/* =========================================================================== Copyright (C) 1999-2005 Id Software, Inc. This file is part of Quake III Arena source code. Quake III Arena source code 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; either version 2 of the License, or (at your option) any later version. Quake III Arena source code 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. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with Quake III Arena source code; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA =========================================================================== */ // sv_client.c -- server code for dealing with clients #include "server.h" #include "../qcommon/vm_local.h" static void SV_CloseDownload( client_t* cl ); // pull specific info from a newly changed userinfo string into a more C friendly form static void SV_UserinfoChanged( client_t *cl ) { int i; const char* val; Q_strncpyz( cl->name, Info_ValueForKey( cl->userinfo, "name" ), sizeof(cl->name) ); val = Info_ValueForKey( cl->userinfo, "rate" ); if (val[0]) { cl->rate = Com_ClampInt( 4000, 99999, atoi(val) ); } else { cl->rate = 25000; } val = Info_ValueForKey( cl->userinfo, "snaps" ); if (val[0]) { i = Com_ClampInt( 10, sv_fps->integer, atoi(val) ); } else { i = sv_fps->integer; } cl->snapshotMsec = 1000 / i; // if the client is on the same subnet as the server and we aren't running an // internet public server, assume they don't need a rate choke if ( Sys_IsLANAddress( cl->netchan.remoteAddress ) && sv_lanForceRate->integer && (com_dedicated->integer != 2) ) { cl->rate = 99999; cl->snapshotMsec = 1000 / sv_fps->integer; } // maintain the IP information // this is set in SV_DirectConnect (directly on the server, not transmitted), may be lost when client updates its userinfo // the banning code relies on this being consistently present val = Info_ValueForKey (cl->userinfo, "ip"); if (!val[0]) { //Com_DPrintf("Maintain IP in userinfo for '%s'\n", cl->name); if ( !NET_IsLocalAddress(cl->netchan.remoteAddress) ) Info_SetValueForKey( cl->userinfo, "ip", NET_AdrToString( cl->netchan.remoteAddress ) ); else // force the "ip" info key to "localhost" for local clients Info_SetValueForKey( cl->userinfo, "ip", "localhost" ); } } /* ================= SV_GetChallenge A "getchallenge" OOB command has been received Returns a challenge number that can be used in a subsequent connectResponse command. We do this to prevent denial of service attacks that flood the server with invalid connection IPs. With a challenge, they must give a valid IP address. If we are authorizing, a challenge request will cause a packet to be sent to the authorize server. When an authorizeip is returned, a challenge response will be sent to that ip. ================= */ void SV_GetChallenge( netadr_t from ) { int i; int oldest; int oldestTime; challenge_t *challenge; // ignore if we are in single player if (Cvar_VariableValue("sv_singlePlayer")) return; oldest = 0; oldestTime = 0x7fffffff; // see if we already have a challenge for this ip challenge = &svs.challenges[0]; for (i = 0 ; i < MAX_CHALLENGES ; i++, challenge++) { if ( !challenge->connected && NET_CompareAdr( from, challenge->adr ) ) { break; } if ( challenge->time < oldestTime ) { oldestTime = challenge->time; oldest = i; } } if (i == MAX_CHALLENGES) { // this is the first time this client has asked for a challenge challenge = &svs.challenges[oldest]; challenge->challenge = ( (rand() << 16) ^ rand() ) ^ svs.time; challenge->adr = from; challenge->firstTime = svs.time; challenge->time = svs.time; challenge->connected = qfalse; i = oldest; } // if they are on a lan address, send the challengeResponse immediately if ( Sys_IsLANAddress( from ) ) { challenge->pingTime = svs.time; NET_OutOfBandPrint( NS_SERVER, from, "challengeResponse %i", challenge->challenge ); return; } // look up the authorize server's IP if ( !svs.authorizeAddress.ip[0] && svs.authorizeAddress.type != NA_BAD ) { Com_Printf( "Resolving %s\n", AUTHORIZE_SERVER_NAME ); if ( !NET_StringToAdr( AUTHORIZE_SERVER_NAME, &svs.authorizeAddress ) ) { Com_Printf( "Couldn't resolve address\n" ); return; } svs.authorizeAddress.port = BigShort( PORT_AUTHORIZE ); Com_Printf( "%s resolved to %i.%i.%i.