# udp.cpp

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    00001 /* $Id: udp.cpp 18809 2010-01-15 16:41:15Z rubidium $ */
    00002
    00003 /*
    00004  * This file is part of OpenTTD.
    00005  * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
    00006  * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
    00007  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
    00008  */
    00009
    00014 #ifdef ENABLE_NETWORK
    00015
    00016 #include "../../stdafx.h"
    00017 #include "../../date_func.h"
    00018 #include "../../debug.h"
    00019 #include "udp.h"
    00020
    00025 NetworkUDPSocketHandler::NetworkUDPSocketHandler(NetworkAddressList *bind)
    00026 {
    00027   if (bind != NULL) {
    00028     for (NetworkAddress *addr = bind->Begin(); addr != bind->End(); addr++) {
    00029       *this->bind.Append() = *addr;
    00030     }
    00031   } else {
    00032     /* As hostname NULL and port 0/NULL don't go well when
    00033      * resolving it we need to add an address for each of
    00034      * the address families we support. */
    00035     *this->bind.Append() = NetworkAddress(NULL, 0, AF_INET);
    00036     *this->bind.Append() = NetworkAddress(NULL, 0, AF_INET6);
    00037   }
    00038 }
    00039
    00040
    00045 bool NetworkUDPSocketHandler::Listen()
    00046 {
    00047   /* Make sure socket is closed */
    00048   this->Close();
    00049
    00050   for (NetworkAddress *addr = this->bind.Begin(); addr != this->bind.End(); addr++) {
    00051     addr->Listen(SOCK_DGRAM, &this->sockets);
    00052   }
    00053
    00054   return this->sockets.Length() != 0;
    00055 }
    00056
    00060 void NetworkUDPSocketHandler::Close()
    00061 {
    00062   for (SocketList::iterator s = this->sockets.Begin(); s != this->sockets.End(); s++) {
    00063     closesocket(s->second);
    00064   }
    00065   this->sockets.Clear();
    00066 }
    00067
    00068 NetworkRecvStatus NetworkUDPSocketHandler::CloseConnection(bool error)
    00069 {
    00070   NetworkSocketHandler::CloseConnection(error);
    00071   return NETWORK_RECV_STATUS_OKAY;
    00072 }
    00073
    00081 void NetworkUDPSocketHandler::SendPacket(Packet *p, NetworkAddress *recv, bool all, bool broadcast)
    00082 {
    00083   if (this->sockets.Length() == 0) this->Listen();
    00084
    00085   for (SocketList::iterator s = this->sockets.Begin(); s != this->sockets.End(); s++) {
    00086     /* Make a local copy because if we resolve it we cannot
    00087      * easily unresolve it so we can resolve it later again. */
    00088     NetworkAddress send(*recv);
    00089
    00090     /* Not the same type */
    00091     if (!send.IsFamily(s->first.GetAddress()->ss_family)) continue;
    00092
    00093     p->PrepareToSend();
    00094
    00095 #ifndef BEOS_NET_SERVER /* will work around this, some day; maybe. */
    00096     if (broadcast) {
    00097       /* Enable broadcast */
    00098       unsigned long val = 1;
    00099       setsockopt(s->second, SOL_SOCKET, SO_BROADCAST, (char *) &val, sizeof(val));
    00100     }
    00101 #endif
    00102
    00103     /* Send the buffer */
    00104     int res = sendto(s->second, (const char*)p->buffer, p->size, 0, (struct sockaddr *)send.GetAddress(), send.GetAddressLength());
    00105     DEBUG(net, 7, "[udp] sendto(%s)", send.GetAddressAsString());
    00106
    00107     /* Check for any errors, but ignore it otherwise */
    00108     if (res == -1) DEBUG(net, 1, "[udp] sendto(%s) failed with: %i", send.GetAddressAsString(), GET_LAST_ERROR());
    00109
    00110     if (!all) break;
    00111   }
    00112 }
    00113
    00117 void NetworkUDPSocketHandler::ReceivePackets()
    00118 {
    00119   for (SocketList::iterator s = this->sockets.Begin(); s != this->sockets.End(); s++) {
    00120     struct sockaddr_storage client_addr;
    00121     memset(&client_addr, 0, sizeof(client_addr));
    00122
    00123     Packet p(this);
    00124     int packet_len = sizeof(p.buffer);
    00125     socklen_t client_len = sizeof(client_addr);
    00126
    00127     /* Try to receive anything */
    00128     SetNonBlocking(s->second); // Some OSes seem to lose the non-blocking status of the socket
    00129     int nbytes = recvfrom(s->second, (char*)p.buffer, packet_len, 0, (struct sockaddr *)&client_addr, &client_len);
    00130
    00131     /* We got some bytes for the base header of the packet. */
    00132     if (nbytes > 2) {
    00133       NetworkAddress address(client_addr, client_len);
    00134       p.PrepareToRead();
    00135
    00136       /* If the size does not match the packet must be corrupted.
