# udp.cpp

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    00001 /* $Id: udp.cpp 26046 2013-11-22 21:41:19Z 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       if (setsockopt(s->second, SOL_SOCKET, SO_BROADCAST, (char *) &val, sizeof(val)) < 0) {
    00100         DEBUG(net, 1, "[udp] setting broadcast failed with: %i", GET_LAST_ERROR());
    00101       }
    00102     }
    00103 #endif
    00104
    00105     /* Send the buffer */
    00106     int res = sendto(s->second, (const char*)p->buffer, p->size, 0, (const struct sockaddr *)send.GetAddress(), send.GetAddressLength());
    00107     DEBUG(net, 7, "[udp] sendto(%s)", send.GetAddressAsString());
    00108
    00109     /* Check for any errors, but ignore it otherwise */
    00110     if (res == -1) DEBUG(net, 1, "[udp] sendto(%s) failed with: %i", send.GetAddressAsString(), GET_LAST_ERROR());
    00111
    00112     if (!all) break;
    00113   }
    00114 }
    00115
    00119 void NetworkUDPSocketHandler::ReceivePackets()
    00120 {
    00121   for (SocketList::iterator s = this->sockets.Begin(); s != this->sockets.End(); s++) {
    00122     for (int i = 0; i < 1000; i++) { // Do not infinitely loop when DoSing with UDP
    00123       struct sockaddr_storage client_addr;
    00124       memset(&client_addr, 0, sizeof(client_addr));
    00125
    00126       Packet p(this);
    00127       socklen_t client_len = sizeof(client_addr);
    00128
    00129       /* Try to receive anything */
    00130       SetNonBlocking(s->second); // Some OSes seem to lose the non-blocking status of the socket
    00131       int nbytes = recvfrom(s->second, (char*)p.buffer, SEND_MTU, 0, (struct sockaddr *)&client_addr, &client_len);
    00132
    00133       /* Did we get the bytes for the base header of the packet? */
    00134       if (nbytes <= 0) break;    // No data, i.e. no packet
    00135       if (nbytes <= 2) continue; // Invalid data; try next packet
    00136
    00137       NetworkAddress address(client_addr, client_len);
    00138       p.PrepareToRead();
    00139
    00140       /* If the size does not match the packet must be corrupted.
    00141        * Otherwise it will be marked as corrupted later on. */
    00142       if (nbytes != p.size) {
    00143         DEBUG(net, 1, "received a packet with mismatching size from %s", address.GetAddressAsString());
    00144         continue;
    00145       }
    00146
    00147       /* Handle the packet */
    00148       this->HandleUDPPacket(&p, &address);
    00149     }
    00150   }
    00151 }
    00152
    00153
    00159 void NetworkUDPSocketHandler::SendNetworkGameInfo(Packet *p, const NetworkGameInfo *info)
    00160 {
    00161   p->Send_uint8 (NETWORK_GAME_INFO_VERSION);
    00162
    00163   /*
    00164    *              Please observe the order.
    00165    * The parts must be read in the same order as they are sent!
    00166    */
    00167
    00168   /* Update the documentation in udp.h on changes
    00169    * to the NetworkGameInfo wire-protocol! */
    00170
    00171   /* NETWORK_GAME_INFO_VERSION = 4 */
    00172   {
    00173     /* Only send the GRF Identification (GRF_ID and MD5 checksum) of
    00174      * the GRFs that are needed, i.e. the ones that the server has
    00175      * selected in the NewGRF GUI and not the ones that are used due
    00176      * to the fact that they are in [newgrf-static] in openttd.cfg */
    00177     const GRFConfig *c;
    00178     uint count = 0;
    00179
    00180     /* Count number of GRFs to send information about */
    00181     for (c = info->grfconfig; c != NULL; c = c->next) {
    00182       if (!HasBit(c->flags, GCF_STATIC)) count++;
    00183     }
    00184     p->Send_uint8 (count); // Send number of GRFs
    00185
    00186     /* Send actual GRF Identifications */
    00187     for (c = info->grfconfig; c != NULL; c = c->next) {
    00188       if (!HasBit(c->flags, GCF_STATIC)) this->SendGRFIdentifier(p, &c->ident);
    00189     }
    00190   }
    00191
    00192   /* NETWORK_GAME_INFO_VERSION = 3 */
    00193   p->Send_uint32(info->game_date);
    00194   p->Send_uint32(info->start_date);
    00195
    00196   /* NETWORK_GAME_INFO_VERSION = 2 */
    00197   p->Send_uint8 (info->companies_max);
    00198   p->Send_uint8 (info->companies_on);
    00199   p->Send_uint8 (info->spectators_max);
    00200
    00201   /* NETWORK_GAME_INFO_VERSION = 1 */
    00202   p->Send_string(info->server_name);
    00203   p->Send_string(info->server_revision);
    00204   p->Send_uint8 (info->server_lang);
    00205   p->Send_bool  (info->use_password);
    00206   p->Send_uint8 (info->clients_max);
    00207   p->Send_uint8 (info->clients_on);
    00208   p->Send_uint8 (info->spectators_on);
    00209   p->Send_string(info->map_name);
    00210   p->Send_uint16(info->map_width);
    00211   p->Send_uint16(info->map_height);
    00212   p->Send_uint8 (info->map_set);
    00213   p->Send_bool  (info->dedicated);
    00214 }
    00215
    00221 void NetworkUDPSocketHandler::ReceiveNetworkGameInfo(Packet *p, NetworkGameInfo *info)
    00222 {
    00223   static const Date MAX_DATE = ConvertYMDToDate(MAX_YEAR, 11, 31); // December is month 11
    00224
    00225   info->game_info_version = p->Recv_uint8();
    00226
    00227   /*
    00228    *              Please observe the order.