%i:%i\n", AUTHORIZE_SERVER_NAME, svs.authorizeAddress.ip[0], svs.authorizeAddress.ip[1], svs.authorizeAddress.ip[2], svs.authorizeAddress.ip[3], BigShort( svs.authorizeAddress.port ) ); } // if they have been challenging for a long time and we // haven't heard anything from the authorize server, go ahead and // let them in, assuming the id server is down if ( svs.time - challenge->firstTime > AUTHORIZE_TIMEOUT ) { Com_DPrintf( "authorize server timed out\n" ); challenge->pingTime = svs.time; NET_OutOfBandPrint( NS_SERVER, challenge->adr, "challengeResponse %i", challenge->challenge ); return; } // otherwise send their ip to the authorize server if ( svs.authorizeAddress.type != NA_BAD ) { Com_DPrintf( "sending getIpAuthorize for %s\n", NET_AdrToString( from ) ); char game[MAX_QPATH]; const cvar_t* fs = Cvar_Get( "fs_game", "", CVAR_INIT|CVAR_SYSTEMINFO ); if (fs && fs->string[0]) Q_strncpyz( game, fs->string, sizeof(game) ); else Q_strncpyz( game, BASEGAME, sizeof(game) ); // the 0 is for backwards compatibility with obsolete sv_allowanonymous flags // getIpAuthorize 0 NET_OutOfBandPrint( NS_SERVER, svs.authorizeAddress, "getIpAuthorize %i %i.%i.%i.%i %s 0 %s", svs.challenges[i].challenge, from.ip[0], from.ip[1], from.ip[2], from.ip[3], game, sv_strictAuth->string ); } } /* A packet has been returned from the authorize server. If we have a challenge adr for that ip, send the challengeResponse to it */ void SV_AuthorizeIpPacket( netadr_t from ) { int i; if ( !NET_CompareBaseAdr( from, svs.authorizeAddress ) ) { Com_Printf( "SV_AuthorizeIpPacket: not from authorize server\n" ); return; } int challenge = atoi( Cmd_Argv( 1 ) ); for ( i = 0; i < MAX_CHALLENGES; ++i ) { if ( svs.challenges[i].challenge == challenge ) { break; } } if ( i == MAX_CHALLENGES ) { Com_Printf( "SV_AuthorizeIpPacket: challenge not found\n" ); return; } // send a packet back to the original client svs.challenges[i].pingTime = svs.time; const char* s = Cmd_Argv( 2 ); const char* r = Cmd_Argv( 3 ); // reason if ( !Q_stricmp( s, "accept" ) ) { NET_OutOfBandPrint( NS_SERVER, svs.challenges[i].adr, "challengeResponse %i", svs.challenges[i].challenge ); return; } if ( !Q_stricmp( s, "unknown" ) ) { if (!r) { NET_OutOfBandPrint( NS_SERVER, svs.challenges[i].adr, "print\nAwaiting CD key authorization\n" ); } else { NET_OutOfBandPrint( NS_SERVER, svs.challenges[i].adr, "print\n%s\n", r ); } // clear the challenge record so it won't timeout and let them through Com_Memset( &svs.challenges[i], 0, sizeof( svs.challenges[i] ) ); return; } // authorization failed if (!r) { NET_OutOfBandPrint( NS_SERVER, svs.challenges[i].adr, "print\nSomeone is using this CD Key\n" ); } else { NET_OutOfBandPrint( NS_SERVER, svs.challenges[i].adr, "print\n%s\n", r ); } // clear the challenge record so it won't timeout and let them through Com_Memset( &svs.challenges[i], 0, sizeof( svs.challenges[i] ) ); } /* ================== SV_DirectConnect A "connect" OOB command has been received ================== */ void SV_DirectConnect( netadr_t from ) { char userinfo[MAX_INFO_STRING]; int i; client_t *cl, *newcl; client_t temp; sharedEntity_t *ent; int clientNum; int version; int qport; int challenge; int startIndex; int count; char k[MAX_INFO_KEY], v[MAX_INFO_VALUE]; // Cgg Com_DPrintf ("SVC_DirectConnect ()\n"); // Cgg - prevent bypassing server bans through infostring overflow const char* c = Cmd_Argv(1); userinfo[0] = 0; if (!NET_IsLocalAddress(from)) { Info_SetValueForKey(userinfo, "ip", NET_AdrToString(from)); } else { Info_SetValueForKey(userinfo, "ip", "localhost"); } while (*c) { Info_NextPair(&c, k, v); if (!Q_stricmp(k, "ip")) continue; Info_SetValueForKey(userinfo, k, v); } // Q_strncpyz( userinfo, Cmd_Argv(1), sizeof(userinfo) ); // !Cgg version = atoi( Info_ValueForKey( userinfo, "protocol" ) ); if ( version != PROTOCOL_VERSION ) { NET_OutOfBandPrint( NS_SERVER, from, "print\nServer uses protocol version %i.\n", PROTOCOL_VERSION ); Com_DPrintf (" rejected connect from version %i\n", version); return; } challenge = atoi( Info_ValueForKey( userinfo, "challenge" ) ); qport = atoi( Info_ValueForKey( userinfo, "qport" ) ); // quick reject for (i=0,cl=svs.clients ; i < sv_maxclients->integer ; i++,cl++) { if ( cl->state == CS_FREE ) { continue; } if ( NET_CompareBaseAdr( from, cl->netchan.remoteAddress ) && ( cl->netchan.qport == qport || from.port == cl->netchan.remoteAddress.port ) ) { if (( svs.time - cl->lastConnectTime) < (sv_reconnectlimit->integer * 1000)) { Com_DPrintf ("%s:reconnect rejected : too soon\n", NET_AdrToString (from)); return; } break; } } // see if the challenge is valid (LAN clients don't need to challenge) if ( !NET_IsLocalAddress (from) ) { int ping; for (i=0 ; ivalue && ping < sv_minPing->value ) { // don't let them keep trying until they get a big delay NET_OutOfBandPrint( NS_SERVER, from, "print\nServer