zero (code values 0...32767)
+				// are used on unsuccessful cases.
+				// The receipt of a notification code from this range implies failed EAP
+				// exchange, so the peer can use the notification as a failure indication.
+			}
+			else //if (get_gsmsim_notification_code_F_bit(m_gsmsim_notification_code) == true)
+			{
+				// The receipt of a notification code with the F bit set to one (values
+				// 32768...65536) does not imply failure. Notification code 32768 has
+				// been reserved as a general notification code to indicate successful
+				// authentication.
+			}
+
+			eap_status_e status = initialize_error_message(
+				eap_status_process_general_error);
+
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+		else
+		{
+			// Not correct GSMSIM-payloads are included.
+			EAP_TRACE_ERROR(
+				m_am_tools, 
+				TRACE_FLAGS_GSMSIM_ERROR, 
+				(EAPL("ERROR: eap_type_gsmsim_c::handle_notification_response_message_full_authentication(): ")
+				 EAPL("Not correct GSMSIM-payloads are included ")
+				 EAPL("in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+				 m_state,
+				 get_state_string()));
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+		}
+	}
+}
+
+//--------------------------------------------------
+
+//
+EAP_FUNC_EXPORT eap_status_e eap_type_gsmsim_c::handle_notification_response_message(
+	const eap_am_network_id_c * const receive_network_id,
+	gsmsim_header_c * const received_gsmsim,
+	const u32_t gsmsim_packet_length,
+	gsmsim_payloads_c * const p_gsmsim_payloads)
+{
+	if (gsmsim_packet_length < received_gsmsim->get_length())
+	{
+		EAP_TRACE_ERROR(
+			m_am_tools, 
+			TRACE_FLAGS_GSMSIM_ERROR, 
+			(EAPL("ERROR: eap_type_gsmsim_c::handle_notification_response_message(): ")
+			 EAPL("gsmsim_packet_length < received_gsmsim->get_length().\n")));
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_process_illegal_packet_error);
+	}
+
+	eap_status_e status = eap_status_process_general_error;
+
+	if (m_state == eap_type_gsmsim_state_waiting_for_notification_response_success
+		|| m_state == eap_type_gsmsim_state_waiting_for_notification_response_failure)
+	{
+		// NOTE, this message is unauthenticated. Anybody could sent this message.
+
+		if (received_gsmsim->get_identifier() != m_last_eap_identifier)
+		{
+			// Wrong EAP-Identifier in this state.
+			EAP_TRACE_ERROR(
+				m_am_tools, 
+				TRACE_FLAGS_GSMSIM_ERROR, 
+				(EAPL("ERROR: eap_type_gsmsim_c::handle_notification_response_message(): ")
+				 EAPL("EAP-Identifier 0x%02x is wrong (0x%02x is correct) ")
+				 EAPL("in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+				 received_gsmsim->get_identifier(), m_last_eap_identifier, 
+				 m_state, get_state_string()));
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_eap_identity);
+		}
+
+
+		if (m_authentication_type == GSMSIM_AUTHENTICATION_TYPE_REAUTHENTICATION)
+		{
+			status = handle_notification_response_message_reauthentication(
+				receive_network_id,
+				received_gsmsim,
+				gsmsim_packet_length,
+				p_gsmsim_payloads);
+			if (status != eap_status_ok)
+			{
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, status);
+			}
+		}
+		else
+		{
+			status = handle_notification_response_message_full_authentication(
+				receive_network_id,
+				received_gsmsim,
+				gsmsim_packet_length,
+				p_gsmsim_payloads);
+			if (status != eap_status_ok)
+			{
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, status);
+			}
+		}
+
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+	else
+	{
+		// Wrong message in this state.
+		EAP_TRACE_ERROR(
+			m_am_tools, 
+			TRACE_FLAGS_GSMSIM_ERROR, 
+			(EAPL("ERROR: eap_type_gsmsim_c::handle_notification_response_message(): ")
+			 EAPL("Wrong message %d=%s in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+			 received_gsmsim->get_subtype(),
+			 received_gsmsim->get_subtype_string(),
+			 m_state,
+			 get_state_string()));
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+	}
+}
+
+//--------------------------------------------------
+
+//
+EAP_FUNC_EXPORT eap_status_e eap_type_gsmsim_c::check_challenge_response_message(
+	const eap_am_network_id_c * const receive_network_id,
+	gsmsim_header_c * const received_gsmsim,
+	const u32_t gsmsim_packet_length,
+	gsmsim_payloads_c * const p_gsmsim_payloads)
+{
+	eap_status_e status = eap_status_process_general_error;
+
+	// Checks the payloads existence.
