src/ptclib/udp.cxx

   1 //
   2 // stund/udp.cxx
   3 //
   4 // Copyright (c) 2002 Alan Hawrylyshen, Jason Fischl
   5 //
   6 // Permission is hereby granted, free of charge, to any person obtaining
   7 // a copy of this software and associated documentation files (the
   8 // "Software"), to deal in the Software without restriction, including
   9 // without limitation the rights to use, copy, modify, merge, publish,
  10 // distribute, sublicense, and/or sell copies of the Software, and to
  11 // permit persons to whom the Software is furnished to do so, subject to
  12 // the following conditions:
  13 //
  14 // The above copyright notice and this permission notice shall be
  15 // included in all copies or substantial portions of the Software.
  16 //
  17 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  18 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  19 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  20 // IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
  21 // CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  22 // TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  23 // SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  24 //
  25 //
  26 // A portion of this code is taken from lbproxy, a part of VOCAL.
  27 //
  28 // http://www.vovida.org/vocal/
  29 //
  30 //
  31
  32 #ifndef _WIN32_WCE
  33 #include <cassert>
  34 #include <cstdio>
  35 #include <cstring>
  36 #include <errno.h>
  37 #include <stdlib.h>
  38 #else
  39 #include <stdlibx.h>
  40 #endif // !_WIN32_WCE
  41 #include <time.h>
  42
  43 #if defined(__GNUC__) && __GNUC__ > 2
  44 #include <iostream>
  45 #else
  46 #include <iostream.h>
  47 #endif
  48
  49 #ifdef WIN32
  50
  51 #ifndef _WIN32_WCE
  52 #include <winsock2.h>
  53 #endif // !_WIN32_WCE
  54
  55 #include <stdlib.h>
  56 #include <io.h>
  57
  58 #else
  59
  60 #include <arpa/inet.h>
  61 #include <stdlib.h>
  62 #include <unistd.h>
  63 #include <fcntl.h>
  64 #include <netinet/in.h>
  65 #include <sys/socket.h>
  66 #include <sys/types.h>
  67 #include <netdb.h>
  68 #include <string.h>
  69 #include <unistd.h>
  70
  71 #endif
  72
  73
  74 #include "string.h"
  75 #include "udp.h"
  76
  77
  78 void
  79 parseHostName( char* peerName,
  80                unsigned int* ip,
  81                unsigned short* portVal,
  82                unsigned int defaultPort )
  83 {
  84    in_addr sin_addr;
  85
  86    char host[512];
  87    strncpy(host,peerName,512);
  88    host[512-1]='\0';
  89    char* port = NULL;
  90
  91    int portNum = defaultPort;
  92
  93    // pull out the port part if present.
  94    char* sep = strchr(host,':');
  95
  96    if ( sep == NULL )
  97    {
  98       portNum = defaultPort;
  99    }
 100    else
 101    {
 102       *sep = '\0';
 103       port = sep + 1;
 104       // set port part
 105
 106       char* endPtr=NULL;
 107
 108       portNum = strtol(port,&endPtr,0);
 109
 110       if ( endPtr != NULL )
 111       {
 112          if ( *endPtr != '\0' )
 113          {
 114             portNum = defaultPort;
 115          }
 116       }
 117    }
 118
 119    assert( portNum >= 1024 );
 120    assert( portNum <= 65000 );
 121
 122
 123
 124    // figure out the host part
 125    struct hostent* h;
 126
 127    h = gethostbyname( host );
 128    if ( h == NULL )
 129    {
 130       *ip = ntohl( 0x7F000001L );
 131    }
 132    else
 133    {
 134       sin_addr = *(struct in_addr*)h->h_addr;
 135       *ip = ntohl( sin_addr.s_addr );
 136    }
 137
 138    *portVal = portNum;
 139 }
 140
 141
 142 Socket
 143 openPort( unsigned short port, unsigned int interfaceIp )
 144 {
 145    Socket fd;
 146
 147    fd = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
 148    if ( fd == INVALID_SOCKET )
 149    {
 150       //int err = errno;
 151       //cerr << "Could not create a UDP socket:" << err << endl;
 152       return INVALID_SOCKET;
 153    }
 154
 155 #if 0
 156    if ( port == 0 )
 157    {
 158       // just use an ephermieal port - no bind
 159       return fd;
 160    }
 161 #endif
 162
 163    struct sockaddr_in addr;
 164    memset((char*) &(addr),0, sizeof((addr)));
 165    addr.sin_family = AF_INET;
 166    addr.sin_addr.s_addr = htonl(INADDR_ANY);
 167    addr.sin_port = htons(port);
 168
 169    if ( (interfaceIp != 0) &&
 170        ( interfaceIp != 0x100007f ) )
 171    {
 172        addr.sin_addr.s_addr = htonl(interfaceIp);
 173    }
 174
 175    if ( bind( fd,(struct sockaddr*)&addr, sizeof(addr)) != 0 )
 176    {
 177       int e = errno;
 178
 179       switch (e)
 180       {
 181          case EADDRINUSE:
 182          {
 183             //cerr << "Port " << port << " for receiving UDP is in use" << endl;
 184             return INVALID_SOCKET;
 185          }
 186          break;
 187          case EADDRNOTAVAIL:
 188          {
 189             //cerr << "Cannot assign requested address" << endl;
 190             return INVALID_SOCKET;
 191          }
 192          break;
 193          default:
 194          {