is for high pings only\n" ); Com_DPrintf ("Client %i rejected on a too low ping\n", i); // reset the address otherwise their ping will keep increasing // with each connect message and they'd eventually be able to connect svs.challenges[i].adr.port = 0; return; } if ( sv_maxPing->value && ping > sv_maxPing->value ) { NET_OutOfBandPrint( NS_SERVER, from, "print\nServer is for low pings only\n" ); Com_DPrintf ("Client %i rejected on a too high ping\n", i); return; } } } else { // Cgg - see above // force the "ip" info key to "localhost" // Info_SetValueForKey( userinfo, "ip", "localhost" ); // !Cgg } newcl = &temp; Com_Memset (newcl, 0, sizeof(client_t)); // if there is already a slot for this ip, reuse it for (i=0,cl=svs.clients ; i < sv_maxclients->integer ; i++,cl++) { if ( cl->state == CS_FREE ) { continue; } if ( NET_CompareBaseAdr( from, cl->netchan.remoteAddress ) && ( cl->netchan.qport == qport || from.port == cl->netchan.remoteAddress.port ) ) { Com_Printf ("%s:reconnect\n", NET_AdrToString (from)); newcl = cl; // this doesn't work because it nukes the players userinfo // // disconnect the client from the game first so any flags the // // player might have are dropped // VM_Call( gvm, GAME_CLIENT_DISCONNECT, newcl - svs.clients ); // goto gotnewcl; } } // find a client slot // if "sv_privateClients" is set > 0, then that number // of client slots will be reserved for connections that // have "password" set to the value of "sv_privatePassword" // Info requests will report the maxclients as if the private // slots didn't exist, to prevent people from trying to connect // to a full server. // This is to allow us to reserve a couple slots here on our // servers so we can play without having to kick people. // check for privateClient password if ( !strcmp( Info_ValueForKey( userinfo, "password" ), sv_privatePassword->string ) ) { startIndex = 0; } else { // skip past the reserved slots startIndex = sv_privateClients->integer; } newcl = NULL; for ( i = startIndex; i < sv_maxclients->integer ; i++ ) { cl = &svs.clients[i]; if (cl->state == CS_FREE) { newcl = cl; break; } } if ( !newcl ) { if ( NET_IsLocalAddress( from ) ) { count = 0; for ( i = startIndex; i < sv_maxclients->integer ; i++ ) { cl = &svs.clients[i]; if (cl->netchan.remoteAddress.type == NA_BOT) { count++; } } // if they're all bots if (count >= sv_maxclients->integer - startIndex) { SV_DropClient(&svs.clients[sv_maxclients->integer - 1], "only bots on server"); newcl = &svs.clients[sv_maxclients->integer - 1]; } else { Com_Error( ERR_FATAL, "server is full on local connect\n" ); return; } } else { NET_OutOfBandPrint( NS_SERVER, from, "print\nServer is full.\n" ); Com_DPrintf ("Rejected a connection.\n"); return; } } // we got a newcl, so reset the reliableSequence and reliableAcknowledge cl->reliableAcknowledge = 0; cl->reliableSequence = 0; gotnewcl: // build a new connection // accept the new client // this is the only place a client_t is ever initialized *newcl = temp; clientNum = newcl - svs.clients; ent = SV_GentityNum( clientNum ); newcl->gentity = ent; // save the challenge newcl->challenge = challenge; // save the address Netchan_Setup( NS_SERVER, &newcl->netchan , from, qport ); // init the netchan queue newcl->netchan_end_queue = &newcl->netchan_start_queue; // save the userinfo Q_strncpyz( newcl->userinfo, userinfo, sizeof(newcl->userinfo) ); // give the game a chance to reject this connection or modify the userinfo intptr_t denied = VM_Call( gvm, GAME_CLIENT_CONNECT, clientNum, qtrue, qfalse ); // firstTime = qtrue if ( denied ) { // we can't just use VM_ArgPtr, because that is only valid inside a VM_Call const char* s = (const char*)VM_ExplicitArgPtr( gvm, denied ); NET_OutOfBandPrint( NS_SERVER, from, "print\n%s\n", s ); Com_DPrintf( "Game rejected a connection: %s.\n", s ); return; } SV_UserinfoChanged( newcl ); // send the connect packet to the client NET_OutOfBandPrint( NS_SERVER, from, "connectResponse" ); Com_DPrintf( "Going from CS_FREE to CS_CONNECTED for %s\n", newcl->name ); newcl->state = CS_CONNECTED; newcl->nextSnapshotTime = svs.time; newcl->lastPacketTime = svs.time; newcl->lastConnectTime = svs.time; // when we receive the first packet from the client, we will // notice that it is from a different serverid and that the // gamestate message was not just sent, forcing a retransmit newcl->gamestateMessageNum = -1; // if this was the first client on the server, or the last client // the server can hold, send a heartbeat to the master. count = 0; for (i=0,cl=svs.clients ; i < sv_maxclients->integer ; i++,cl++) { if ( svs.clients[i].state >= CS_CONNECTED ) { count++; } } if ( count == 1 || count == sv_maxclients->integer ) { SV_Heartbeat_f(); } } // called when the player is totally leaving the server, willingly or not // this is NOT called if the entire server is shutting down: SV_FinalMessage() will handle that void SV_DropClient( client_t* drop, const char* reason ) { int i; if ( drop->state == CS_ZOMBIE ) return; // already dropped if (drop->netchan.remoteAddress.type != NA_BOT) { // see if we already have a challenge for this ip challenge_t* challenge = &svs.challenges[0]; for ( i = 0; i < MAX_CHALLENGES; ++i, ++challenge ) { if ( NET_CompareAdr( drop->netchan.remoteAddress, challenge->adr ) ) { challenge->connected = qfalse; break; } } } // kill any download SV_CloseDownload( drop ); // tell everyone why they got dropped SV_SendServerCommand( NULL, "print \"%s" S_COLOR_WHITE " %s\n\"", drop->name, reason ); Com_DPrintf( "Going to CS_ZOMBIE for %s\n", drop->name ); drop->state = CS_ZOMBIE; // become free in a few seconds if (drop->download) { FS_FCloseFile( drop->download ); drop->download = 0; } // call the prog function for removing a client // this will remove the body, among other things VM_Call( gvm, GAME_CLIENT_DISCONNECT, drop - svs.clients ); // add the disconnect command SV_SendServerCommand( drop, "disconnect \"%s\"", reason ); if ( drop->netchan.remoteAddress.type == NA_BOT ) { SV_BotFreeClient( drop - svs.clients ); } // nuke user info SV_SetUserinfo( drop - svs.clients, "" ); // if this was the last client on the server // force a heartbeat to the master so it is known the server is empty for ( i = 0; i < sv_maxclients->integer; ++i ) { if ( svs.clients[i].state >= CS_CONNECTED ) { break; } } if ( i == sv_maxclients->integer ) { SV_Heartbeat_f(); } } /* ================ SV_SendClientGameState Sends the first message from the server to a connected client. This will be sent on the initial connection and upon each new map load. It will be resent if the client acknowledges a later message but has the wrong gamestate. ================ */ static void SV_SendClientGameState( client_t* client ) { int i; msg_t msg; byte msgBuffer[MAX_MSGLEN]; Com_DPrintf( "SV_SendClientGameState() for %s\n", client->name ); Com_DPrintf( "Going from CS_CONNECTED to CS_PRIMED for %s\n", client->name ); client->state = CS_PRIMED; client->pureAuthentic = qfalse; client->pureReceived = qfalse; // when we receive the first packet from the client, we will // notice that it is from a different serverid and that the // gamestate message was not just sent, forcing a retransmit client->gamestateMessageNum = client->netchan.outgoingSequence; MSG_Init( &msg, msgBuffer, sizeof( msgBuffer ) ); // NOTE, MRE: all server->client messages now acknowledge // let the client know which reliable clientCommands we have received MSG_WriteLong( &msg, client->lastClientCommand ); // send any server commands waiting to be sent first. // we have to do this cause we send the client->reliableSequence // with a gamestate and it sets the clc.serverCommandSequence at // the client side SV_UpdateServerCommandsToClient( client, &msg ); // send the gamestate MSG_WriteByte( &msg, svc_gamestate ); MSG_WriteLong( &msg, client->reliableSequence ); // write the configstrings for ( i = 0; i < MAX_CONFIGSTRINGS; ++i ) { if (sv.configstrings[i][0]) { MSG_WriteByte( &msg, svc_configstring ); MSG_WriteShort( &msg, i ); MSG_WriteBigString( &msg, sv.configstrings[i] ); } } // write the entity baselines entityState_t nullstate; Com_Memset( &nullstate, 0, sizeof( nullstate ) ); for ( i = 0; i < MAX_GENTITIES; ++i ) { const entityState_t* base = &sv.svEntities[i].baseline; if ( !base->number ) continue; MSG_WriteByte( &msg, svc_baseline ); MSG_WriteDeltaEntity( &msg, &nullstate, base, qtrue ); } MSG_WriteByte( &msg, svc_EOF ); MSG_WriteLong( &msg, client - svs.clients ); MSG_WriteLong( &msg, sv.checksumFeed ); if ( msg.overflowed ) { Com_Printf( "ERROR: gamestate message buffer overflow\n" ); } SV_SendMessageToClient( &msg, client ); } void SV_ClientEnterWorld( client_t* cl, const usercmd_t* cmd ) { Com_DPrintf( "Going from CS_PRIMED to CS_ACTIVE for %s\n", cl->name ); cl->state = CS_ACTIVE; // set up the entity for the client int clientNum = cl - svs.clients; sharedEntity_t* ent = SV_GentityNum( clientNum ); ent->s.number = clientNum; cl->gentity = ent; cl->deltaMessage = -1; cl->nextSnapshotTime = svs.time; // generate a snapshot immediately cl->lastUsercmd = *cmd; // tell the game vm that the