+	if (p_gsmsim_payloads->check_payloads(
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // nonce_mt
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // nonce_s
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_be,     // MAC
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // ENCR_DATA
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // IDENTITY
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // padding
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // n_RANDs
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // PERMANENT_ID_REQ
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // FULLAUTH_ID_REQ
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // ANY_ID_REQ
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // IV
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // NEXT_PSEUDONYM
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // NEXT_REAUTH_ID
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // NOTIFICATION
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // VERSION_LIST
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // SELECTED_VERSION
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // COUNTER
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // COUNTER_TOO_SMALL
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // CLIENT_ERROR_CODE
+			gsmsim_payloads_c::eap_gsmsim_payload_status_optional     // RESULT_IND
+			) == true
+		)
+	{
+		save_current_state();
+		set_state(eap_type_gsmsim_state_analyses_challenge_response);
+
+		status = m_saved_EAP_packet.set_buffer(
+			received_gsmsim->get_header_buffer(gsmsim_packet_length),
+			gsmsim_packet_length,
+			false,
+			true);
+		if (status != eap_status_ok)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+
+		status = check_message_authentication_code(
+			&m_K_aut,
+			p_gsmsim_payloads,
+			received_gsmsim,
+			gsmsim_packet_length);
+
+		if (status == eap_status_ok)
+		{
+			// Ok, client successfully authenticated.
+			EAP_TRACE_DEBUG(
+				m_am_tools, 
+				TRACE_FLAGS_DEFAULT, 
+				(EAPL("Authentication OK.\n")));
+
+			if (m_use_result_indication == false
+				&& p_gsmsim_payloads->get_RESULT_IND()->get_payload_included() == true)
+			{
+				// ERROR: We did not send AT_RESULT_IND and client responds with it.
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_payload);
+			}
+			else if (m_use_result_indication == true
+				&& p_gsmsim_payloads->get_RESULT_IND()->get_payload_included() == false)
+			{
+				// Client does not expect result indication.
+				m_use_result_indication = false;
+			}
+
+			// Here we swap the addresses.
+			eap_am_network_id_c send_network_id(m_am_tools,
+				receive_network_id->get_destination_id(),
+				receive_network_id->get_source_id(),
+				receive_network_id->get_type());
+
+			if (m_master_session_key.get_is_valid_data() == false
+				|| m_master_session_key.get_data_length() == 0u)
+			{
+				restore_saved_previous_state();
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, eap_status_key_error);
+			}
+
+			// In order to use re-authentication, the client and the server need to
+			// store the following values: original XKEY, K_aut, K_encr, latest
+			// counter value and the next re-authentication identity.
+			status = m_am_type_gsmsim->store_reauth_parameters(
+				&m_XKEY,
+				&m_K_aut,
+				&m_K_encr,
+				EAP_TYPE_GSMSIM_INITIAL_REAUTH_COUNTER);
+			if (status != eap_status_ok)
+			{
+				restore_saved_previous_state();
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, status);
+			}
+
+			if (m_use_result_indication == true)
+			{
+				// Send EAP-Request/SIM/Notification.
+
+				eap_type_gsmsim_state_variable_e next_state = eap_type_gsmsim_state_failure;
+
+				if (m_randomly_fail_successfull_authentication == true
+					&& random_selection() == true)
+				{
+					m_gsmsim_notification_code = eap_gsmsim_notification_no_F_P_set_general_failure;
+					next_state = eap_type_gsmsim_state_waiting_for_notification_response_failure;
+				}
+				else
+				{
+					m_gsmsim_notification_code = eap_gsmsim_notification_F_set_no_P_user_authenticated;
+					next_state = eap_type_gsmsim_state_waiting_for_notification_response_success;
+				}
+
+				status = send_gsmsim_notification_request(
+					m_gsmsim_notification_code,
+					false);
+				if (status != eap_status_ok)
+				{
+					EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+					return EAP_STATUS_RETURN(m_am_tools, status);
+				}
+
+				set_state(next_state);
+			}
+			else
+			{
+				if (m_randomly_fail_successfull_authentication == true
+					&& random_selection() == true)
+				{
+					// This is for testing.