    00229    * The parts must be read in the same order as they are sent!
    00230    */
    00231
    00232   /* Update the documentation in udp.h on changes
    00233    * to the NetworkGameInfo wire-protocol! */
    00234
    00235   switch (info->game_info_version) {
    00236     case 4: {
    00237       GRFConfig **dst = &info->grfconfig;
    00238       uint i;
    00239       uint num_grfs = p->Recv_uint8();
    00240
    00241       /* Broken/bad data. It cannot have that many NewGRFs. */
    00242       if (num_grfs > NETWORK_MAX_GRF_COUNT) return;
    00243
    00244       for (i = 0; i < num_grfs; i++) {
    00245         GRFConfig *c = new GRFConfig();
    00246         this->ReceiveGRFIdentifier(p, &c->ident);
    00247         this->HandleIncomingNetworkGameInfoGRFConfig(c);
    00248
    00249         /* Append GRFConfig to the list */
    00250         *dst = c;
    00251         dst = &c->next;
    00252       }
    00253       /* FALL THROUGH */
    00254     }
    00255     case 3:
    00256       info->game_date      = Clamp(p->Recv_uint32(), 0, MAX_DATE);
    00257       info->start_date     = Clamp(p->Recv_uint32(), 0, MAX_DATE);
    00258       /* FALL THROUGH */
    00259     case 2:
    00260       info->companies_max  = p->Recv_uint8 ();
    00261       info->companies_on   = p->Recv_uint8 ();
    00262       info->spectators_max = p->Recv_uint8 ();
    00263       /* FALL THROUGH */
    00264     case 1:
    00265       p->Recv_string(info->server_name,     sizeof(info->server_name));
    00266       p->Recv_string(info->server_revision, sizeof(info->server_revision));
    00267       info->server_lang    = p->Recv_uint8 ();
    00268       info->use_password   = p->Recv_bool  ();
    00269       info->clients_max    = p->Recv_uint8 ();
    00270       info->clients_on     = p->Recv_uint8 ();
    00271       info->spectators_on  = p->Recv_uint8 ();
    00272       if (info->game_info_version < 3) { // 16 bits dates got scrapped and are read earlier
    00273         info->game_date    = p->Recv_uint16() + DAYS_TILL_ORIGINAL_BASE_YEAR;
    00274         info->start_date   = p->Recv_uint16() + DAYS_TILL_ORIGINAL_BASE_YEAR;
    00275       }
    00276       p->Recv_string(info->map_name, sizeof(info->map_name));
    00277       info->map_width      = p->Recv_uint16();
    00278       info->map_height     = p->Recv_uint16();
    00279       info->map_set        = p->Recv_uint8 ();
    00280       info->dedicated      = p->Recv_bool  ();
    00281
    00282       if (info->server_lang >= NETWORK_NUM_LANGUAGES)  info->server_lang = 0;
    00283       if (info->map_set     >= NETWORK_NUM_LANDSCAPES) info->map_set     = 0;
    00284   }
    00285 }
    00286
    00292 void NetworkUDPSocketHandler::HandleUDPPacket(Packet *p, NetworkAddress *client_addr)
    00293 {
    00294   PacketUDPType type;
    00295
    00296   /* New packet == new client, which has not quit yet */
    00297   this->Reopen();
    00298
    00299   type = (PacketUDPType)p->Recv_uint8();
    00300
    00301   switch (this->HasClientQuit() ? PACKET_UDP_END : type) {
    00302     case PACKET_UDP_CLIENT_FIND_SERVER:   this->Receive_CLIENT_FIND_SERVER(p, client_addr);   break;
    00303     case PACKET_UDP_SERVER_RESPONSE:      this->Receive_SERVER_RESPONSE(p, client_addr);      break;
    00304     case PACKET_UDP_CLIENT_DETAIL_INFO:   this->Receive_CLIENT_DETAIL_INFO(p, client_addr);   break;
    00305     case PACKET_UDP_SERVER_DETAIL_INFO:   this->Receive_SERVER_DETAIL_INFO(p, client_addr);   break;
    00306     case PACKET_UDP_SERVER_REGISTER:      this->Receive_SERVER_REGISTER(p, client_addr);      break;
