// ----------------------------------------------------------------------------
// Copyright 2016-2017 ARM Ltd.
//
// SPDX-License-Identifier: Apache-2.0
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// ----------------------------------------------------------------------------

// fixup the compilation on ARMCC for PRId32
#define __STDC_FORMAT_MACROS
#include <inttypes.h>

#include "include/ConnectorClient.h"
#include "include/CloudClientStorage.h"
#include "include/CertificateParser.h"

#ifndef MBED_CLIENT_DISABLE_EST_FEATURE
#include "include/EstClient.h"
#endif // !MBED_CLIENT_DISABLE_EST_FEATURE

#include "MbedCloudClient.h"
#include "mbed-client/m2mconstants.h"
#include "mbed-client/m2minterfacefactory.h"
#include "mbed-client/m2mdevice.h"
#include "mbed-client/m2mconstants.h"
#include "mbed-trace/mbed_trace.h"
#include "factory_configurator_client.h"
#include "key_config_manager.h"
#include "mbed-client/uriqueryparser.h"
#include "randLIB.h"

#include <assert.h>
#include <string.h>
#include <stdio.h>

#include "ns_hal_init.h"

#ifdef MBED_CONF_MBED_CLIENT_EVENT_LOOP_SIZE
#define MBED_CLIENT_EVENT_LOOP_SIZE MBED_CONF_MBED_CLIENT_EVENT_LOOP_SIZE
#else
#define MBED_CLIENT_EVENT_LOOP_SIZE 1024
#endif

#define TRACE_GROUP "mClt"

#define INTERNAL_ENDPOINT_PARAM     "&iep="
#define DEFAULT_ENDPOINT            "endpoint"
#define INTERFACE_ERROR             "Client interface is not created. Restart"
#define CREDENTIAL_ERROR            "Failed to read credentials from storage"
#define DEVICE_NOT_PROVISIONED      "Device not provisioned"
#define CONNECTOR_ERROR_NO_MEMORY   "Not enough memory to store LWM2M credentials"
#define CONNECTOR_BOOTSTRAP_AGAIN   "Re-bootstrapping"

#ifndef MBED_CLIENT_DISABLE_EST_FEATURE
#define ERROR_EST_ENROLLMENT_REQUEST_FAILED   "EST enrollment request failed"
#define LWM2M_CSR_SUBJECT_FORMAT              "L=%s,OU=%s,CN=%s"
#endif // !MBED_CLIENT_DISABLE_EST_FEATURE

#define MAX_REBOOTSTRAP_TIMEOUT 21600 // 6 hours

// XXX: nothing here yet
class EventData {

};

static int read_callback_helper(const char *key, void *buffer, size_t *buffer_len)
{
    size_t cert_size = 0;
    if (strcmp(key, g_fcc_lwm2m_device_private_key_name) == 0 ||
        strcmp(key, g_fcc_bootstrap_device_private_key_name) == 0) {
        if (ccs_item_size(key, buffer_len, CCS_PRIVATE_KEY_ITEM) != CCS_STATUS_SUCCESS) {
            *buffer_len = 0;
            return CCS_STATUS_ERROR;
        }

        if (ccs_get_item(key, (uint8_t*)buffer, *buffer_len, &cert_size, CCS_PRIVATE_KEY_ITEM) != CCS_STATUS_SUCCESS) {
            *buffer_len = 0;
            return CCS_STATUS_ERROR;
        }
    } else {
        if (ccs_item_size(key, buffer_len, CCS_CERTIFICATE_ITEM) != CCS_STATUS_SUCCESS) {
            *buffer_len = 0;
            return CCS_STATUS_ERROR;
        }

        if (ccs_get_item(key, (uint8_t*)buffer, *buffer_len, &cert_size, CCS_CERTIFICATE_ITEM) != CCS_STATUS_SUCCESS) {
            *buffer_len = 0;
            return CCS_STATUS_ERROR;
        }
    }

    *buffer_len = cert_size;

    return CCS_STATUS_SUCCESS;
}

static bool write_security_object_data_to_kcm(const M2MResourceBase& resource, const uint8_t *buffer, const size_t buffer_size, void */*client_args*/)
{
    ccs_status_e status = CCS_STATUS_ERROR;
    uint32_t resource_id = resource.name_id();
    uint16_t object_instance_id = resource.object_instance_id();

    switch (resource_id) {
        case M2MSecurity::PublicKey:
            if (object_instance_id == M2MSecurity::Bootstrap) {
                ccs_delete_item(g_fcc_bootstrap_device_certificate_name, CCS_CERTIFICATE_ITEM);
                status = ccs_set_item(g_fcc_bootstrap_device_certificate_name, buffer, buffer_size, CCS_CERTIFICATE_ITEM);
            } else {
                ccs_delete_item(g_fcc_lwm2m_device_certificate_name, CCS_CERTIFICATE_ITEM);
                status = ccs_set_item(g_fcc_lwm2m_device_certificate_name, buffer, buffer_size, CCS_CERTIFICATE_ITEM);
            }
            break;

        case M2MSecurity::ServerPublicKey:
            if (object_instance_id == M2MSecurity::Bootstrap) {
                ccs_delete_item(g_fcc_bootstrap_server_ca_certificate_name, CCS_CERTIFICATE_ITEM);
                status = ccs_set_item(g_fcc_bootstrap_server_ca_certificate_name, buffer, buffer_size, CCS_CERTIFICATE_ITEM);
            } else {
                ccs_delete_item(g_fcc_lwm2m_server_ca_certificate_name, CCS_CERTIFICATE_ITEM);
                status = ccs_set_item(g_fcc_lwm2m_server_ca_certificate_name, buffer, buffer_size, CCS_CERTIFICATE_ITEM);
            }
            break;

        case M2MSecurity::Secretkey:
            if (object_instance_id == M2MSecurity::Bootstrap) {
                ccs_delete_item(g_fcc_bootstrap_device_private_key_name, CCS_PRIVATE_KEY_ITEM);
                status = ccs_set_item(g_fcc_bootstrap_device_private_key_name, buffer, buffer_size, CCS_PRIVATE_KEY_ITEM);
            } else {
                ccs_delete_item(g_fcc_lwm2m_device_private_key_name, CCS_PRIVATE_KEY_ITEM);
                status = ccs_set_item(g_fcc_lwm2m_device_private_key_name, buffer, buffer_size, CCS_PRIVATE_KEY_ITEM);
            }
            break;

        default:
            break;
    }

    return (status == CCS_STATUS_SUCCESS) ? true : false;
}

static int read_security_object_data_from_kcm(const M2MResourceBase& resource, void *buffer, size_t *buffer_len, void */*client_args*/)
{
    uint32_t resource_id = resource.name_id();
    uint16_t object_instance_id = resource.object_instance_id();
    switch (resource_id) {
        case M2MSecurity::PublicKey:
            if (object_instance_id == M2MSecurity::Bootstrap) {
                return read_callback_helper(g_fcc_bootstrap_device_certificate_name, buffer, buffer_len);
            } else {
                return read_callback_helper(g_fcc_lwm2m_device_certificate_name, buffer, buffer_len);
            }

        case M2MSecurity::ServerPublicKey:
            if (object_instance_id == M2MSecurity::Bootstrap) {
                return read_callback_helper(g_fcc_bootstrap_server_ca_certificate_name, buffer, buffer_len);
            } else {
                return read_callback_helper(g_fcc_lwm2m_server_ca_certificate_name, buffer, buffer_len);
            }

        case M2MSecurity::Secretkey:
            if (object_instance_id == M2MSecurity::Bootstrap) {
                return read_callback_helper(g_fcc_bootstrap_device_private_key_name, buffer, buffer_len);
            } else {
                return read_callback_helper(g_fcc_lwm2m_device_private_key_name, buffer, buffer_len);
            }

        default:
            break;
    }

    return CCS_STATUS_ERROR;
}

static int open_certificate_chain_callback(const M2MResourceBase& resource, void */*buffer*/, size_t *chain_size, void *client_args)
{
    void *handle = NULL;
    uint16_t object_instance_id = resource.object_instance_id();
    ConnectorClient *client = (ConnectorClient*)client_args;
    if (object_instance_id == M2MSecurity::Bootstrap) {
        handle = ccs_open_certificate_chain(g_fcc_bootstrap_device_certificate_name, chain_size);
        client->set_certificate_chain_handle(handle);
    } else {
        handle = ccs_open_certificate_chain(g_fcc_lwm2m_device_certificate_name, chain_size);
        client->set_certificate_chain_handle(handle);
    }

    return (handle) ? CCS_STATUS_SUCCESS : CCS_STATUS_ERROR;
}

static int read_certificate_chain_callback(const M2MResourceBase& /*resource*/, void *buffer, size_t *buffer_len, void *client_args)
{
    ConnectorClient *client = (ConnectorClient*) client_args;
    ccs_status_e status = CCS_STATUS_ERROR;
    if (client->certificate_chain_handle()) {
        status = ccs_get_next_cert_chain(client->certificate_chain_handle(), buffer, buffer_len);
    }

    return status;
}

static int close_certificate_chain_callback(const M2MResourceBase& /*resource*/, void */*buffer*/, size_t *, void *client_args)
{
    ccs_status_e status = CCS_STATUS_ERROR;
    ConnectorClient *client = (ConnectorClient*) client_args;
    if (client->certificate_chain_handle()) {
        status = ccs_close_certificate_chain(client->certificate_chain_handle());
        client->set_certificate_chain_handle(NULL);
    }
    return status;
}

ConnectorClient::ConnectorClient(ConnectorClientCallback* callback)
: _callback(callback),
  _current_state(State_Bootstrap_Start),
  _event_generated(false), _state_engine_running(false),
  _setup_complete(false),
  _interface(NULL), _security(NULL),
  _endpoint_info(M2MSecurity::Certificate), _client_objs(NULL),
  _rebootstrap_timer(*this), _bootstrap_security_instance(1),
  _lwm2m_security_instance(0), _certificate_chain_handle(NULL)
#ifndef MBED_CLIENT_DISABLE_EST_FEATURE
  ,_est_client(*this)
#endif // !MBED_CLIENT_DISABLE_EST_FEATURE

{
    assert(_callback != NULL);

    _rebootstrap_time = randLIB_get_random_in_range(1, 10);
}


ConnectorClient::~ConnectorClient()
{
    uninitialize_storage();
    M2MDevice::delete_instance();
    M2MSecurity::delete_instance();
    delete _interface;
}

bool ConnectorClient::setup()
{
    // the setup() may be called again after connection has been closed so let's avoid leaks
    if (_setup_complete == false) {

        // The ns_hal_init() needs to be called by someone before create_interface(),
        // as it will also initialize the tasklet.
        ns_hal_init(NULL, MBED_CLIENT_EVENT_LOOP_SIZE, NULL, NULL);

        // Create the lwm2m server security object we need always
        M2MSecurity *security = M2MInterfaceFactory::create_security(M2MSecurity::M2MServer);
        M2MInterface *interface = M2MInterfaceFactory::create_interface(*this,
                                                          DEFAULT_ENDPOINT,                     // endpoint name string
                                                          MBED_CLOUD_CLIENT_ENDPOINT_TYPE,      // endpoint type string
                                                          MBED_CLOUD_CLIENT_LIFETIME,           // lifetime
                                                          MBED_CLOUD_CLIENT_LISTEN_PORT,        // listen port
                                                          _endpoint_info.account_id,            // domain string
                                                          transport_mode(),                     // binding mode
                                                          M2MInterface::LwIP_IPv4);             // network stack

        if ((security == NULL) || (interface == NULL)) {
            M2MSecurity::delete_instance();
            delete interface;
        } else {
            if (initialize_storage() == CCS_STATUS_SUCCESS) {
                _security = security;
                _interface = interface;
                _setup_complete = true;
            }
        }
    }

    return _setup_complete;
}

#ifndef MBED_CLIENT_DISABLE_EST_FEATURE
const EstClient &ConnectorClient::est_client()
{
    return _est_client;
}
#endif // !MBED_CLIENT_DISABLE_EST_FEATURE

void ConnectorClient::start_bootstrap()
{
    tr_debug("ConnectorClient::start_bootstrap()");

    assert(_callback != NULL);
    assert(_setup_complete);

    init_security_object();
    // Stop rebootstrap timer if it was running
    _rebootstrap_timer.stop_timer();

    if (create_bootstrap_object()) {
        _interface->update_endpoint(_endpoint_info.endpoint_name);
        _interface->update_domain(_endpoint_info.account_id);
        internal_event(State_Bootstrap_Start);
    } else {
        tr_error("ConnectorClient::start_bootstrap() - bootstrap object fail");
    }
    state_engine();
}

void ConnectorClient::start_registration(M2MBaseList* client_objs)
{
    tr_debug("ConnectorClient::start_registration()");

    assert(_callback != NULL);
    assert(_setup_complete);

    init_security_object();
    _client_objs = client_objs;

    // XXX: actually this call should be external_event() to match the pattern used in other m2m classes
    if (create_register_object()) {
        if(_security->get_security_instance_id(M2MSecurity::M2MServer) >= 0) {
            _interface->update_endpoint(_endpoint_info.endpoint_name);
            _interface->update_domain(_endpoint_info.account_id);
            internal_event(State_Registration_Start);
        } else {
            tr_error("ConnectorClient::start_registration(): failed to create objs");
            _callback->connector_error(M2MInterface::InvalidParameters, INTERFACE_ERROR);
        }
    } else {
        tr_error("ConnectorClient::start_registration - failed to read credentials");
        _callback->connector_error((M2MInterface::Error)MbedCloudClient::ConnectorFailedToReadCredentials, CREDENTIAL_ERROR);
    }
    state_engine();
}