+					m_gsmsim_notification_code = eap_gsmsim_notification_no_F_no_P_general_failure;
+
+					status = initialize_notification_message();
+				}
+				else
+				{
+					// Note the EAP-Identifier of EAP-Success must be the same as
+					// EAP-Identifier in the last EAP-Request - EAP-Response roundtrip.
+					status = finish_successful_authentication(
+						receive_network_id);
+				}
+			}
+		}
+
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+	else
+	{
+		// Not correct GSMSIM-payloads are included.
+		EAP_TRACE_ERROR(
+			m_am_tools, 
+			TRACE_FLAGS_GSMSIM_ERROR, 
+			(EAPL("ERROR: eap_type_gsmsim_c::check_challenge_response_message(6): ")
+			 EAPL("Not correct GSMSIM-payloads are included in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+			 m_state,
+			 get_state_string()));
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+	}
+}
+
+
+//--------------------------------------------------
+
+//
+EAP_FUNC_EXPORT eap_status_e eap_type_gsmsim_c::handle_challenge_response_message(
+	const eap_am_network_id_c * const receive_network_id,
+	gsmsim_header_c * const received_gsmsim,
+	const u32_t gsmsim_packet_length,
+	gsmsim_payloads_c * const p_gsmsim_payloads)
+{
+	eap_status_e status = eap_status_process_general_error;
+
+	if (m_state == eap_type_gsmsim_state_waiting_for_challenge_response)
+	{
+		if (received_gsmsim->get_identifier() != m_last_eap_identifier)
+		{
+			// Wrong EAP-Identifier in this state.
+			EAP_TRACE_ERROR(
+				m_am_tools, 
+				TRACE_FLAGS_GSMSIM_ERROR, 
+				(EAPL("ERROR: eap_type_gsmsim_c::handle_challenge_response_message(): ")
+				 EAPL("EAP-Identifier 0x%02x is wrong (0x%02x is correct) ")
+				 EAPL("in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+				 received_gsmsim->get_identifier(), m_last_eap_identifier, 
+				 m_state, get_state_string()));
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_eap_identity);
+		}
+
+		status = check_challenge_response_message(
+			receive_network_id,
+			received_gsmsim,
+			gsmsim_packet_length,
+			p_gsmsim_payloads);
+	}
+	else if (m_state == eap_type_gsmsim_state_success)
+	{
+		if (received_gsmsim->get_identifier() != m_last_eap_identifier-1u)
+		{
+			// Wrong EAP-Identifier in this state.
+			EAP_TRACE_ERROR(
+				m_am_tools, 
+				TRACE_FLAGS_GSMSIM_ERROR, 
+				(EAPL("ERROR: eap_type_gsmsim_c::handle_challenge_response_message(): ")
+				 EAPL("EAP-Identifier 0x%02x is wrong (0x%02x is correct) ")
+				 EAPL("in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+				 received_gsmsim->get_identifier(),
+				 m_last_eap_identifier-1u, 
+				 m_state,
+				 get_state_string()));
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_eap_identity);
+		}
+
+		status = check_challenge_response_message(
+			receive_network_id,
+			received_gsmsim,
+			gsmsim_packet_length,
+			p_gsmsim_payloads);
+	}
+	else if (m_state == eap_type_gsmsim_state_pending_triplet_query)
+	{
+		// This is re-transmitted EAP-Response/SIM/Challenge.
+		// We dischard it quietly.
+		EAP_TRACE_DEBUG(
+			m_am_tools, 
+			TRACE_FLAGS_DEFAULT, 
+			(EAPL("WARNING: eap_type_gsmsim_c::handle_challenge_response_message(): ")
+			 EAPL("Re-transmitted message %d=%s dropped in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+			 received_gsmsim->get_subtype(),
+			 received_gsmsim->get_subtype_string(),
+			 m_state,
+			 get_state_string()));
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_drop_packet_quietly);
+	}
+	else
+	{
+		// Wrong message in this state.
+		EAP_TRACE_ERROR(
+			m_am_tools, 
+			TRACE_FLAGS_GSMSIM_ERROR, 
+			(EAPL("ERROR: eap_type_gsmsim_c::handle_challenge_response_message(): ")
+			 EAPL("Wrong message %d=%s in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+			 received_gsmsim->get_subtype(),
+			 received_gsmsim->get_subtype_string(),
+			 m_state,
+			 get_state_string()));
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+	}
+
+	EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+	return EAP_STATUS_RETURN(m_am_tools, status);
+}
+
+//--------------------------------------------------
+
+//
+EAP_FUNC_EXPORT eap_status_e eap_type_gsmsim_c::handle_reauthentication_response_message(
+	const eap_am_network_id_c * const receive_network_id,
+	gsmsim_header_c * const received_gsmsim,
+	const u32_t gsmsim_packet_length,
+	gsmsim_payloads_c * const p_gsmsim_payloads)
+{
+	eap_status_e status = eap_status_process_general_error;
+
+	EAP_TRACE_DEBUG(
+		m_am_tools,
+		TRACE_FLAGS_DEFAULT,
+		(EAPL("eap_type_gsmsim_c::handle_reauthentication_response_message(): %s, m_identity_type %d=%s, requested identity payload is %d=%s.\n"),
+		 (m_is_client == true ? "client": "server"),
+		 m_identity_type,
+		 get_identity_string(m_identity_type),
+		 m_start_response_includes_identity,
+		 gsmsim_payload_AT_header_c::get_payload_AT_string(m_start_response_includes_identity)));
+
+	if (m_state == eap_type_gsmsim_state_waiting_for_reauth_response)
+	{
+		// This could be first or retransmission request.
+
+		// Checks the payloads existence.
+		if (p_gsmsim_payloads->check_payloads(
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // nonce_mt
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // nonce_s
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_be,     // MAC
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_be,     // ENCR_DATA
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // IDENTITY
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // padding
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // n_RANDs
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // PERMANENT_ID_REQ
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // FULLAUTH_ID_REQ
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // ANY_ID_REQ
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_be,     // IV
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // NEXT_PSEUDONYM
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // NEXT_REAUTH_ID
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // NOTIFICATION
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // VERSION_LIST
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // SELECTED_VERSION
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // COUNTER
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // COUNTER_TOO_SMALL
+				gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // CLIENT_ERROR_CODE
+				gsmsim_payloads_c::eap_gsmsim_payload_status_optional     // RESULT_IND
+				) == true
+			)
+		{
+
+			m_last_eap_identifier = received_gsmsim->get_identifier();
+
+			save_current_state();
+			set_state(eap_type_gsmsim_state_analyses_reauthentication_response);
+
+			// - - - - - - - - - - - - - - - - - - - - - - - -
+
+			eap_variable_data_c orig_XKEY(m_am_tools);
+			eap_variable_data_c orig_K_aut(m_am_tools);
+			eap_variable_data_c orig_K_encr(m_am_tools);
+			u32_t reauth_counter = 0u;
+			// In order to use re-authentication, the client and the server need to
+			// store the following values: original XKEY, K_aut, K_encr, latest
+			// counter value and the next re-authentication identity.
+			status = m_am_type_gsmsim->query_reauth_parameters(
+				&orig_XKEY,
+				&orig_K_aut,
+				&orig_K_encr,
+				&reauth_counter);
+			if (status != eap_status_ok)
+			{
+				restore_saved_previous_state();
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, status);
+			}
+
+			EAP_TRACE_DEBUG(
+				m_am_tools,
+				TRACE_FLAGS_DEFAULT,
+				(EAPL("eap_type_gsmsim_c::handle_reauthentication_response_message(): %s, m_saved_reauth_counter %d.\n"),
+				 (m_is_client == true ? "client": "server"),
+				 reauth_counter));
+
+			status = check_message_authentication_code(
+				&orig_K_aut,
+				p_gsmsim_payloads,
+				received_gsmsim,
+				gsmsim_packet_length);
+			if (status != eap_status_ok)
+			{
+				restore_saved_previous_state();
+
+				eap_status_string_c status_string;
+				EAP_UNREFERENCED_PARAMETER(status_string);
+				EAP_TRACE_ERROR(
+					m_am_tools, 
+					TRACE_FLAGS_GSMSIM_ERROR, 
+					(EAPL("ERROR: Re-authentication failed: %s, state %s\n"),
+					 status_string.get_status_string(status),
+					 get_state_string()));
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, status);
+			}
+
+			// Decrypt and parse encrypted payload.