client is live VM_Call( gvm, GAME_CLIENT_BEGIN, cl - svs.clients ); } /* ============================================================ CLIENT COMMAND EXECUTION ============================================================ */ /////////////////////////////////////////////////////////////// // a download has either aborted or finished, so clean up static void SV_CloseDownload( client_t* cl ) { int i; if (cl->download) { FS_FCloseFile( cl->download ); } cl->download = 0; *cl->downloadName = 0; // free the temporary buffer space for (i = 0; i < MAX_DOWNLOAD_WINDOW; i++) { if (cl->downloadBlocks[i]) { Z_Free( cl->downloadBlocks[i] ); cl->downloadBlocks[i] = NULL; } } } // abort a download if in progress static void SV_StopDownload_f( client_t* cl ) { if (*cl->downloadName) Com_DPrintf( "clientDownload: %d : file \"%s\" aborted\n", cl - svs.clients, cl->downloadName ); SV_CloseDownload( cl ); } // all downloads are finished static void SV_DoneDownload_f( client_t* cl ) { Com_DPrintf( "clientDownload: %s Done\n", cl->name ); // resend the game state to update any clients that entered during the download SV_SendClientGameState( cl ); } // argv[1] will be the last acknowledged block from the client // it should be the same as cl->downloadClientBlock static void SV_NextDownload_f( client_t* cl ) { int block = atoi( Cmd_Argv(1) ); if (block == cl->downloadClientBlock) { Com_DPrintf( "clientDownload: %d : client acknowledge of block %d\n", cl - svs.clients, block ); // Find out if we are done. A zero-length block indicates EOF if (cl->downloadBlockSize[cl->downloadClientBlock % MAX_DOWNLOAD_WINDOW] == 0) { Com_Printf( "clientDownload: %d : file \"%s\" completed\n", cl - svs.clients, cl->downloadName ); SV_CloseDownload( cl ); return; } cl->downloadSendTime = svs.time; cl->downloadClientBlock++; return; } // the acknowledge was for the wrong block: drop the client // FIXME: this is bad... the client will never parse the disconnect message // because the cgame isn't loaded yet SV_DropClient( cl, "broken download" ); } // argv[1] is the file the client wants static void SV_BeginDownload_f( client_t* cl ) { // kill any existing download SV_CloseDownload( cl ); // set cl->downloadName: SV_WriteDownloadToClient will see this and handle the startup Q_strncpyz( cl->downloadName, Cmd_Argv(1), sizeof(cl->downloadName) ); } /* ================== SV_WriteDownloadToClient Check to see if the client wants a file, open it if needed and start pumping the client Fill up msg with data ================== */ void SV_WriteDownloadToClient( client_t *cl , msg_t *msg ) { int curindex; int rate; int blockspersnap; int idPack = 0, missionPack = 0, unreferenced = 1; char errorMessage[1024]; char pakbuf[MAX_QPATH], *pakptr; int numRefPaks; if (!*cl->downloadName) return; // Nothing being downloaded if (!cl->download) { // Chop off filename extension. Com_sprintf(pakbuf, sizeof(pakbuf), "%s", cl->downloadName); pakptr = Q_strrchr(pakbuf, '.'); if(pakptr) { *pakptr = '\0'; // Check for pk3 filename extension if(!Q_stricmp(pakptr + 1, "pk3")) { const char *referencedPaks = FS_ReferencedPakNames(); // Check whether the file appears in the list of referenced // paks to prevent downloading of arbitrary files. Cmd_TokenizeStringIgnoreQuotes(referencedPaks); numRefPaks = Cmd_Argc(); for(curindex = 0; curindex < numRefPaks; curindex++) { if(!FS_FilenameCompare(Cmd_Argv(curindex), pakbuf)) { unreferenced = 0; // now that we know the file is referenced, // check whether it's legal to download it. missionPack = FS_idPak(pakbuf, "missionpack"); idPack = missionPack || FS_idPak(pakbuf, BASEGAME); break; } } } } // We open the file here if ( !sv_allowDownload->integer || idPack || unreferenced || ( cl->downloadSize = FS_SV_FOpenFileRead( cl->downloadName, &cl->download ) ) <= 0 ) { // cannot auto-download file if(unreferenced) { Com_Printf("clientDownload: %d : \"%s\" is not referenced and cannot be downloaded.\n", cl - svs.clients, cl->downloadName); Com_sprintf(errorMessage, sizeof(errorMessage), "File \"%s\" is not referenced and cannot be downloaded.", cl->downloadName); } else if (idPack) { Com_Printf("clientDownload: %d : \"%s\" cannot download id pk3 files\n", cl - svs.clients, cl->downloadName); if (missionPack) { Com_sprintf(errorMessage, sizeof(errorMessage), "Cannot autodownload Team Arena file \"%s\"\n" "The Team Arena mission pack can be found in your local game store.", cl->downloadName); } else { Com_sprintf(errorMessage, sizeof(errorMessage), "Cannot autodownload id pk3 file \"%s\"", cl->downloadName); } } else if ( !sv_allowDownload->integer ) { Com_Printf("clientDownload: %d : \"%s\" download disabled", cl - svs.clients, cl->downloadName); if (sv_pure->integer) { Com_sprintf(errorMessage, sizeof(errorMessage), "Could not download \"%s\" because autodownloading is disabled on the server.