M2MInterface * ConnectorClient::m2m_interface()
{
    return _interface;
}

void ConnectorClient::update_registration()
{
    if(_interface && _security && _security->get_security_instance_id(M2MSecurity::M2MServer) >= 0) {
        if (_client_objs != NULL) {
            _interface->update_registration(_security, *_client_objs);
        }
        else {
            _interface->update_registration(_security);
        }
    }
}

// generates an internal event. called from within a state
// function to transition to a new state
void ConnectorClient::internal_event(StartupSubStateRegistration new_state)
{
    tr_debug("ConnectorClient::internal_event: state: %d -> %d", _current_state, new_state);
    _event_generated = true;
    _current_state = new_state;

    // Avoid recursive chain which eats too much of stack
    if (!_state_engine_running) {
        state_engine();
    }
}

// the state engine executes the state machine states
void ConnectorClient::state_engine(void)
{
    tr_debug("ConnectorClient::state_engine");

    // this simple flagging gets rid of recursive calls to this method
    _state_engine_running = true;

    // while events are being generated keep executing states
    while (_event_generated) {
        _event_generated = false;  // event used up, reset flag

        state_function(_current_state);
    }

    _state_engine_running = false;
}

void ConnectorClient::state_function(StartupSubStateRegistration current_state)
{
    switch (current_state) {
        case State_Bootstrap_Start:
            state_bootstrap_start();
            break;
        case State_Bootstrap_Started:
            state_bootstrap_started();
            break;
        case State_Bootstrap_Success:
            state_bootstrap_success();
            break;
        case State_Bootstrap_Failure:
            state_bootstrap_failure();
            break;
#ifndef MBED_CLIENT_DISABLE_EST_FEATURE
        case State_EST_Start:
            state_est_start();
            break;
        case State_EST_Started:
            state_est_started();
            break;
        case State_EST_Success:
            state_est_success();
            break;
        case State_EST_Failure:
            state_est_failure();
            break;
#endif // !MBED_CLIENT_DISABLE_EST_FEATURE
        case State_Registration_Start:
            state_registration_start();
            break;
        case State_Registration_Started:
            state_registration_started();
            break;
        case State_Registration_Success:
            state_registration_success();
            break;
        case State_Registration_Failure:
            state_registration_failure();
            break;
        case State_Unregistered:
            state_unregistered();
            break;
        default:
            break;
    }
}

/*
*  Creates register server object with mbed device server address and other parameters
*  required for client to connect to mbed device server.
*/
bool ConnectorClient::create_register_object()
{
    tr_debug("ConnectorClient::create_register_object()");
    int32_t m2m_id = _security->get_security_instance_id(M2MSecurity::M2MServer);
    if (m2m_id == -1) {
        init_security_object();
    }

    m2m_id = _security->get_security_instance_id(M2MSecurity::M2MServer);
    if (m2m_id == -1) {
        tr_error("ConnectorClient::create_register_object() - failed to read security object!");
        return false;
    }

    // Allocate scratch buffer, this will be used to copy parameters from storage to security object
    const int max_size = MAX_CERTIFICATE_SIZE;
    uint8_t *buffer = (uint8_t*)malloc(max_size);
    size_t real_size = 0;
    bool success = false;

    if (_security->set_resource_value(M2MSecurity::BootstrapServer, M2MSecurity::M2MServer, m2m_id)) {
        success = true;
    }

    // Add ResourceID's and values to the security ObjectID/ObjectInstance
    if (success) {
        success = false;
        if (_security->set_resource_value(M2MSecurity::SecurityMode, _endpoint_info.mode, m2m_id)) {
            success = true;
        }
    }

    if (success && buffer == NULL) {
        success = false;
    }

    // Endpoint
    if (success) {
        success = false;
        char device_id[64];

        size_t cert_size = max_size;
        uint8_t certificate[MAX_CERTIFICATE_SIZE];
        uint8_t *certificate_ptr = (uint8_t*)&certificate;

        // TODO! Update to use chain api
        if (_security->resource_value_buffer(M2MSecurity::PublicKey, certificate_ptr, m2m_id, &cert_size) == 0) {
            real_size = cert_size;
            if (extract_field_from_certificate((uint8_t*)certificate, real_size, "CN", device_id)) {
                tr_info("ConnectorClient::create_register_object - CN - endpoint_name : %s", device_id);
                _endpoint_info.endpoint_name = String(device_id);
                success = true;
            } else {
                tr_error("KEY_ENDPOINT_NAME failed.");
            }
        }
    }

    // Connector URL
    if (success) {
        success = false;
        if (ccs_get_item(g_fcc_lwm2m_server_uri_name, buffer, max_size, &real_size, CCS_CONFIG_ITEM) == CCS_STATUS_SUCCESS) {
            tr_info("ConnectorClient::create_register_object - M2MServerUri %.*s", (int)real_size, buffer);
            if (_security->set_resource_value(M2MSecurity::M2MServerUri, buffer, (uint32_t)real_size, m2m_id)) {
                success = true;
            }
#ifdef MBED_CLOUD_CLIENT_EDGE_EXTENSION
            _endpoint_info.lwm2m_server_uri = _security->resource_value_string(M2MSecurity::M2MServerUri, m2m_id);
#endif
        }
        else {
            tr_error("KEY_CONNECTOR_URL failed.");
        }
    }

    // Try to get internal endpoint name
    if (success) {
        if (ccs_get_item(KEY_INTERNAL_ENDPOINT, buffer, max_size, &real_size, CCS_CONFIG_ITEM) == CCS_STATUS_SUCCESS) {
            _endpoint_info.internal_endpoint_name = String((const char*)buffer, real_size);
            tr_info("ConnectorClient::create_register_object - internal endpoint name : %s", _endpoint_info.internal_endpoint_name.c_str());
        }
        else {
            tr_debug("KEY_INTERNAL_ENDPOINT failed.");
        }
    }

    if (success) {
        success = false;
        if (ccs_get_item(KEY_ACCOUNT_ID, buffer, max_size, &real_size, CCS_CONFIG_ITEM) == CCS_STATUS_SUCCESS) {
            tr_info("ConnectorClient::create_register_object - AccountId %.*s", (int)real_size, buffer);
            _endpoint_info.account_id = String((const char*)buffer, real_size);
            success = true;
        } else {
            if (ccs_get_item(g_fcc_lwm2m_server_uri_name, buffer, max_size, &real_size, CCS_CONFIG_ITEM) == CCS_STATUS_SUCCESS) {
                String address((const char*)buffer, real_size);
                if (address.size() > 0) {
                    const char *aid = NULL;
                    const int aid_size = parse_query_parameter_value_from_uri((const char*)address.c_str(), QUERY_PARAM_AID, &aid);
                    if (aid_size > 0) {
                        _endpoint_info.account_id.clear();
                        _endpoint_info.account_id.append_raw(aid, aid_size);
                        if (ccs_set_item(KEY_ACCOUNT_ID,
                                (const uint8_t*)_endpoint_info.account_id.c_str(),
                                (size_t)_endpoint_info.account_id.size(), CCS_CONFIG_ITEM) == CCS_STATUS_SUCCESS) {
                            success = true;
                            tr_info("ConnectorClient::create_register_object - aid from uri %s", _endpoint_info.account_id.c_str());
                        } else {
                            tr_error("ConnectorClient::create_register_object - failed to store aid");
                        }