+			if (p_gsmsim_payloads->get_IV()->get_payload_included() == true
+			|| p_gsmsim_payloads->get_ENCR_DATA()->get_payload_included() == true)
+			{
+				if (p_gsmsim_payloads->get_IV()->get_payload_included() == true
+				&& p_gsmsim_payloads->get_ENCR_DATA()->get_payload_included() == true
+				&& p_gsmsim_payloads->get_MAC()->get_payload_included() == true)
+				{
+					if (m_use_result_indication == false
+						&& p_gsmsim_payloads->get_RESULT_IND()->get_payload_included() == true)
+					{
+						// ERROR: We did not send AT_RESULT_IND and client responds with it.
+						EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+						return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_payload);
+					}
+					else if (m_use_result_indication == true
+						&& p_gsmsim_payloads->get_RESULT_IND()->get_payload_included() == false)
+					{
+						// Client does not expect result indication.
+						m_use_result_indication = false;
+					}
+
+					gsmsim_payloads_c * const l_gsmsim_payloads = new gsmsim_payloads_c(m_am_tools);
+					eap_automatic_variable_c<gsmsim_payloads_c> l_gsmsim_payloads_automatic(m_am_tools, l_gsmsim_payloads);
+
+					if (l_gsmsim_payloads == 0
+						|| l_gsmsim_payloads->get_is_valid() == false)
+					{
+						EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+						return EAP_STATUS_RETURN(m_am_tools, eap_status_allocation_error);
+					}
+
+					status = decrypt_DATA_payload(
+						p_gsmsim_payloads,
+						&orig_K_encr);
+					if (status != eap_status_ok)
+					{
+						restore_saved_previous_state();
+						EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+						return EAP_STATUS_RETURN(m_am_tools, status);
+					}
+
+					u32_t state_payload_buffer_length = p_gsmsim_payloads->get_ENCR_DATA()->get_data_length();
+
+					const gsmsim_payload_AT_header_c gp_data_payload(
+						m_am_tools,
+						p_gsmsim_payloads->get_ENCR_DATA()->get_data(state_payload_buffer_length),
+						state_payload_buffer_length);
+
+					if (gp_data_payload.get_is_valid() == false)
+					{
+						EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+						return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+					}
+
+					status = parse_gsmsim_payload(
+						&gp_data_payload,
+						&state_payload_buffer_length,
+						l_gsmsim_payloads,
+						received_gsmsim->get_subtype());
+					if (status != eap_status_ok)
+					{
+						restore_saved_previous_state();
+						EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+						return EAP_STATUS_RETURN(m_am_tools, status);
+					}
+
+					if (l_gsmsim_payloads->get_COUNTER_TOO_SMALL()->get_payload_included() == true)
+					{
+						// When the client detects that the
+						// counter value is not fresh, it includes the AT_COUNTER_TOO_SMALL
+						// attribute in EAP-Response/SIM/Re-authentication. This attribute
+						// doesn't contain any data but it is a request for the server to
+						// initiate full authentication.
+
+						// The full authentication must follow.
+						m_authentication_type = GSMSIM_AUTHENTICATION_TYPE_FULL_AUTH;
+						set_start_response_includes_identity(gsmsim_payload_NONE);
+
+						bool pseudonym_decode_failed = false;
+
+						if (m_identity.get_is_valid_data() == false
+							|| (m_identity_type != GSMSIM_IDENTITY_TYPE_IMSI_ID
+								&& m_identity_type != GSMSIM_IDENTITY_TYPE_PSEUDONYM_ID
+								&& m_identity_type != GSMSIM_IDENTITY_TYPE_RE_AUTH_ID))
+						{
+							// We do not have any identity of the client.
+							set_start_response_includes_identity(gsmsim_payload_AT_FULLAUTH_ID_REQ);
+							set_identity_type(GSMSIM_IDENTITY_TYPE_NONE);
+							(void) m_identity.reset();
+							pseudonym_decode_failed = true;
+						}
+
+						status = send_start_request_message(
+							pseudonym_decode_failed,
+							static_cast<u8_t>(received_gsmsim->get_identifier()+1u));
+						if (status == eap_status_ok)
+						{
+							m_last_eap_identifier = static_cast<u8_t>(received_gsmsim->get_identifier()+1u);
+						}
+
+						EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+						return EAP_STATUS_RETURN(m_am_tools, status);
+					}
+
+
+					if (l_gsmsim_payloads->get_COUNTER()->get_payload_included() == false)
+					{
+						restore_saved_previous_state();
+						EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+						return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_payload);
+					}
+
+					u32_t counter = l_gsmsim_payloads->get_COUNTER()->get_original_header()->get_reserved();
+
+					if (counter != reauth_counter)
+					{
+						restore_saved_previous_state();
+						EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+						return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_payload);
+					}
+
+					// OK, client re-authenticates correctly.
