1 /** @addtogroup MCD_MCDIMPL_DAEMON_SRV 2 * @{ 3 * @file 4 * 5 * Connection data. 6 * 7 * <!-- Copyright Giesecke & Devrient GmbH 2009 - 2012 --> 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. The name of the author may not be used to endorse or promote 18 * products derived from this software without specific prior 19 * written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS 22 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 23 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY 25 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE 27 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 29 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 30 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 31 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 */ 33 #ifndef NETLINKCONNECTION_H_ 34 #define NETLINKCONNECTION_H_ 35 36 #include <unistd.h> 37 #include <map> 38 #include <exception> 39 #include <inttypes.h> 40 41 #include <sys/types.h> 42 #include <sys/socket.h> 43 #include <sys/un.h> 44 45 #include "Connection.h" 46 #include "CMutex.h" 47 #include "CSemaphore.h" 48 49 /** PID(address) of MC daemon. */ 50 #define MC_DAEMON_PID 0xFFFFFFFF 51 /** Maximum Netlink payload size 52 * TODO: figure out the best value for this */ 53 #define MAX_PAYLOAD 1024 54 55 #define MC_DAEMON_NETLINK 17 56 57 58 class NetlinkConnection; 59 60 /** 61 * Hash function for unique ID of a connection. 62 * 63 * @param pid Connection PID 64 * @param seq Connection sequenceMagic 65 * 66 * @return Unique identifier of the connection 67 */ 68 uint64_t hashConnection(pid_t pid, uint32_t seq); 69 70 /** Netlink connection manager interface. 71 * This inteface has to be implemented by the handling server 72 * to ensure connection will be removed from accounting when destroied. */ 73 class NetlinkConnectionManager 74 { 75 public: 76 virtual ~NetlinkConnectionManager() {}; 77 /** 78 * Retreive connection based on a unique hash. 79 * Search the peer connections hashmap for a hash and return 80 * the associated Connection object 81 * 82 * @param hash The hash to search 83 * @return The NetlinkConnection object if found or NULL if not found 84 */ 85 virtual NetlinkConnection *findConnection( 86 uint64_t hash 87 ) = 0; 88 89 /** 90 * Insert a connection in connection lisst 91 * Insert a new connection in the peer connections list. If there 92 * is already such a connection 93 * it will be overriden! 94 * 95 * @param hash The hash to use 96 * @param connection The connection object to insert 97 */ 98 virtual void insertConnection( 99 uint64_t hash, 100 NetlinkConnection *connection 101 ) = 0; 102 103 /** 104 * Remove a connection from the peer connections 105 * Remove the connection associated with seq from the peer list. 106 * This doesn't actually free the connection object! 107 * If the hash is invalid nothing happens. 108 * 109 * @param hash The hash hash use 110 */ 111 virtual void removeConnection( 112 uint64_t hash 113 ) = 0; 114 }; 115 116 class NetlinkConnection: public Connection 117 { 118 public: 119 pid_t selfPid; /**< Which PID to use to identify when writing data */ 120 pid_t peerPid; /**< Destination PID for sending data */ 121 uint32_t sequenceMagic; /**< Random? magic to match requests/answers */ 122 uint64_t hash; /**< Unique connection ID, see hashConnection */ 123 124 NetlinkConnection( 125 void 126 ); 127 128 /** 129 * Connection main constructor 130 * 131 * @param manager Connection manager pointer. 132 * @param socketDescriptor Socket descriptor to use for writing 133 * @param pid Connection PID 134 * @param seq Connection sequence magic number 135 */ 136 NetlinkConnection( 137 NetlinkConnectionManager *manager, 138 int socketDescriptor, 139 uint32_t pid, 140 uint32_t seq 141 ); 142 143 virtual ~NetlinkConnection( 144 void 145 ); 146 147 /** 148 * Connect to destination. 149 * 150 * @param Destination pointer. 151 * @return true on success. 152 */ 153 virtual bool connect( 154 const char *dest 155 ); 156 157 /** 158 * Read bytes from the connection(compatiblity method). 159 * 160 * @param buffer Pointer to destination buffer. 161 * @param len Number of bytes to read. 162 * @param timeout Timeout in milliseconds(ignored) 163 * @return Number of bytes read. 164 * @return -1 if select() failed (returned -1) 165 * @return -2 if no data available, i.e. timeout 166 */ 167 virtual size_t readData( 168 void *buffer, 169 uint32_t len, 170 int32_t timeout 171 ); 172 173 /** 174 * Read bytes from the connection. 175 * 176 * @param buffer Pointer to destination buffer. 177 * @param len Number of bytes to read. 178 * @return Number of bytes read. 179 */ 180 virtual size_t readData( 181 void *buffer, 182 uint32_t len 183 ); 184 185 /** 186 * Write bytes to the connection. 187 * 188 * @param buffer Pointer to source buffer. 189 * @param len Number of bytes to read. 190 * @return Number of bytes written. 191 */ 192 virtual size_t writeData( 193 void *buffer, 194 uint32_t len 195 ); 196 197 /** 198 * Set the internal data connection. 199 * This method is called by the 200 * 201 * @param nlh Netlink structure pointing to data. 202 */ 203 void handleMessage( 204 struct nlmsghdr *nlh 205 ); 206 207 private: 208 CMutex dataMutex; 209 CSemaphore dataLeft; 210 struct nlmsghdr *dataMsg; /**< Last message received */ 211 uint32_t dataLen; /**< How much connection data is left */ 212 uint8_t *dataStart; /**< Start pointer of remaining data */ 213 NetlinkConnectionManager *manager; /**< Netlink connection manager(eg. NetlinkServer) */ 214 }; 215 216 typedef std::map<uint64_t, NetlinkConnection *> connectionMap_t; 217 218 #endif /* NETLINKCONNECTION_H_ */ 219 220 /** @} */ 221