    00137        * Otherwise it will be marked as corrupted later on. */
    00138       if (nbytes != p.size) {
    00139         DEBUG(net, 1, "received a packet with mismatching size from %s", address.GetAddressAsString());
    00140         return;
    00141       }
    00142
    00143       /* Handle the packet */
    00144       this->HandleUDPPacket(&p, &address);
    00145     }
    00146   }
    00147 }
    00148
    00149
    00155 void NetworkUDPSocketHandler::Send_NetworkGameInfo(Packet *p, const NetworkGameInfo *info)
    00156 {
    00157   p->Send_uint8 (NETWORK_GAME_INFO_VERSION);
    00158
    00159   /*
    00160    *              Please observe the order.
    00161    * The parts must be read in the same order as they are sent!
    00162    */
    00163
    00164   /* Update the documentation in udp.h on changes
    00165    * to the NetworkGameInfo wire-protocol! */
    00166
    00167   /* NETWORK_GAME_INFO_VERSION = 4 */
    00168   {
    00169     /* Only send the GRF Identification (GRF_ID and MD5 checksum) of
    00170      * the GRFs that are needed, i.e. the ones that the server has
    00171      * selected in the NewGRF GUI and not the ones that are used due
    00172      * to the fact that they are in [newgrf-static] in openttd.cfg */
    00173     const GRFConfig *c;
    00174     uint count = 0;
    00175
    00176     /* Count number of GRFs to send information about */
    00177     for (c = info->grfconfig; c != NULL; c = c->next) {
    00178       if (!HasBit(c->flags, GCF_STATIC)) count++;
    00179     }
    00180     p->Send_uint8 (count); // Send number of GRFs
    00181
    00182     /* Send actual GRF Identifications */
    00183     for (c = info->grfconfig; c != NULL; c = c->next) {
    00184       if (!HasBit(c->flags, GCF_STATIC)) this->Send_GRFIdentifier(p, c);
    00185     }
    00186   }
    00187
    00188   /* NETWORK_GAME_INFO_VERSION = 3 */
    00189   p->Send_uint32(info->game_date);
    00190   p->Send_uint32(info->start_date);
    00191
    00192   /* NETWORK_GAME_INFO_VERSION = 2 */
    00193   p->Send_uint8 (info->companies_max);
    00194   p->Send_uint8 (info->companies_on);
    00195   p->Send_uint8 (info->spectators_max);
    00196
    00197   /* NETWORK_GAME_INFO_VERSION = 1 */
    00198   p->Send_string(info->server_name);
    00199   p->Send_string(info->server_revision);
    00200   p->Send_uint8 (info->server_lang);
    00201   p->Send_bool  (info->use_password);
    00202   p->Send_uint8 (info->clients_max);
    00203   p->Send_uint8 (info->clients_on);
    00204   p->Send_uint8 (info->spectators_on);
    00205   p->Send_string(info->map_name);
    00206   p->Send_uint16(info->map_width);
    00207   p->Send_uint16(info->map_height);
    00208   p->Send_uint8 (info->map_set);
    00209   p->Send_bool  (info->dedicated);
    00210 }
    00211
    00217 void NetworkUDPSocketHandler::Recv_NetworkGameInfo(Packet *p, NetworkGameInfo *info)
    00218 {
    00219   static const Date MAX_DATE = ConvertYMDToDate(MAX_YEAR, 11, 31); // December is month 11
    00220
    00221   info->game_info_version = p->Recv_uint8();
    00222
    00223   /*
    00224    *              Please observe the order.
    00225    * The parts must be read in the same order as they are sent!
    00226    */
    00227
    00228   /* Update the documentation in udp.h on changes
    00229    * to the NetworkGameInfo wire-protocol! */
    00230
    00231   switch (info->game_info_version) {
    00232     case 4: {
    00233       GRFConfig **dst = &info->grfconfig;
    00234       uint i;
    00235       uint num_grfs = p->Recv_uint8();
    00236
    00237       /* Broken/bad data. It cannot have that many NewGRFs. */
    00238       if (num_grfs > NETWORK_MAX_GRF_COUNT) return;
    00239
    00240       for (i = 0; i < num_grfs; i++) {
    00241         GRFConfig *c = CallocT<GRFConfig>(1);
    00242         this->Recv_GRFIdentifier(p, c);
    00243         this->HandleIncomingNetworkGameInfoGRFConfig(c);
    00244
    00245         /* Append GRFConfig to the list */
    00246         *dst = c;
    00247         dst = &c->next;
    00248       }
    00249     } // Fallthrough
    00250     case 3:
    00251       info->game_date      = Clamp(p->Recv_uint32(), 0, MAX_DATE);
    00252       info->start_date     = Clamp(p->Recv_uint32(), 0, MAX_DATE);
    00253       /* Fallthrough */
    00254     case 2:
    00255       info->companies_max  = p->Recv_uint8 ();
    00256       info->companies_on   = p->Recv_uint8 ();
    00257       info->spectators_max = p->Recv_uint8 ();
    00258       /* Fallthrough */
    00259     case 1:
    00260       p->Recv_string(info->server_name,     sizeof(info->server_name));
    00261       p->Recv_string(info->server_revision, sizeof(info->server_revision));
    00262       info->server_lang    = p->Recv_uint8 ();
    00263       info->use_password   = p->Recv_bool  ();
    00264       info->clients_max    = p->Recv_uint8 ();
    00265       info->clients_on     = p->Recv_uint8 ();
    00266       info->spectators_on  = p->Recv_uint8 ();
    00267       if (info->game_info_version < 3) { // 16 bits dates got scrapped and are read earlier
    00268         info->game_date    = p->Recv_uint16() + DAYS_TILL_ORIGINAL_BASE_YEAR;
    00269         info->start_date   = p->Recv_uint16() + DAYS_TILL_ORIGINAL_BASE_YEAR;
    00270       }
    00271       p->Recv_string(info->map_name, sizeof(info->map_name));
    00272       info->map_width      = p->Recv_uint16();
    00273       info->map_height     = p->Recv_uint16();
    00274       info->map_set        = p->Recv_uint8 ();
    00275       info->dedicated      = p->Recv_bool  ();
    00276
    00277       if (info->server_lang >= NETWORK_NUM_LANGUAGES)  info->server_lang = 0;
    00278       if (info->map_set     >= NETWORK_NUM_LANDSCAPES) info->map_set     = 0;
    00279   }
    00280 }
    00281
    00286 #define UDP_COMMAND(type) case type: this->NetworkPacketReceive_ ## type ## _command(p, client_addr); break;
    00287
    00293 void NetworkUDPSocketHandler::HandleUDPPacket(Packet *p, NetworkAddress *client_addr)
    00294 {
    00295   PacketUDPType type;
    00296
    00297   /* New packet == new client, which has not quit yet */
    00298   this->Reopen();
    00299
    00300   type = (PacketUDPType)p->Recv_uint8();
    00301
    00302   switch (this->HasClientQuit() ? PACKET_UDP_END : type) {
    00303     UDP_COMMAND(PACKET_UDP_CLIENT_FIND_SERVER);
    00304     UDP_COMMAND(PACKET_UDP_SERVER_RESPONSE);
    00305     UDP_COMMAND(PACKET_UDP_CLIENT_DETAIL_INFO);
    00306     UDP_COMMAND(PACKET_UDP_SERVER_DETAIL_INFO);
    00307     UDP_COMMAND(PACKET_UDP_SERVER_REGISTER);
    00308     UDP_COMMAND(PACKET_UDP_MASTER_ACK_REGISTER);
    00309     UDP_COMMAND(PACKET_UDP_CLIENT_GET_LIST);
    00310     UDP_COMMAND(PACKET_UDP_MASTER_RESPONSE_LIST);
    00311     UDP_COMMAND(PACKET_UDP_SERVER_UNREGISTER);
    00312     UDP_COMMAND(PACKET_UDP_CLIENT_GET_NEWGRFS);
    00313     UDP_COMMAND(PACKET_UDP_SERVER_NEWGRFS);
    00314     UDP_COMMAND(PACKET_UDP_MASTER_SESSION_KEY);
    00315
    00316     default:
    00317       if (this->HasClientQuit()) {
    00318         DEBUG(net, 0, "[udp] received invalid packet type %d from %s", type, client_addr->GetAddressAsString());
    00319       } else {
    00320         DEBUG(net, 0, "[udp] received illegal packet from %s", client_addr->GetAddressAsString());
    00321       }
    00322       break;
    00323   }
    00324 }
    00325
    00332 #define DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(type) \
    00333 void NetworkUDPSocketHandler::NetworkPacketReceive_## type ##_command(\
    00334     Packet *p, NetworkAddress *client_addr) { \
    00335   DEBUG(net, 0, "[udp] received packet type %d on wrong port from %s", \
    00336       type, client_addr->GetAddressAsString()); \
    00337 }
    00338
    00339 DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(PACKET_UDP_CLIENT_FIND_SERVER);
    00340 DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(PACKET_UDP_SERVER_RESPONSE);
    00341 DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(PACKET_UDP_CLIENT_DETAIL_INFO);
    00342 DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(PACKET_UDP_SERVER_DETAIL_INFO);
    00343 DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(PACKET_UDP_SERVER_REGISTER);
    00344 DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(PACKET_UDP_MASTER_ACK_REGISTER);
    00345 DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(PACKET_UDP_CLIENT_GET_LIST);
    00346 DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(PACKET_UDP_MASTER_RESPONSE_LIST);
    00347 DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(PACKET_UDP_SERVER_UNREGISTER);
    00348 DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(PACKET_UDP_CLIENT_GET_NEWGRFS);
    00349 DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(PACKET_UDP_SERVER_NEWGRFS);
    00350 DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(PACKET_UDP_MASTER_SESSION_KEY);
    00351
    00352 #endif /* ENABLE_NETWORK */