+
+					if (m_use_result_indication == true)
+					{
+						// Send EAP-Request/SIM/Notification.
+						m_gsmsim_notification_code = eap_gsmsim_notification_F_set_no_P_user_authenticated;
+
+						status = send_gsmsim_notification_request(
+							m_gsmsim_notification_code,
+							true);
+						if (status != eap_status_ok)
+						{
+							EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+							return EAP_STATUS_RETURN(m_am_tools, status);
+						}
+
+						set_state(eap_type_gsmsim_state_waiting_for_notification_response_success);
+
+						EAP_TRACE_DEBUG(
+							m_am_tools, 
+							TRACE_FLAGS_DEFAULT|TRACE_TEST_VECTORS, 
+							(EAPL("EAP_type_GSMSIM: %s, re-authentication OK, waits result indication\n"),
+							 (m_is_client == true) ? "client": "server"));
+					}
+					else
+					{
+						if (m_randomly_fail_successfull_authentication == true
+							&& random_selection() == true)
+						{
+							// This is for testing.
+							m_gsmsim_notification_code = eap_gsmsim_notification_no_F_no_P_general_failure;
+
+							status = initialize_notification_message();
+						}
+						else
+						{
+							// In order to use re-authentication, the client and the server need to
+							// update re-authentication counter value.
+							status = m_am_type_gsmsim->increase_reauth_counter();
+							if (status != eap_status_ok)
+							{
+								EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+								return EAP_STATUS_RETURN(m_am_tools, status);
+							}
+
+							// Note the EAP-Identifier of EAP-Success must be the same as
+							// EAP-Identifier in the last EAP-Request - EAP-Response roundtrip.
+							status = finish_successful_authentication(
+								receive_network_id);
+						}
+					}
+					
+					EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+					return EAP_STATUS_RETURN(m_am_tools, status);
+				}
+				else
+				{
+					// All of these must be included
+					// or none of these must be included.
+					restore_saved_previous_state();
+					return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_payload);
+				}
+			}
+			else
+			{
+				// Not correct GSMSIM-payloads are included.
+				restore_saved_previous_state();
+				EAP_TRACE_ERROR(
+					m_am_tools, 
+					TRACE_FLAGS_GSMSIM_ERROR, 
+					(EAPL("ERROR: eap_type_gsmsim_c::handle_reauthentication_response_message(6): ")
+					 EAPL("Not correct GSMSIM-payloads are included in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+					 m_state,
+					 get_state_string()));
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+			}
+		}
+		else
+		{
+			// Not correct GSMSIM-payloads are included.
+			EAP_TRACE_ERROR(
+				m_am_tools, 
+				TRACE_FLAGS_GSMSIM_ERROR, 
+				(EAPL("ERROR: eap_type_gsmsim_c::handle_reauthentication_response_message(6): ")
+				 EAPL("Not correct GSMSIM-payloads are included in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+				 m_state,
+				 get_state_string()));
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+		}
+	}
+	else
+	{
+		// Wrong message in this state.
+		EAP_TRACE_ERROR(
+			m_am_tools, 
+			TRACE_FLAGS_GSMSIM_ERROR, 
+			(EAPL("ERROR: eap_type_gsmsim_c::handle_reauthentication_response_message(): ")
+			 EAPL("Wrong message %d=%s in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+			 received_gsmsim->get_subtype(),
+			 received_gsmsim->get_subtype_string(),
+			 m_state,
+			 get_state_string()));
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+	}
+}
+
+//--------------------------------------------------
+
+//
+EAP_FUNC_EXPORT eap_status_e eap_type_gsmsim_c::handle_client_error_response_message(
+	const eap_am_network_id_c * const /* receive_network_id */,
+	gsmsim_header_c * const received_gsmsim,
+	const u32_t gsmsim_packet_length,
+	gsmsim_payloads_c * const p_gsmsim_payloads)
+{
+	EAP_UNREFERENCED_PARAMETER(gsmsim_packet_length);
+	EAP_UNREFERENCED_PARAMETER(received_gsmsim);
+
+	eap_status_e status = eap_status_process_general_error;
+
+	// This could be first, retransmission request
+	// or some nasty attacker to make denial of service.
+
+	// Checks the payloads existence.