                    }
                }
            }
        }
    }

    free(buffer);

    return success;
}

/*
*  Creates bootstrap server object with bootstrap server address and other parameters
*  required for connecting to mbed Cloud bootstrap server.
*/
bool ConnectorClient::create_bootstrap_object()
{
    tr_debug("ConnectorClient::create_bootstrap_object");
    bool success = false;

    // Check if bootstrap credentials are already stored in KCM
    if (bootstrap_credentials_stored_in_kcm() && _security) {
        int32_t bs_id = _security->get_security_instance_id(M2MSecurity::Bootstrap);
        if (_security->set_resource_value(M2MSecurity::SecurityMode, M2MSecurity::Certificate, bs_id)) {
            success = true;
        }

        tr_info("ConnectorClient::create_bootstrap_object - bs_id = %" PRId32, bs_id);
        tr_info("ConnectorClient::create_bootstrap_object - use credentials from storage");

        // Allocate scratch buffer, this will be used to copy parameters from storage to security object
        size_t real_size = 0;
        const int max_size = MAX_CERTIFICATE_SIZE;
        uint8_t *buffer = NULL;
        if (success) {
            success = false;
            buffer = (uint8_t*)malloc(max_size);
            if (buffer != NULL) {
                success = true;
            }
        }

        // Read internal endpoint name if it exists, we need to append
        // it to bootstrap uri if device already bootstrapped
        uint8_t *iep = NULL;
        if (success && ccs_get_string_item(KEY_INTERNAL_ENDPOINT, buffer, max_size, CCS_CONFIG_ITEM) == CCS_STATUS_SUCCESS) {
            iep = (uint8_t*)malloc(strlen((const char*)buffer) + strlen(INTERNAL_ENDPOINT_PARAM) + 1);
            if (iep != NULL) {
                strcpy((char*)iep, INTERNAL_ENDPOINT_PARAM);
                strcat((char*)iep, (const char*)buffer);
                tr_info("ConnectorClient::create_bootstrap_object - iep: %s", buffer);
            }
            //TODO: Should handle error if iep exists but allocation fails?
        }

        // Bootstrap URI
        if (success) {
            success = false;
            if (ccs_get_string_item(g_fcc_bootstrap_server_uri_name, buffer, max_size, CCS_CONFIG_ITEM) == CCS_STATUS_SUCCESS) {
                real_size = strlen((const char*)buffer);

                // Append iep if we 1. have it 2. it doesn't already exist in uri 3. it fits
                if (iep &&
                    strstr((const char*)buffer, (const char*)iep) == NULL &&
                    (real_size + strlen((const char*)iep) + 1) <= max_size) {
                    strcat((char*)buffer, (const char*)iep);
                    real_size += strlen((const char*)iep) + 1;
                }

                tr_info("ConnectorClient::create_bootstrap_object - M2MServerUri %.*s", (int)real_size, buffer);
                if (_security->set_resource_value(M2MSecurity::M2MServerUri, buffer, real_size, bs_id)) {
                    success = true;
                }
            }
        }

        free(iep);

        // Endpoint
        if (success) {
            success = false;
            if (ccs_get_item(g_fcc_endpoint_parameter_name, buffer, max_size, &real_size, CCS_CONFIG_ITEM) == CCS_STATUS_SUCCESS) {
                success = true;
                _endpoint_info.endpoint_name = String((const char*)buffer, real_size);
                tr_info("ConnectorClient::create_bootstrap_object - Endpoint %s", _endpoint_info.endpoint_name.c_str());
            }
        }

        // Account ID, not mandatory
        if (success) {
            if (ccs_get_item(KEY_ACCOUNT_ID, buffer, max_size, &real_size, CCS_CONFIG_ITEM) == CCS_STATUS_SUCCESS) {
                _endpoint_info.account_id = String((const char*)buffer, real_size);
                tr_info("ConnectorClient::create_bootstrap_object - AccountId %s", _endpoint_info.account_id.c_str());
            }
        }

        free(buffer);

        if (!success) {
            tr_error("ConnectorClient::create_bootstrap_object - Failed to read credentials");
            _callback->connector_error((M2MInterface::Error)MbedCloudClient::ConnectorFailedToReadCredentials,CREDENTIAL_ERROR);
            _security->remove_object_instance(bs_id);
        }
    } else {
        success = true;
        tr_info("ConnectorClient::create_bootstrap_object - bootstrap object already done");
    }


    return success;
}

void ConnectorClient::state_bootstrap_start()
{
    tr_info("ConnectorClient::state_bootstrap_start()");
    assert(_interface != NULL);
    assert(_security != NULL);

    _interface->bootstrap(_security);

    internal_event(State_Bootstrap_Started);
}

void ConnectorClient::state_bootstrap_started()
{
    // this state may be useful only for verifying the callbacks?
}

void ConnectorClient::state_bootstrap_success()
{
    assert(_callback != NULL);
    // Parse internal endpoint name from mDS cert
    _callback->registration_process_result(State_Bootstrap_Success);
}

void ConnectorClient::state_bootstrap_failure()
{
    assert(_callback != NULL);
    // maybe some additional canceling and/or leanup is needed here?
    _callback->registration_process_result(State_Bootstrap_Failure);
}

#ifndef MBED_CLIENT_DISABLE_EST_FEATURE
void ConnectorClient::state_est_start()
{
    // - Generate CSR from data during bootstrap phase
    // - Call EST enrollment API from InterfaceImpl

    // Update the internal endpoint name and account id to endpoint info structure
    // as we get those during bootstrap phase
    _endpoint_info.internal_endpoint_name = _interface->internal_endpoint_name();

    int32_t m2m_id = _security->get_security_instance_id(M2MSecurity::M2MServer);
    int32_t sec_mode = M2MSecurity::SecurityNotSet;
    if (m2m_id >= 0) {
        sec_mode = _security->resource_value_int(M2MSecurity::SecurityMode, m2m_id);

        // We need to parse account id from lwm2m server uri query if it is not yet
        // set in endpoint info structure
        if (_endpoint_info.account_id.length() <= 0) {
            String address = _security->resource_value_string(M2MSecurity::M2MServerUri, m2m_id);
            tr_debug("ConnectorClient::state_est_start - address: %s", address.c_str());
            if (address.size() > 0) {
                const char *aid = NULL;
                const int aid_size = parse_query_parameter_value_from_uri((const char*)address.c_str(), QUERY_PARAM_AID, &aid);
                if (aid_size > 0) {
                    _endpoint_info.account_id.append_raw(aid, aid_size);
                }
            }
        }
    }

    tr_debug("ConnectorClient::state_est_start - security instance id: %" PRId32, m2m_id);
    tr_debug("ConnectorClient::state_est_start - ep: %s", _endpoint_info.internal_endpoint_name.c_str());
    tr_debug("ConnectorClient::state_est_start - iep: %s", _endpoint_info.endpoint_name.c_str());
    tr_debug("ConnectorClient::state_est_start - aid: %s", _endpoint_info.account_id.c_str());

    // Check EST required parameters are in place
    if (m2m_id < 0 ||
        _endpoint_info.endpoint_name.length() <= 0 ||
        _endpoint_info.internal_endpoint_name.length() <= 0 ||
        _endpoint_info.account_id.length() <= 0) {
        tr_error("ConnectorClient::state_est_start - Missing parameters for EST enrollment!");
        internal_event(State_EST_Failure);
        return;
    }

    uint32_t is_bs_server = _security->resource_value_int(M2MSecurity::BootstrapServer, m2m_id);
    size_t public_key_size = MAX_CERTIFICATE_SIZE;
    size_t server_key_size = MAX_CERTIFICATE_SIZE;
    size_t private_key_size = MAX_CERTIFICATE_SIZE;

    // Temp buffer for storing CSR and certificates
    uint8_t *buffer = (uint8_t*)malloc(MAX_CERTIFICATE_SIZE);
    size_t real_size = 0;
    if (buffer == NULL) {
        tr_error("ConnectorClient::state_est_start - Allocating temp buffer failed!");
        internal_event(State_EST_Failure);
        return;
    }
    uint8_t *buffer_ptr = buffer;

    // TODO! Update to use chain api
    if (_security->resource_value_buffer(M2MSecurity::PublicKey, buffer_ptr, m2m_id, &public_key_size) != 0) {
        public_key_size = 0;
    }
    if (_security->resource_value_buffer(M2MSecurity::ServerPublicKey, buffer_ptr, m2m_id, &server_key_size) != 0) {
        server_key_size = 0;
    }
    if (_security->resource_value_buffer(M2MSecurity::Secretkey, buffer_ptr, m2m_id, &private_key_size) != 0) {
        private_key_size = 0;
    }

    tr_info("est check - is bs server /0/1: %" PRIu32, is_bs_server);
    tr_info("est check - Security Mode /0/2: %" PRIu32, sec_mode);
    tr_info("est check - Public key size /0/3: %lu", (unsigned long)public_key_size);
    tr_info("est check - Server Public key size /0/4: %lu", (unsigned long)server_key_size);
    tr_info("est check - Secret key size /0/5: %lu", (unsigned long)private_key_size);

    // Configure CSR params
    kcm_csr_params_s csr_params;
    int subject_size = snprintf(NULL, 0, LWM2M_CSR_SUBJECT_FORMAT,
                                _endpoint_info.internal_endpoint_name.c_str(),
                                _endpoint_info.account_id.c_str(),
                                _endpoint_info.endpoint_name.c_str());
    if (subject_size <= 0) {
        tr_error("ConnectorClient::state_est_start - CSR Subject formatting failed!");
        free(buffer);
        internal_event(State_EST_Failure);
        return;
    }

    // For null-terminator
    subject_size++;

    csr_params.subject = (char*)malloc(subject_size);
    if (csr_params.subject == NULL) {
        tr_error("ConnectorClient::state_est_start - CSR Subject formatting failed!");
        free(buffer);
        internal_event(State_EST_Failure);
        return;
    }

    snprintf(csr_params.subject, subject_size, LWM2M_CSR_SUBJECT_FORMAT,
             _endpoint_info.internal_endpoint_name.c_str(),
             _endpoint_info.account_id.c_str(),
             _endpoint_info.endpoint_name.c_str());

    csr_params.md_type = KCM_MD_SHA256;
    csr_params.key_usage = KCM_CSR_KU_NONE;
    csr_params.ext_key_usage = KCM_CSR_EXT_KU_NONE;

    // Delete existing keys
    ccs_delete_item(g_fcc_lwm2m_device_certificate_name, CCS_CERTIFICATE_ITEM);
    ccs_delete_item(g_fcc_lwm2m_device_private_key_name, CCS_PRIVATE_KEY_ITEM);

    kcm_status_e status = kcm_generate_keys_and_csr(KCM_SCHEME_EC_SECP256R1,
                                                    (const uint8_t*)g_fcc_lwm2m_device_private_key_name,
                                                    strlen(g_fcc_lwm2m_device_private_key_name),
                                                    NULL,
                                                    0,
                                                    false,
                                                    &csr_params,
                                                    buffer,
                                                    MAX_CERTIFICATE_SIZE,
                                                    &real_size,
                                                    NULL);

    free(csr_params.subject);

    if (status != KCM_STATUS_SUCCESS) {
        tr_error("ConnectorClient::state_est_start - Generating keys and csr failed!");
        free(buffer);
        internal_event(State_EST_Failure);
        return;
    }

    // Update state and start the enrollment by sending the enroll request
    internal_event(State_EST_Started);
    est_status_e est_status = _est_client.est_request_enrollment(NULL,
                                                                 0,
                                                                 buffer,
                                                                 real_size,
                                                                 ConnectorClient::est_enrollment_result,
                                                                 this);

    if (est_status != EST_STATUS_SUCCESS) {
        tr_error("ConnectorClient::state_est_start - EST enrollment failed with error %d", (int)est_status);
        internal_event(State_EST_Failure);
    }

    free(buffer);
}

void ConnectorClient::state_est_started()
{
}

void ConnectorClient::state_est_success()
{
    tr_info("ConnectorClient::state_est_success()");
    _interface->finish_bootstrap();
}

void ConnectorClient::state_est_failure()
{
    tr_info("ConnectorClient::state_est_failure()");
    internal_event(State_Bootstrap_Failure);
    //Failed to store credentials, bootstrap failed
    _callback->connector_error(M2MInterface::ESTEnrollmentFailed, ERROR_EST_ENROLLMENT_REQUEST_FAILED); // Translated to error code ConnectMemoryConnectFail
}
#endif /* !MBED_CLIENT_DISABLE_EST_FEATURE */

void ConnectorClient::state_registration_start()
{
    tr_info("ConnectorClient::state_registration_start()");
    assert(_interface != NULL);
    assert(_security != NULL);
    _interface->register_object(_security, *_client_objs);
    internal_event(State_Registration_Started);
}

void ConnectorClient::state_registration_started()
{
    // this state may be useful only for verifying the callbacks?
}

void ConnectorClient::state_registration_success()
{
    assert(_callback != NULL);
    _endpoint_info.internal_endpoint_name = _interface->internal_endpoint_name();

    //The endpoint is maximum 32 character long, we put bigger buffer for future extensions
    const int max_size = 64;
    uint8_t *buffer = NULL;
    buffer = (uint8_t*)malloc(max_size);

    if(!buffer) {
         _callback->registration_process_result(State_Registration_Failure);
         return;
    }
    bool no_param_update = true;

    if(ccs_get_string_item(KEY_INTERNAL_ENDPOINT, buffer, max_size, CCS_CONFIG_ITEM) == CCS_STATUS_SUCCESS) {
        if (strcmp((const char*)buffer, _endpoint_info.internal_endpoint_name.c_str()) != 0) {
            // Update is required as the stored KCM entry is different than _endpoint_info.internal_endpoint_name.
            no_param_update = false;
        }
    }
    free(buffer);

