m2mconnectionhandler.h

00001 /*
00002  * Copyright (c) 2015 ARM Limited. All rights reserved.
00003  * SPDX-License-Identifier: Apache-2.0
00004  * Licensed under the Apache License, Version 2.0 (the License); you may
00005  * not use this file except in compliance with the License.
00006  * You may obtain a copy of the License at
00007  *
00008  * http://www.apache.org/licenses/LICENSE-2.0
00009  *
00010  * Unless required by applicable law or agreed to in writing, software
00011  * distributed under the License is distributed on an AS IS BASIS, WITHOUT
00012  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00013  * See the License for the specific language governing permissions and
00014  * limitations under the License.
00015  */
00016 #ifndef M2M_CONNECTION_HANDLER_H__
00017 #define M2M_CONNECTION_HANDLER_H__
00018 
00019 #include "mbed-client/m2mconnectionobserver.h"
00020 #include "mbed-client/m2mconfig.h"
00021 #include "mbed-client/m2minterface.h"
00022 #include "nsdl-c/sn_nsdl.h"
00023 
00024 class M2MConnectionSecurity;
00025 class M2MConnectionHandlerPimpl;
00026 
00027 /**
00028  * @brief M2MConnectionHandler.
00029  * This class handles the socket connection for the LWM2M Client.
00030  */
00031 
00032 class M2MConnectionHandler {
00033 public:
00034 
00035     /**
00036      * @enum ConnectionError
00037      * This enum defines an error that can come from
00038      * socket read and write operation.
00039      */
00040     typedef enum {
00041         CONNECTION_ERROR_WANTS_READ = -1000,
00042         CONNECTION_ERROR_WANTS_WRITE = -1001
00043     }ConnectionError;
00044 
00045 public:
00046 
00047     /**
00048     * @brief Constructor
00049     */
00050     M2MConnectionHandler(M2MConnectionObserver &observer,
00051                          M2MConnectionSecurity* sec,
00052                          M2MInterface::BindingMode mode,
00053                          M2MInterface::NetworkStack stack);
00054 
00055     /**
00056     * @brief Destructor
00057     */
00058     ~M2MConnectionHandler();
00059 
00060     /**
00061     * @brief This binds the socket connection.
00062     * @param listen_port Port to be listened to for an incoming connection.
00063     * @return True if successful, else false.
00064     */
00065     bool bind_connection(const uint16_t listen_port);
00066 
00067     /**
00068     * @brief This resolves the server address. Output is
00069     * returned through a callback.
00070     * @param String Server address.
00071     * @param uint16_t Server port.
00072     * @param ServerType, Server Type to be resolved.
00073     * @param security, M2MSecurity object that determines what
00074     * type of secure connection will be used by the socket.
00075     * @return True if address is valid, else false.
00076     */
00077     bool resolve_server_address(const String& server_address,
00078                                 const uint16_t server_port,
00079                                 M2MConnectionObserver::ServerType server_type,
00080                                 const M2MSecurity* security);
00081 
00082     /**
00083     * @brief Sends data to the connected server.
00084     * @param data_ptr, Data to be sent.
00085     * @param data_len, Length of data to be sent.
00086     * @param address_ptr, Address structure where data has to be sent.
00087     * @return True if data is sent successfully, else false.
00088     */
00089     bool send_data(uint8_t *data_ptr,
00090                            uint16_t data_len,
00091                            sn_nsdl_addr_s *address_ptr);
00092 
00093     /**
00094     * @brief Listens to the incoming data from a remote server.
00095     * @return True if successful, else false.
00096     */
00097     bool start_listening_for_data();
00098 
00099     /**
00100     * @brief Stops listening to the incoming data.
00101     */
00102     void stop_listening();
00103 
00104     /**
00105      * @brief sendToSocket Sends directly to socket. This is used by
00106      * security classes to send the data after it has been encrypted.
00107      * @param buf Buffer to send.
00108      * @param len Length of a buffer.
00109      * @return Number of bytes sent or -1 if failed.
00110      */
00111     int send_to_socket(const unsigned char *buf, size_t len);
00112 
00113     /**
00114      * @brief receiveFromSocket Receives directly from a socket. This
00115      * is used by the security classes to receive raw data to be decrypted.
00116      * @param buf Buffer to send.
00117      * @param len Length of a buffer.
00118      * @return Number of bytes read or -1 if failed.
00119      */
00120     int receive_from_socket(unsigned char *buf, size_t len);
00121 
00122     /**
00123     * @brief Closes the open connection.
00124     */
00125     void close_connection();
00126 
00127     /**
00128     * @brief Error handling for DTLS connectivity.
00129     * @param error, Error code from TLS library
00130     */
00131     void handle_connection_error(int error);
00132 
00133 private:
00134 
00135     M2MConnectionObserver                       &_observer;
00136     M2MConnectionHandlerPimpl                   *_private_impl;
00137 
00138 friend class Test_M2MConnectionHandler;
00139 friend class Test_M2MConnectionHandler_mbed;
00140 friend class Test_M2MConnectionHandler_linux;
00141 friend class M2MConnection_TestObserver;
00142 };
00143 
00144 #endif //M2M_CONNECTION_HANDLER_H__
00145