+	if (p_gsmsim_payloads->check_payloads(
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // nonce_mt
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // nonce_s
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // MAC
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // ENCR_DATA
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // IDENTITY
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // padding
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // n_RANDs
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // PERMANENT_ID_REQ
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // FULLAUTH_ID_REQ
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // ANY_ID_REQ
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be,     // IV
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // NEXT_PSEUDONYM
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // NEXT_REAUTH_ID
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // NOTIFICATION
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // VERSION_LIST
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // SELECTED_VERSION
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // COUNTER
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be, // COUNTER_TOO_SMALL
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_be,     // CLIENT_ERROR_CODE
+			gsmsim_payloads_c::eap_gsmsim_payload_status_must_not_be  // RESULT_IND
+			) == true
+		)
+	{
+		eap_status_e client_status = eap_status_process_general_error;
+
+		/** @{ Add some use for the Client Error Code. } */
+		eap_gsmsim_client_error_code_e client_error_code
+			= static_cast<eap_gsmsim_client_error_code_e>(p_gsmsim_payloads->get_CLIENT_ERROR_CODE()
+				->get_original_header()->get_reserved());
+
+		EAP_UNREFERENCED_PARAMETER(client_error_code);
+		
+		status = initialize_error_message(
+			client_status);
+
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+	else
+	{
+		// Not correct GSMSIM-payloads are included.
+		EAP_TRACE_ERROR(
+			m_am_tools, 
+			TRACE_FLAGS_GSMSIM_ERROR, 
+			(EAPL("ERROR: eap_type_gsmsim_c::handle_client_error_response_message(): ")
+			 EAPL("Not correct GSMSIM-payloads are included in eap_type_gsmsim_state_variable_e %d=%s.\n"),
+			 m_state,
+			 get_state_string()));
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_header_corrupted);
+	}
+}
+
+//--------------------------------------------------
+
+//
+EAP_FUNC_EXPORT eap_status_e eap_type_gsmsim_c::check_NAI(
+	const u8_t * const identity,
+	const u32_t identity_length,
+	const u8_t * const at_character)
+{
+	EAP_TRACE_BEGIN(m_am_tools, TRACE_FLAGS_DEFAULT);
+
+	bool includes_at = false;
+	bool includes_dot = false;
+	u32_t username_length = 0u;
+	u32_t realm_length = 0u;
+
+	for (u32_t ind = 0; ind < identity_length; ind++)
+	{
+		const u8_t character = identity[ind];
+
+		if (includes_at == false)
+		{
+			if (character != GSMSIM_NAI_AT_BYTE)
+			{
+				++username_length;
+			}
+		}
+		else
+		{
+			++realm_length;
+		}
+
+
+		if ('0' <= character && character <= '9')
+		{
+			// OK.
+		}
+		else if ('a' <= character && character <= 'z')
+		{
+			// OK.
+		}
+		else if ('A' <= character && character <= 'Z')
+		{
+			// OK.
+		}
+		else if (character == GSMSIM_NAI_AT_BYTE)
+		{
+			if (includes_at == false)
+			{
+				includes_at = true;
+			}
+			else
+			{
+				// Second at ('@').
+				EAP_TRACE_DATA_DEBUG(
+					m_am_tools, 
+					TRACE_FLAGS_DEFAULT, 
+					(EAPL("Illegal NAI, includes second at \'@\' character."),
+					identity,
+					identity_length));
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_nai);
+			}
+		}
+		else if (character == '.')
+		{
+			if (includes_at == true)
+			{
+				// OK.
+				includes_dot = true;
+			}
+			else
+			{
+				// dot ('.') within username
+				EAP_TRACE_DATA_DEBUG(
+					m_am_tools, 
+					TRACE_FLAGS_DEFAULT, 
+					(EAPL("Illegal NAI, dot \'.\' within username."),
+					identity,
+					identity_length));
+				EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+				return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_nai);
+			}
+		}
+		else if (character == '<'
+			|| character == '>'
+			|| character == '('
+			|| character == ')'
+			|| character == '['
+			|| character == ']'
+			|| character == '\\'
+			|| character == '.'
+			|| character == ','
+			|| character == ';'
+			|| character == ':'
+			|| character == GSMSIM_NAI_AT_BYTE
+			|| character == ' ' // space
+			|| character <= 0x1f // Ctrl
+			|| character >= 0x7f) // extented characters
+		{
+			// Illegal character.