    // Update INTERNAL_ENDPOINT setting only if there is no such entry or the value is not matching the
    // _endpoint_info.internal_endpoint_name.
    if(!no_param_update) {
        ccs_delete_item(KEY_INTERNAL_ENDPOINT, CCS_CONFIG_ITEM);
        ccs_set_item(KEY_INTERNAL_ENDPOINT, (const uint8_t*)_endpoint_info.internal_endpoint_name.c_str(),
                             (size_t)_endpoint_info.internal_endpoint_name.size(),
                             CCS_CONFIG_ITEM);
    }

    _rebootstrap_time = randLIB_get_random_in_range(1, 10);
    _callback->registration_process_result(State_Registration_Success);
}

void ConnectorClient::state_registration_failure()
{
    assert(_callback != NULL);
    // maybe some additional canceling and/or leanup is needed here?
    _callback->registration_process_result(State_Registration_Failure);
}

void ConnectorClient::state_unregistered()
{
    assert(_callback != NULL);
    _callback->registration_process_result(State_Unregistered);
}

void ConnectorClient::bootstrap_data_ready(M2MSecurity *security_object)
{
    tr_info("ConnectorClient::bootstrap_data_ready");
    if(security_object) {
        // Update bootstrap credentials (we could skip this if we knew whether they were updated)
        // This will also update the address in case of first to claim
        ccs_status_e status = set_bootstrap_credentials(security_object);
        if (status != CCS_STATUS_SUCCESS) {
            // TODO: what now?
            tr_error("ConnectorClient::bootstrap_data_ready - could not store bootstrap credentials");
        }

        // Clear the first to claim flag if it's active
        if (is_first_to_claim()) {
            status = clear_first_to_claim();
            if (status != CCS_STATUS_SUCCESS) {
                // TODO: what now?
                tr_error("ConnectorClient::bootstrap_data_ready - couldn't clear first to claim flag!");
            }
        }

        // Bootstrap might delete m2mserver security object instance completely to force bootstrap
        // with new credentials, in that case delete the stored lwm2m credentials as well and re-bootstrap
        if (security_object->get_security_instance_id(M2MSecurity::M2MServer) == -1) {
            bootstrap_again();
            return;
        }
        // Bootstrap wrote M2MServer credentials, store them and also update first to claim status if it's configured
        else {
#ifndef MBED_CLIENT_DISABLE_EST_FEATURE
            int32_t m2m_id = _security->get_security_instance_id(M2MSecurity::M2MServer);
            if (m2m_id >= 0 &&
                _security->resource_value_int(M2MSecurity::SecurityMode, m2m_id) == M2MSecurity::EST) {
                // If EST is supported, continue to EST state to start EST enrollment
                tr_info("ConnectorClient::bootstrap_data_ready() - Continue to EST enrollment");
                internal_event(State_EST_Start);
                return;
            }
#endif // MBED_CLIENT_DISABLE_EST_FEATURE
            // Security mode was not EST, in that case just store the received credentials
            tr_info("ConnectorClient::bootstrap_data_ready() - Storing lwm2m credentials");
            status = set_connector_credentials(security_object);
        }

        if (status != CCS_STATUS_SUCCESS) {
            internal_event(State_Bootstrap_Failure);
            //Failed to store credentials, bootstrap failed
            _callback->connector_error(M2MInterface::MemoryFail, CONNECTOR_ERROR_NO_MEMORY); // Translated to error code ConnectMemoryConnectFail
            return;
        } else {
            tr_info("ConnectorClient::bootstrap_data_ready - set_credentials status %d", status);
        }
    }
}

void ConnectorClient::bootstrap_done(M2MSecurity *security_object)
{
    tr_info("ConnectorClient::bootstrap_done");
    internal_event(State_Bootstrap_Success);
}

void ConnectorClient::object_registered(M2MSecurity *security_object, const M2MServer &server_object)
{
    internal_event(State_Registration_Success);
}

void ConnectorClient::object_unregistered(M2MSecurity *server_object)
{
    internal_event(State_Unregistered);
}

void ConnectorClient::registration_updated(M2MSecurity *security_object, const M2MServer & server_object)
{
    _callback->registration_process_result(State_Registration_Updated);
}

void ConnectorClient::error(M2MInterface::Error error)
{
    tr_error("ConnectorClient::error() - error: %d", error);
    assert(_callback != NULL);

    if (_current_state >= State_Registration_Start &&
        use_bootstrap() &&
        (error == M2MInterface::SecureConnectionFailed ||
         error == M2MInterface::InvalidParameters)) {
        tr_info("ConnectorClient::error() - Error during lwm2m registration");

        // Delete the lwm2m security instance
        int32_t id = _security->get_security_instance_id(M2MSecurity::M2MServer);
        if (id >= 0) {
            _security->remove_object_instance(id);
        }

        bootstrap_again();
    }
    else {
        _callback->connector_error(error, _interface->error_description());
    }
}

void ConnectorClient::value_updated(M2MBase *base, M2MBase::BaseType type)
{
    assert(_callback != NULL);
    _callback->value_updated(base, type);
}

bool ConnectorClient::connector_credentials_available()
{
    tr_debug("ConnectorClient::connector_credentials_available");
    if (ccs_check_item(g_fcc_lwm2m_server_uri_name, CCS_CONFIG_ITEM) != CCS_STATUS_SUCCESS) {
        return false;
    }
    return true;
}

bool ConnectorClient::use_bootstrap()
{
    tr_debug("ConnectorClient::use_bootstrap");
    size_t real_size = 0;
    uint8_t data[CONFIG_BOOLEAN_ITEM_SIZE] = {0};
    uint32_t value = 0;
    ccs_status_e status = ccs_get_item(g_fcc_use_bootstrap_parameter_name, data, CONFIG_BOOLEAN_ITEM_SIZE, &real_size, CCS_CONFIG_ITEM);
    if (status == CCS_STATUS_SUCCESS) {
        memcpy(&value, data, CONFIG_BOOLEAN_ITEM_SIZE);
        // Return true if use_bootstrap is set
        if (value == 1) {
            return true;
        }
    }
    return false;
}


bool ConnectorClient::get_key(const char *key, const char *endpoint, char *&key_name)
{
    if(key_name) {
        free(key_name);
        key_name = NULL;
    }

    key_name = (char*)malloc(strlen(key)+strlen(endpoint)+1);
    if(key_name) {
        strcpy(key_name, key);
        strcat(key_name, endpoint);
        tr_debug("key %s", key_name);
        return true;
    }
    return false;
}

ccs_status_e ConnectorClient::set_connector_credentials(M2MSecurity *security)
{
    tr_debug("ConnectorClient::set_connector_credentials");
    ccs_status_e status = CCS_STATUS_ERROR;

    int32_t m2m_id = security->get_security_instance_id(M2MSecurity::M2MServer);
    if (m2m_id == -1) {
        return status;
    }

    size_t buffer_size = MAX_CERTIFICATE_SIZE;
    uint8_t public_key[MAX_CERTIFICATE_SIZE];
    uint8_t *public_key_ptr = (uint8_t*)&public_key;

    // TODO! Update to use chain api
    if (security->resource_value_buffer(M2MSecurity::PublicKey, public_key_ptr, m2m_id, &buffer_size) != 0) {
        return status;
    }

    char device_id[64];
    memset(device_id, 0, 64);
    if (extract_field_from_certificate(public_key, buffer_size, "L", device_id)) {
        tr_info("ConnectorClient::set_connector_credentials - L internal_endpoint_name : %s", device_id);
        _endpoint_info.internal_endpoint_name = String(device_id);
        ccs_delete_item(KEY_INTERNAL_ENDPOINT, CCS_CONFIG_ITEM);
        status = ccs_set_item(KEY_INTERNAL_ENDPOINT,(uint8_t*)device_id, strlen(device_id), CCS_CONFIG_ITEM);
    }

    memset(device_id, 0, 64);
    if (extract_field_from_certificate(public_key, buffer_size, "CN", device_id)) {
        tr_info("ConnectorClient::set_connector_credentials - CN endpoint_name : %s", device_id);
        _endpoint_info.endpoint_name = String(device_id);
    }

    if(status == CCS_STATUS_SUCCESS) {
        ccs_delete_item(KEY_ACCOUNT_ID, CCS_CONFIG_ITEM);
        // AccountID optional so don't fail if unable to store
        ccs_set_item(KEY_ACCOUNT_ID,
                     (const uint8_t*)_endpoint_info.account_id.c_str(),
                     (size_t)_endpoint_info.account_id.size(),
                     CCS_CONFIG_ITEM);
    }

    if (status == CCS_STATUS_SUCCESS) {
#ifdef MBED_CLOUD_CLIENT_EDGE_EXTENSION
        _endpoint_info.lwm2m_server_uri = security->resource_value_string(M2MSecurity::M2MServerUri, m2m_id);
#endif
        ccs_delete_item(g_fcc_lwm2m_server_uri_name, CCS_CONFIG_ITEM);
        status = ccs_set_item(g_fcc_lwm2m_server_uri_name,
                              (const uint8_t*)security->resource_value_string(M2MSecurity::M2MServerUri, m2m_id).c_str(),
                              (size_t)security->resource_value_string(M2MSecurity::M2MServerUri, m2m_id).size(),
                              CCS_CONFIG_ITEM);
    }

    M2MDevice *device = M2MInterfaceFactory::create_device();
    if (status == CCS_STATUS_SUCCESS && device) {
        String temp = "";
        uint32_t currenttime = (uint32_t)device->resource_value_int(M2MDevice::CurrentTime, 0);
        uint8_t data[4];
        memcpy(data, &currenttime, 4);
        ccs_delete_item(g_fcc_current_time_parameter_name, CCS_CONFIG_ITEM);
        ccs_set_item(g_fcc_current_time_parameter_name, data, 4, CCS_CONFIG_ITEM);

        temp = device->resource_value_string(M2MDevice::Timezone, 0);
        if (temp.size() > 0) {
            ccs_delete_item(g_fcc_device_time_zone_parameter_name, CCS_CONFIG_ITEM);
            ccs_set_item(g_fcc_device_time_zone_parameter_name, (const uint8_t*)temp.c_str(), temp.size(), CCS_CONFIG_ITEM);
        }

        temp = device->resource_value_string(M2MDevice::UTCOffset, 0);
        if (temp.size() > 0) {
            ccs_delete_item(g_fcc_offset_from_utc_parameter_name, CCS_CONFIG_ITEM);
            ccs_set_item(g_fcc_offset_from_utc_parameter_name, (const uint8_t*)temp.c_str(), temp.size(), CCS_CONFIG_ITEM);
        }

        status = CCS_STATUS_SUCCESS;
    }
    else {
        tr_debug("No device object to store!");
    }

    return status;
}

ccs_status_e ConnectorClient::set_bootstrap_credentials(M2MSecurity *security)
{
    tr_debug("ConnectorClient::set_bootstrap_credentials");
    ccs_status_e status = CCS_STATUS_ERROR;

    size_t uri_size = MAX_CERTIFICATE_SIZE;
    uint8_t bootstrap_uri[MAX_CERTIFICATE_SIZE];
    uint8_t *bootstrap_uri_ptr = (uint8_t*)&bootstrap_uri;

    int32_t bs_id = security->get_security_instance_id(M2MSecurity::Bootstrap);
    if (bs_id == -1) {
        return status;
    }

    String bs_uri = security->resource_value_string(M2MSecurity::M2MServerUri, bs_id);
    if (bs_uri.size() <= 0) {
        return status;
    }

    // Update BS uri only if it has changed.
    // If uri is missing or some other error while reading the item --> return error.
    if (ccs_get_string_item(g_fcc_bootstrap_server_uri_name, bootstrap_uri_ptr, uri_size, CCS_CONFIG_ITEM) == CCS_STATUS_SUCCESS) {
        if (strcmp((const char*)bootstrap_uri_ptr, bs_uri.c_str()) != 0) {
            tr_info("ConnectorClient::set_bootstrap_credentials - update uri from: %s to: %s", (char*)bootstrap_uri_ptr, bs_uri.c_str());
            ccs_delete_item(g_fcc_bootstrap_server_uri_name, CCS_CONFIG_ITEM);
            status = ccs_set_item(g_fcc_bootstrap_server_uri_name,
                              (const uint8_t*)bs_uri.c_str(),
                              strlen(bs_uri.c_str()),
                              CCS_CONFIG_ITEM);
        } else {
            status = CCS_STATUS_SUCCESS;
        }
    }

    return status;
}

ccs_status_e ConnectorClient::clear_first_to_claim()
{
    tr_debug("ConnectorClient::clear_first_to_claim");
    return ccs_delete_item(KEY_FIRST_TO_CLAIM, CCS_CONFIG_ITEM);
}


const ConnectorClientEndpointInfo *ConnectorClient::endpoint_info() const
{
    return &_endpoint_info;
}

bool ConnectorClient::bootstrap_credentials_stored_in_kcm()
{
    size_t real_size = 0;
    ccs_status_e success = ccs_item_size(g_fcc_bootstrap_server_uri_name, &real_size, CCS_CONFIG_ITEM);
    // Return true if bootstrap uri exists in KCM
    if ((success == CCS_STATUS_SUCCESS) && real_size > 0) {
        return true;
    } else {
        return false;
    }
}

bool ConnectorClient::is_first_to_claim()
{
    size_t real_size = 0;
    uint8_t data[CONFIG_BOOLEAN_ITEM_SIZE] = {0};
    uint32_t value = 0;
    ccs_status_e status = ccs_get_item(KEY_FIRST_TO_CLAIM, data, CONFIG_BOOLEAN_ITEM_SIZE, &real_size, CCS_CONFIG_ITEM);
    if (status == CCS_STATUS_SUCCESS) {
        memcpy(&value, data, CONFIG_BOOLEAN_ITEM_SIZE);
        // Return true if first to claim is set
        if (value == 1) {
            return true;
        }
    }
    return false;
}

void ConnectorClient::timer_expired(M2MTimerObserver::Type type)
{
    if (type == M2MTimerObserver::BootstrapFlowTimer) {
        start_bootstrap();
    }
}