\n\n" "You will need to get this file elsewhere before you " "can connect to this pure server.\n", cl->downloadName); } else { Com_sprintf(errorMessage, sizeof(errorMessage), "Could not download \"%s\" because autodownloading is disabled on the server.\n\n" "The server you are connecting to is not a pure server, " "set autodownload to No in your settings and you might be " "able to join the game anyway.\n", cl->downloadName); } } else { // NOTE TTimo this is NOT supposed to happen unless bug in our filesystem scheme? // if the pk3 is referenced, it must have been found somewhere in the filesystem Com_Printf("clientDownload: %d : \"%s\" file not found on server\n", cl - svs.clients, cl->downloadName); Com_sprintf(errorMessage, sizeof(errorMessage), "File \"%s\" not found on server for autodownloading.\n", cl->downloadName); } MSG_WriteByte( msg, svc_download ); MSG_WriteShort( msg, 0 ); // client is expecting block zero MSG_WriteLong( msg, -1 ); // illegal file size MSG_WriteString( msg, errorMessage ); *cl->downloadName = 0; return; } Com_Printf( "clientDownload: %d : beginning \"%s\"\n", cl - svs.clients, cl->downloadName ); cl->downloadCurrentBlock = cl->downloadClientBlock = cl->downloadXmitBlock = 0; cl->downloadCount = 0; cl->downloadEOF = qfalse; } // Perform any reads that we need to while (cl->downloadCurrentBlock - cl->downloadClientBlock < MAX_DOWNLOAD_WINDOW && cl->downloadSize != cl->downloadCount) { curindex = (cl->downloadCurrentBlock % MAX_DOWNLOAD_WINDOW); if (!cl->downloadBlocks[curindex]) cl->downloadBlocks[curindex] = (byte*)Z_Malloc( MAX_DOWNLOAD_BLKSIZE ); cl->downloadBlockSize[curindex] = FS_Read( cl->downloadBlocks[curindex], MAX_DOWNLOAD_BLKSIZE, cl->download ); if (cl->downloadBlockSize[curindex] < 0) { // EOF right now cl->downloadCount = cl->downloadSize; break; } cl->downloadCount += cl->downloadBlockSize[curindex]; // Load in next block cl->downloadCurrentBlock++; } // Check to see if we have eof condition and add the EOF block if (cl->downloadCount == cl->downloadSize && !cl->downloadEOF && cl->downloadCurrentBlock - cl->downloadClientBlock < MAX_DOWNLOAD_WINDOW) { cl->downloadBlockSize[cl->downloadCurrentBlock % MAX_DOWNLOAD_WINDOW] = 0; cl->downloadCurrentBlock++; cl->downloadEOF = qtrue; // We have added the EOF block } // Loop up to window size times based on how many blocks we can fit in the // client snapMsec and rate // based on the rate, how many bytes can we fit in the snapMsec time of the client // normal rate / snapshotMsec calculation rate = cl->rate; if ( sv_maxRate->integer ) { if ( sv_maxRate->integer < 1000 ) { Cvar_Set( "sv_MaxRate", "1000" ); } if ( sv_maxRate->integer < rate ) { rate = sv_maxRate->integer; } } if ( sv_minRate->integer ) { if ( sv_minRate->integer < 1000 ) Cvar_Set( "sv_minRate", "1000" ); if ( sv_minRate->integer > rate ) rate = sv_minRate->integer; } if (!rate) { blockspersnap = 1; } else { blockspersnap = ( (rate * cl->snapshotMsec) / 1000 + MAX_DOWNLOAD_BLKSIZE ) / MAX_DOWNLOAD_BLKSIZE; } if (blockspersnap < 0) blockspersnap = 1; while (blockspersnap--) { // Write out the next section of the file, if we have already reached our window, // automatically start retransmitting if (cl->downloadClientBlock == cl->downloadCurrentBlock) return; // Nothing to transmit if (cl->downloadXmitBlock == cl->downloadCurrentBlock) { // We have transmitted the complete window, should we start resending? //FIXME: This uses a hardcoded one second timeout for lost blocks //the timeout should be based on client rate somehow if (svs.time - cl->downloadSendTime > 1000) cl->downloadXmitBlock = cl->downloadClientBlock; else return; } // Send current block curindex = (cl->downloadXmitBlock % MAX_DOWNLOAD_WINDOW); MSG_WriteByte( msg, svc_download ); MSG_WriteShort( msg, cl->downloadXmitBlock ); // block zero is special, contains file size if ( cl->downloadXmitBlock == 0 ) MSG_WriteLong( msg, cl->downloadSize ); MSG_WriteShort( msg, cl->downloadBlockSize[curindex] ); // Write the block if ( cl->downloadBlockSize[curindex] ) { MSG_WriteData( msg, cl->downloadBlocks[curindex], cl->downloadBlockSize[curindex] ); } Com_DPrintf( "clientDownload: %d : writing block %d\n", cl - svs.clients, cl->downloadXmitBlock ); // Move on to the next block // It will get