    00307     case PACKET_UDP_MASTER_ACK_REGISTER:  this->Receive_MASTER_ACK_REGISTER(p, client_addr);  break;
    00308     case PACKET_UDP_CLIENT_GET_LIST:      this->Receive_CLIENT_GET_LIST(p, client_addr);      break;
    00309     case PACKET_UDP_MASTER_RESPONSE_LIST: this->Receive_MASTER_RESPONSE_LIST(p, client_addr); break;
    00310     case PACKET_UDP_SERVER_UNREGISTER:    this->Receive_SERVER_UNREGISTER(p, client_addr);    break;
    00311     case PACKET_UDP_CLIENT_GET_NEWGRFS:   this->Receive_CLIENT_GET_NEWGRFS(p, client_addr);   break;
    00312     case PACKET_UDP_SERVER_NEWGRFS:       this->Receive_SERVER_NEWGRFS(p, client_addr);       break;
    00313     case PACKET_UDP_MASTER_SESSION_KEY:   this->Receive_MASTER_SESSION_KEY(p, client_addr);   break;
    00314
    00315     default:
    00316       if (this->HasClientQuit()) {
    00317         DEBUG(net, 0, "[udp] received invalid packet type %d from %s", type, client_addr->GetAddressAsString());
    00318       } else {
    00319         DEBUG(net, 0, "[udp] received illegal packet from %s", client_addr->GetAddressAsString());
    00320       }
    00321       break;
    00322   }
    00323 }
    00324
    00330 void NetworkUDPSocketHandler::ReceiveInvalidPacket(PacketUDPType type, NetworkAddress *client_addr)
    00331 {
    00332   DEBUG(net, 0, "[udp] received packet type %d on wrong port from %s", type, client_addr->GetAddressAsString());
    00333 }
    00334
    00335 void NetworkUDPSocketHandler::Receive_CLIENT_FIND_SERVER(Packet *p, NetworkAddress *client_addr) { this->ReceiveInvalidPacket(PACKET_UDP_CLIENT_FIND_SERVER, client_addr); }
    00336 void NetworkUDPSocketHandler::Receive_SERVER_RESPONSE(Packet *p, NetworkAddress *client_addr) { this->ReceiveInvalidPacket(PACKET_UDP_SERVER_RESPONSE, client_addr); }
    00337 void NetworkUDPSocketHandler::Receive_CLIENT_DETAIL_INFO(Packet *p, NetworkAddress *client_addr) { this->ReceiveInvalidPacket(PACKET_UDP_CLIENT_DETAIL_INFO, client_addr); }
    00338 void NetworkUDPSocketHandler::Receive_SERVER_DETAIL_INFO(Packet *p, NetworkAddress *client_addr) { this->ReceiveInvalidPacket(PACKET_UDP_SERVER_DETAIL_INFO, client_addr); }
    00339 void NetworkUDPSocketHandler::Receive_SERVER_REGISTER(Packet *p, NetworkAddress *client_addr) { this->ReceiveInvalidPacket(PACKET_UDP_SERVER_REGISTER, client_addr); }
    00340 void NetworkUDPSocketHandler::Receive_MASTER_ACK_REGISTER(Packet *p, NetworkAddress *client_addr) { this->ReceiveInvalidPacket(PACKET_UDP_MASTER_ACK_REGISTER, client_addr); }
    00341 void NetworkUDPSocketHandler::Receive_CLIENT_GET_LIST(Packet *p, NetworkAddress *client_addr) { this->ReceiveInvalidPacket(PACKET_UDP_CLIENT_GET_LIST, client_addr); }
    00342 void NetworkUDPSocketHandler::Receive_MASTER_RESPONSE_LIST(Packet *p, NetworkAddress *client_addr) { this->ReceiveInvalidPacket(PACKET_UDP_MASTER_RESPONSE_LIST, client_addr); }
    00343 void NetworkUDPSocketHandler::Receive_SERVER_UNREGISTER(Packet *p, NetworkAddress *client_addr) { this->ReceiveInvalidPacket(PACKET_UDP_SERVER_UNREGISTER, client_addr); }
    00344 void NetworkUDPSocketHandler::Receive_CLIENT_GET_NEWGRFS(Packet *p, NetworkAddress *client_addr) { this->ReceiveInvalidPacket(PACKET_UDP_CLIENT_GET_NEWGRFS, client_addr); }
    00345 void NetworkUDPSocketHandler::Receive_SERVER_NEWGRFS(Packet *p, NetworkAddress *client_addr) { this->ReceiveInvalidPacket(PACKET_UDP_SERVER_NEWGRFS, client_addr); }
    00346 void NetworkUDPSocketHandler::Receive_MASTER_SESSION_KEY(Packet *p, NetworkAddress *client_addr) { this->ReceiveInvalidPacket(PACKET_UDP_MASTER_SESSION_KEY, client_addr); }
    00347
    00348 #endif /* ENABLE_NETWORK */