#ifndef MBED_CLIENT_DISABLE_EST_FEATURE
void ConnectorClient::est_enrollment_result(est_enrollment_result_e result,
                                            cert_chain_context_s *cert_chain,
                                            void *context)
{
    tr_debug("ConnectorClient::est_enrollment_result - %s", result == EST_ENROLLMENT_SUCCESS ? "successful" : "failed");
    if (result == EST_ENROLLMENT_SUCCESS) {
        tr_debug("ConnectorClient::est_enrollment_result - PublicKey size %d", cert_chain->chain_length);
    }

    ConnectorClient *cc = static_cast<ConnectorClient*>(context);
    assert(cc);
    assert(cc->_security != NULL);

    int32_t m2m_id = cc->_security->get_security_instance_id(M2MSecurity::M2MServer);
    StartupSubStateRegistration state = State_EST_Failure;

    if (result == EST_ENROLLMENT_SUCCESS &&
        m2m_id >= 0 &&
        cert_chain != NULL &&
        cert_chain->chain_length > 0)
    {

        kcm_cert_chain_handle chain_handle;
        kcm_status_e status = kcm_cert_chain_create(&chain_handle,
                                       (const uint8_t*)g_fcc_lwm2m_device_certificate_name,
                                       strlen(g_fcc_lwm2m_device_certificate_name),
                                       cert_chain->chain_length,
                                       false);
        tr_debug("Cert chain create %d", status);
        if (status == KCM_STATUS_SUCCESS) {
            cert_context_s *cert = cert_chain->certs;
            while (cert != NULL) {

                // Store certificate
                status = kcm_cert_chain_add_next(chain_handle, cert->cert, cert->cert_length);
                if (status != KCM_STATUS_SUCCESS) {
                    break;
                }

                cert = cert->next;
            }

            status = kcm_cert_chain_close(chain_handle);
            if (status == KCM_STATUS_SUCCESS) {
                tr_info("ConnectorClient::est_enrollment_result() - Certificates stored successfully");
                tr_info("ConnectorClient::est_enrollment_result() - Storing lwm2m credentials");
                if (cc->set_connector_credentials(cc->_security) == CCS_STATUS_SUCCESS) {
                    state = State_EST_Success;
                }
            }
            else {
                tr_error("ConnectorClient::est_enrollment_result - storing certificate chain failed!");
            }
        }
    }

    // Finally free the certificate chain context
    EstClient::free_cert_chain_context(cert_chain);

    cc->internal_event(state);
}
#endif /* !MBED_CLIENT_DISABLE_EST_FEATURE */


M2MInterface::BindingMode ConnectorClient::transport_mode()
{
#ifdef MBED_CLOUD_CLIENT_TRANSPORT_MODE_UDP
    return M2MInterface::UDP;
#elif defined MBED_CLOUD_CLIENT_TRANSPORT_MODE_TCP
    return M2MInterface::TCP;
#elif defined MBED_CLOUD_CLIENT_TRANSPORT_MODE_UDP_QUEUE
    return M2MInterface::UDP_QUEUE;
#elif defined MBED_CLOUD_CLIENT_TRANSPORT_MODE_TCP_QUEUE
    return M2MInterface::TCP_QUEUE;
#else
    return M2MInterface::UDP;
#endif
}

void ConnectorClient::init_security_object()
{
    if (_security) {
        for (int i = 0; i <= M2MSecurity::Bootstrap; i++) {
            // _security->create_object_instance() returns NULL if object already exists
            if (_security->create_object_instance((M2MSecurity::ServerType)i)) {
                M2MResource* res = _security->get_resource(M2MSecurity::ServerPublicKey, i);
                if (res) {
                    res->set_resource_read_callback(read_security_object_data_from_kcm, this);
                    res->set_resource_write_callback(write_security_object_data_to_kcm, this);
                }

                res = _security->get_resource(M2MSecurity::PublicKey, i);
                if (res) {
                    res->set_resource_read_callback(read_security_object_data_from_kcm, this);
                    res->set_resource_write_callback(write_security_object_data_to_kcm, this);
                }

                res = _security->get_resource(M2MSecurity::Secretkey, i);
                if (res) {
                    res->set_resource_read_callback(read_security_object_data_from_kcm, this);
                    res->set_resource_write_callback(write_security_object_data_to_kcm, this);
                }

                res = _security->get_resource(M2MSecurity::OpenCertificateChain, i);
                if (res) {
                    res->set_resource_read_callback(open_certificate_chain_callback, this);
                }

                res = _security->get_resource(M2MSecurity::ReadDeviceCertificateChain, i);
                if (res) {
                    res->set_resource_read_callback(read_certificate_chain_callback, this);
                }

                res = _security->get_resource(M2MSecurity::CloseCertificateChain, i);
                if (res) {
                    res->set_resource_read_callback(close_certificate_chain_callback, this);
                }
            }
        }
    }
}

void *ConnectorClient::certificate_chain_handle() const
{
    return _certificate_chain_handle;
}

void ConnectorClient::set_certificate_chain_handle(void *cert_handle)
{
    _certificate_chain_handle = cert_handle;
}

void ConnectorClient::bootstrap_again()
{
    // delete the old connector credentials
    ccs_delete_item(g_fcc_lwm2m_server_uri_name, CCS_CONFIG_ITEM);
    ccs_delete_item(g_fcc_lwm2m_server_ca_certificate_name, CCS_CERTIFICATE_ITEM);
    ccs_delete_item(g_fcc_lwm2m_device_certificate_name, CCS_CERTIFICATE_ITEM);
    ccs_delete_item(g_fcc_lwm2m_device_private_key_name, CCS_PRIVATE_KEY_ITEM);

    tr_error("ConnectorClient::bootstrap_again in %d seconds", _rebootstrap_time);

    _rebootstrap_timer.start_timer(_rebootstrap_time * 1000, M2MTimerObserver::BootstrapFlowTimer, true);
    _rebootstrap_time *= 2;
    if (_rebootstrap_time > MAX_REBOOTSTRAP_TIMEOUT) {
        _rebootstrap_time = MAX_REBOOTSTRAP_TIMEOUT;
    }

    _callback->connector_error(M2MInterface::SecureConnectionFailed, CONNECTOR_BOOTSTRAP_AGAIN);
}