 195             //cerr << "Could not bind UDP receive port. Error=" << e << endl;
 196             return INVALID_SOCKET;
 197          }
 198          break;
 199       }
 200    }
 201    //clog << "Opened port " << port << " on fd " << fd << endl;
 202
 203    assert( fd != INVALID_SOCKET  );
 204
 205    return fd;
 206 }
 207
 208
 209 bool
 210 getMessage( Socket fd, char* buf, int* len,
 211             unsigned int* srcIp, unsigned short* srcPort )
 212 {
 213     assert( fd != INVALID_SOCKET );
 214
 215    int originalSize = *len;
 216
 217    struct sockaddr_in from;
 218 #if defined(P_MACOSX) || defined (__BEOS__)
 219    int fromLen = sizeof(from);
 220 #else
 221    socklen_t fromLen = sizeof(from);
 222 #endif
 223
 224    *len = recvfrom(fd,
 225                    buf,
 226                    *len,
 227                    0,
 228                    (struct sockaddr *)&from,
 229                    &fromLen);
 230
 231    if ( *len == SOCKET_ERROR )
 232    {
 233         int err = errno;
 234
 235         switch (err)
 236         {
 237         case ENOTSOCK:
 238                 //cerr << "Error fd not a socket" <<   endl;
 239                 break;
 240         default:
 241             ;//cerr << "Error=" << err << endl;
 242         }
 243
 244         return false;
 245    }
 246
 247    if ( *len < 0 )
 248    {
 249      //clog << "socket closed?" << endl;
 250      return false;
 251    }
 252
 253    if ( *len == 0 )
 254    {
 255       //clog << "socket closed?" << endl;
 256       return false;
 257    }
 258
 259    *srcPort = ntohs(from.sin_port);
 260    *srcIp = ntohl(from.sin_addr.s_addr);
 261
 262    if ( (*len)+1 >= originalSize )
 263    {
 264       //cerr << "Received a message that was too large" << endl;
 265       return false;
 266    }
 267    buf[*len]=0;
 268
 269    return true;
 270 }
 271
 272
 273 bool
 274 sendMessage( Socket fd, char* buf, int l,
 275              unsigned int dstIp, unsigned short dstPort )
 276 {
 277    assert( fd != INVALID_SOCKET );
 278
 279    int s;
 280    if ( dstPort == 0 )
 281    {
 282       // sending on a connected port
 283       assert( dstIp == 0 );
 284
 285       s = send(fd,buf,l,0);
 286    }
 287    else
 288    {
 289       assert( dstIp != 0 );
 290       assert( dstPort != 0 );
 291
 292       struct sockaddr_in to;
 293       int toLen = sizeof(to);
 294       memset(&to,0,toLen);
 295
 296      to.sin_family = AF_INET;
 297      to.sin_port = htons(dstPort);
 298       to.sin_addr.s_addr = htonl(dstIp);
 299
 300       s = sendto(fd, buf, l, 0,(sockaddr*)&to, toLen);
 301    }
 302
 303    if ( s == SOCKET_ERROR )
 304    {
 305       int e = errno;
 306       switch (e)
 307       {
 308          case ECONNREFUSED:
 309
 310          #ifndef __BEOS__
 311          case EHOSTDOWN:
 312          #endif
 313
 314          case EHOSTUNREACH:
 315          {
 316             // quietly ignore this
 317          }
 318          break;
 319          case EAFNOSUPPORT:
 320          {
 321             //cerr << "err EAFNOSUPPORT in send" << endl;
 322          }
 323          break;
 324          default:
 325          {
 326             //cerr << "err " << e << " "  << strerror(e) << " in send" << endl;
 327          }
 328       }
 329       return false;
 330    }
 331
 332    if ( s == 0 )
 333    {
 334       //cerr << "no data sent in send" << endl;
 335       return false;
 336    }
 337
 338    if ( s != l )
 339    {
 340       //cerr << "only " << s << " out of " << l << " bytes sent" << endl;
 341       return false;
 342    }
 343
 344    return true;
 345 }
 346
 347
 348 void
 349 initNetwork()
 350 {
 351 #ifdef WIN32
 352    WORD wVersionRequested = MAKEWORD( 2, 2 );
 353    WSADATA wsaData;
 354    int err;
 355
 356    err = WSAStartup( wVersionRequested, &wsaData );
 357    if ( err != 0 )
 358    {
 359       // could not find a usable WinSock DLL
 360       //cerr << "Could not load winsock" << endl;
 361       assert(0); // is this is failing, try a different version that 2.2, 1.0 or later will likely work
 362       exit(1);
 363    }
 364
 365    /* Confirm that the WinSock DLL supports 2.2.*/
 366    /* Note that if the DLL supports versions greater    */
 367    /* than 2.2 in addition to 2.2, it will still return */
 368    /* 2.2 in wVersion since that is the version we      */
 369    /* requested.                                        */
 370
 371    if ( LOBYTE( wsaData.wVersion ) != 2 ||
 372         HIBYTE( wsaData.wVersion ) != 2 )
 373    {
 374       /* Tell the user that we could not find a usable */
 375       /* WinSock DLL.                                  */
 376       WSACleanup( );
 377       //cerr << "Bad winsock verion" << endl;
 378       assert(0); // is this is failing, try a different version that 2.2, 1.0 or later will likely work
 379       exit(1);
 380    }
 381 #endif
 382 }
 383
 384
 385 // Local Variables:
 386 // mode:c++
 387 // c-file-style:"ellemtel"
 388 // c-file-offsets:((case-label . +))
 389 // indent-tabs-mode:nil
 390 // End: