UDPSocket.cpp

00001 /* Copyright (C) 2012 mbed.org, MIT License
00002  *
00003  * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
00004  * and associated documentation files (the "Software"), to deal in the Software without restriction,
00005  * including without limitation the rights to use, copy, modify, merge, publish, distribute,
00006  * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
00007  * furnished to do so, subject to the following conditions:
00008  *
00009  * The above copyright notice and this permission notice shall be included in all copies or
00010  * substantial portions of the Software.
00011  *
00012  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
00013  * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
00014  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
00015  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00016  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
00017  */
00018 
00019 #include "UDPSocket.h"
00020 
00021 static int udp_local_port;
00022 
00023 UDPSocket::UDPSocket()
00024 {
00025 }
00026 
00027 // After init function, bind() should be called.
00028 int UDPSocket::init(void)
00029 {
00030     if (_sock_fd < 0) {
00031         _sock_fd = eth->new_socket();
00032     }
00033     if (eth->setProtocol(_sock_fd, UDP) == false) return -1;
00034     return 0;
00035 }
00036 
00037 // Server initialization
00038 int UDPSocket::bind(int port)
00039 {
00040     if (_sock_fd < 0) {
00041         _sock_fd = eth->new_socket();
00042         if (_sock_fd < 0) {
00043             return -1;
00044         }
00045     }
00046     // set local port
00047     if (port != 0) {
00048         eth->sreg<uint16_t>(_sock_fd, Sn_PORT, port);
00049     } else {
00050         udp_local_port++;
00051         eth->sreg<uint16_t>(_sock_fd, Sn_PORT, udp_local_port);
00052     }
00053     // set udp protocol
00054     eth->setProtocol(_sock_fd, UDP);
00055     eth->scmd(_sock_fd, OPEN);
00056     return 0;
00057 }
00058 
00059 // -1 if unsuccessful, else number of bytes written
00060 int UDPSocket::sendTo(Endpoint &remote, char *packet, int length)
00061 {
00062     int size = eth->wait_writeable(_sock_fd, _blocking ? -1 : _timeout, length-1);
00063     if (size < 0) {
00064         return -1;
00065     }
00066     confEndpoint(remote);
00067     int ret = eth->send(_sock_fd, packet, length);
00068     return ret;
00069 }
00070 
00071 // -1 if unsuccessful, else number of bytes received
00072 int UDPSocket::receiveFrom(Endpoint &remote, char *buffer, int length)
00073 {
00074     uint8_t info[8];
00075     int size = eth->wait_readable(_sock_fd, _blocking ? -1 : _timeout, sizeof(info));
00076     if (size < 0) {
00077         return -1;
00078     }
00079     eth->recv(_sock_fd, (char*)info, sizeof(info));
00080     readEndpoint(remote, info);
00081     int udp_size = info[6]<<8|info[7];
00082     //TEST_ASSERT(udp_size <= (size-sizeof(info)));
00083     if (udp_size > (size-sizeof(info))) {
00084         return -1;
00085     }
00086 
00087     /* Perform Length check here to prevent buffer overrun */
00088     /* fixed by Sean Newton (https://developer.mbed.org/users/SeanNewton/) */
00089     if (udp_size > length) {
00090         //printf("udp_size: %d\n",udp_size);
00091         return -1;
00092     }
00093     return eth->recv(_sock_fd, buffer, udp_size);
00094 }
00095 
00096 void UDPSocket::confEndpoint(Endpoint & ep)
00097 {
00098     char * host = ep.get_address();
00099     // set remote host
00100     eth->sreg_ip(_sock_fd, Sn_DIPR, host);
00101     // set remote port
00102     eth->sreg<uint16_t>(_sock_fd, Sn_DPORT, ep.get_port());
00103 }
00104 
00105 void UDPSocket::readEndpoint(Endpoint & ep, uint8_t info[])
00106 {
00107     char addr[17];
00108     snprintf(addr, sizeof(addr), "%d.%d.%d.%d", info[0], info[1], info[2], info[3]);
00109     uint16_t port = info[4]<<8|info[5];
00110     ep.set_address(addr, port);
00111 }
00112