+			EAP_TRACE_ERROR(
+				m_am_tools, 
+				TRACE_FLAGS_GSMSIM_ERROR, 
+				(EAPL("ERROR: Illegal NAI, includes illegal character 0x%02x=%c.\n"),
+				 character,
+				 character));
+			EAP_TRACE_DATA_ERROR(
+				m_am_tools, 
+				TRACE_FLAGS_DEFAULT, 
+				(EAPL("Illegal NAI, includes illegal character."),
+				 identity,
+				 identity_length));
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_nai);
+		}
+		else
+		{
+			// All other ascii values are OK.
+		}
+	}
+
+	// Note the username could be zero length.
+	if ((realm_length == 1u && includes_at == true) // one at ('@') is illegal.
+		|| (realm_length == 2u && includes_at == true && includes_dot == true)) //  one at ('@') and one dot is illegal.
+	{
+		EAP_TRACE_DATA_DEBUG(
+			m_am_tools, 
+			TRACE_FLAGS_DEFAULT, (EAPL("Illegal NAI."),
+			identity,
+			identity_length));
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_nai);
+	}
+
+	if (m_check_nai_realm == true)
+	{
+		if (at_character == 0
+			&& realm_length == 0
+			&& get_nai_realm()->get_data_length() == 0)
+		{
+			// OK, no realm.
+		}
+		else if (at_character == 0
+			|| realm_length != get_nai_realm()->get_data_length()
+			|| m_am_tools->memcmp(
+				at_character+1u,
+				get_nai_realm()->get_data(),
+				get_nai_realm()->get_data_length()) != 0)
+		{
+			EAP_TRACE_DATA_DEBUG(
+				m_am_tools, 
+				TRACE_FLAGS_DEFAULT, 
+				(EAPL("Illegal NAI, realm unknown."),
+				identity,
+				identity_length));
+			EAP_TRACE_DATA_DEBUG(
+				m_am_tools, 
+				TRACE_FLAGS_DEFAULT, 
+				(EAPL("NAI should be"),
+				get_nai_realm()->get_data(),
+				get_nai_realm()->get_data_length()));
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, eap_status_illegal_nai);
+		}
+	}
+
+
+	EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+	return EAP_STATUS_RETURN(m_am_tools, eap_status_ok);
+}
+
+//--------------------------------------------------
+
+//
+EAP_FUNC_EXPORT eap_status_e eap_type_gsmsim_c::parse_identity(
+	const u8_t * const identity,
+	const u32_t identity_length)
+{
+	EAP_TRACE_BEGIN(m_am_tools, TRACE_FLAGS_DEFAULT);
+
+	eap_status_e status(eap_status_process_general_error);
+
+	if (identity_length < 1u)
+	{
+		status = m_identity.init(0ul);
+		if (status != eap_status_ok)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+
+		status = m_NAI.init(0ul);
+		if (status != eap_status_ok)
+		{
+			EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+			return EAP_STATUS_RETURN(m_am_tools, status);
+		}
+
+		return EAP_STATUS_RETURN(m_am_tools, eap_status_ok);
+	}
+
+	const u8_t *at_character = reinterpret_cast<const u8_t *>(m_am_tools->memchr(
+		identity,
+		GSMSIM_AT_CHARACTER[0],
+		identity_length));
+
+	// NOTE, at_character could be NULL. Realm is optional.
+
+	status = check_NAI(identity, identity_length, at_character);
+	if (status != eap_status_ok)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+
+	status = eap_status_process_general_error;
+
+	u32_t username_length = identity_length;
+	if (at_character != 0)
+	{
+		username_length = static_cast<u32_t>(at_character-identity);
+	}
+
+	status = m_identity.set_copy_of_buffer(
+		identity, // Note we do store whole IMSI or pseudonym including possible prefix.
+		username_length);
+	if (status != eap_status_ok)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+
+	status = m_NAI.set_copy_of_buffer(identity, identity_length);
+	if (status != eap_status_ok)
+	{
+		EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+		return EAP_STATUS_RETURN(m_am_tools, status);
+	}
+
+	EAP_TRACE_END(m_am_tools, TRACE_FLAGS_DEFAULT);
+	return EAP_STATUS_RETURN(m_am_tools, status);
+}
+
+//--------------------------------------------------
+
+#endif //#if defined(USE_EAP_TYPE_SERVER_GSMSIM)
+
+
+
+// End.