sent with next snap shot. The rate will keep us in line. cl->downloadXmitBlock++; cl->downloadSendTime = svs.time; } } /////////////////////////////////////////////////////////////// // the client is going to disconnect, so remove the connection immediately static void SV_Disconnect_f( client_t* cl ) { SV_DropClient( cl, "disconnected" ); } /* If we are pure, disconnect the client if they do not meet the following conditions: the first two checksums match our view of cgame and ui there are no additional checksums that we do not have */ static void SV_VerifyPaks_f( client_t* cl ) { int i, j, checksum; int nCurArg = 1; // we know arg0 is "cp" const char* pArg; const char* paks; int nClientChkSum[MAX_PAKFILES]; int nServerChkSum[MAX_PAKFILES]; int nServerPaks; if (!sv_pure->integer) return; // must be at least 6 args: "cp serverid cgame ui @ [pak [...]] numChecksums" int nClientPaks = Cmd_Argc() - 6; if (nClientPaks < 0) { goto impure; } pArg = Cmd_Argv(nCurArg++); // https://zerowing.idsoftware.com/bugzilla/show_bug.cgi?id=475 // we may get incoming cp sequences from a previous checksumFeed, which we need to ignore // since serverId is a frame count, it always goes up if (atoi(pArg) < sv.checksumFeedServerId) { Com_DPrintf("ignoring outdated cp command from client %s\n", cl->name); return; // but don't flag them as impure } cl->pureReceived = qtrue; // we "expect" the client to load certain things from certain pk3 files // namely the ui and cgame that we think they should have pArg = Cmd_Argv(nCurArg++); if ( !FS_FileIsInPAK("vm/cgame.qvm", &checksum, NULL) || !pArg || *pArg == '@' || atoi(pArg) != checksum ) goto impure; pArg = Cmd_Argv(nCurArg++); if ( !FS_FileIsInPAK("vm/ui.qvm", &checksum, NULL) || !pArg || *pArg == '@' || atoi(pArg) != checksum ) goto impure; // should be sitting at the delimiter now pArg = Cmd_Argv(nCurArg++); if (*pArg != '@') goto impure; // grab all the checksums and make sure they're unique // so the client can't just send the same checksum 5 times // KHB note that this is incorrect, since there could be legit collisions // which would make the server unusable, but... for (i = 0; i < nClientPaks; ++i) { nClientChkSum[i] = atoi(Cmd_Argv(nCurArg++)); for (j = 0; j < i; ++j) { if (nClientChkSum[j] == nClientChkSum[i]) { goto impure; } } } // save numChecksums since we need that too nClientChkSum[i] = atoi(Cmd_Argv(nCurArg++)); // get the pure checksums of the pk3 files loaded by the server paks = FS_LoadedPakPureChecksums(); Cmd_TokenizeString( paks ); nServerPaks = min( MAX_PAKFILES, Cmd_Argc() ); for (i = 0; i < nServerPaks; ++i) { nServerChkSum[i] = atoi(Cmd_Argv(i)); } // see if the client has provided any checksums of pk3 files not loaded by the server for (i = 0; i < nClientPaks; ++i) { for (j = 0; j < nServerPaks; ++j) { if (nClientChkSum[i] == nServerChkSum[j]) { break; } } if (j >= nServerPaks) { goto impure; } } // check if the number of checksums was correct checksum = sv.checksumFeed; for (i = 0; i < nClientPaks; ++i) { checksum ^= nClientChkSum[i]; } checksum ^= nClientPaks; if (checksum != nClientChkSum[nClientPaks]) goto impure; cl->pureAuthentic = qtrue; return; impure: cl->pureAuthentic = qfalse; cl->nextSnapshotTime = -1; cl->state = CS_ACTIVE; SV_SendClientSnapshot( cl ); SV_DropClient( cl, "Unpure client detected. Invalid .PK3 files referenced!" ); } static void SV_ResetPureClient_f( client_t* cl ) { cl->pureAuthentic = qfalse; cl->pureReceived = qfalse; } static void SV_UpdateUserinfo_f( client_t* cl ) { Q_strncpyz( cl->userinfo, Cmd_Argv(1), sizeof(cl->userinfo) ); SV_UserinfoChanged( cl ); // call prog code to allow overrides VM_Call( gvm, GAME_CLIENT_USERINFO_CHANGED, cl - svs.clients ); } typedef struct { const char* name; void (*func)( client_t* cl ); } clientcmd_t; static const clientcmd_t clcmds[] = { { "userinfo", SV_UpdateUserinfo_f }, { "disconnect", SV_Disconnect_f }, { "cp", SV_VerifyPaks_f }, { "vdr", SV_ResetPureClient_f }, { "download", SV_BeginDownload_f }, { "nextdl", SV_NextDownload_f }, { "stopdl", SV_StopDownload_f }, { "donedl", SV_DoneDownload_f }, { NULL, NULL } }; // also called by bot code void SV_ExecuteClientCommand( client_t* cl, const char* s, qbool clientOK ) { Cmd_TokenizeString( s ); // see if it is a server level command for ( const clientcmd_t* cmd = clcmds; cmd->name; ++cmd ) { if (!strcmp( Cmd_Argv(0), cmd->name ) ) { cmd->func( cl ); return; } } if (clientOK) { // pass unknown strings to the game if (sv.state == SS_GAME) { VM_Call( gvm, GAME_CLIENT_COMMAND, cl - svs.clients ); return; } } Com_DPrintf( "client text ignored for %s: %s\n", cl->name, Cmd_Argv(0) ); } static qbool SV_ClientCommand( client_t* cl, msg_t* msg ) { int seq = MSG_ReadLong( msg ); const char* s = MSG_ReadString( msg ); // see if we have already executed it if ( cl->lastClientCommand >= seq ) return qtrue; Com_DPrintf( "clientCommand: %s : %i : %s\n", cl->name, seq, s ); // drop the connection if we have somehow lost commands if ( seq > cl->lastClientCommand + 1 ) { Com_Printf( "Client %s lost %i clientCommands\n", cl->name, seq - cl->lastClientCommand + 1 ); SV_DropClient( cl, "Lost reliable commands" ); return qfalse; } // malicious users may try using too many string commands // to lag other players. If we decide that we want to stall // the command, we will stop processing the rest of the packet, // including the usercmd. This causes flooders to lag themselves // but not other people // We don't do this when the client hasn't been active yet since its // normal to spam a lot of commands when downloading qbool clientOk = qtrue; if ( !com_cl_running->integer && sv_floodProtect->integer && (cl->state >= CS_ACTIVE) ) { if (cl->nextReliableTime > svs.time) { clientOk = qfalse; } else { // don't allow another command for one second cl->nextReliableTime = svs.time + 1000; } } SV_ExecuteClientCommand( cl, s, clientOk ); cl->lastClientCommand = seq; Com_sprintf( cl->lastClientCommandString, sizeof(cl->lastClientCommandString), "%s", s ); return qtrue; // continue procesing } /////////////////////////////////////////////////////////////// // can also be called indirectly by the vm (used for bots) void SV_ClientThink( client_t* cl, const usercmd_t* cmd ) { cl->lastUsercmd = *cmd; if ( cl->state != CS_ACTIVE ) { return; // may have been kicked during the last usercmd } VM_Call( gvm, GAME_CLIENT_THINK, cl - svs.clients ); } /* ================== SV_UserMove The message usually contains all the movement commands that were in the last three packets, so that the information in dropped packets can be recovered. On very fast clients, there may be multiple usercmd packed into each of the backup packets. ================== */ static void SV_UserMove( client_t *cl, msg_t *msg, qbool delta ) { if ( delta ) { cl->deltaMessage = cl->messageAcknowledge; } else { cl->deltaMessage = -1; } int cmdCount = MSG_ReadByte( msg ); if ( cmdCount < 1 ) { Com_Printf( "cmdCount < 1\n" ); return; } if ( cmdCount > MAX_PACKET_USERCMDS ) { Com_Printf( "cmdCount > MAX_PACKET_USERCMDS\n" ); return; } // use the checksum feed in the key int key = sv.checksumFeed; // also use the message acknowledge key ^= cl->messageAcknowledge; // also use the last acknowledged server command in the key key ^= Com_HashKey(cl->reliableCommands[ cl->reliableAcknowledge & (MAX_RELIABLE_COMMANDS-1) ], 32); usercmd_t cmds[MAX_PACKET_USERCMDS]; usercmd_t nullcmd; Com_Memset( &nullcmd, 0, sizeof(nullcmd) ); Com_Memset( &cmds, 0, sizeof(cmds) ); usercmd_t *oldcmd = &nullcmd; for (int i = 0; i < cmdCount; ++i ) { usercmd_t *cmd = &cmds[i]; MSG_ReadDeltaUsercmdKey( msg, key, oldcmd, cmd ); oldcmd = cmd; } // save time for ping calculation if this is the first ack of a given snap if ( cl->frames[ cl->messageAcknowledge & PACKET_MASK ].messageAcked <= 0 ) cl->frames[ cl->messageAcknowledge & PACKET_MASK ].messageAcked = Sys_Milliseconds(); // catch the no-cp-yet situation before SV_ClientEnterWorld // if CS_ACTIVE, then it's time to trigger a new gamestate emission // if not, then we are getting remaining parasite usermove commands, which we should ignore if (sv_pure->integer && !cl->pureReceived) { if (cl->state == CS_ACTIVE) { // we didn't get a cp yet, don't assume anything and just send the gamestate all over again Com_DPrintf( "%s: didn't get cp command, resending gamestate\n", cl->name, cl->state ); SV_SendClientGameState( cl ); } return; } // if this is the first usercmd we have received this gamestate, put the client into the world if ( cl->state == CS_PRIMED ) { SV_ClientEnterWorld( cl, &cmds[0] ); // the moves can be processed normally } // a bad cp command was sent, drop the client if (sv_pure->integer && !cl->pureAuthentic) { SV_DropClient( cl, "Cannot validate pure client!" ); return; } if ( cl->state != CS_ACTIVE ) { cl->deltaMessage = -1; return; } // usually, the first couple commands will be duplicates // of ones we have previously received, but the servertimes // in the commands will cause them to be immediately discarded for (int i = 0; i < cmdCount; ++i ) { // if this is a cmd from before a map_restart ignore it if ( cmds[i].serverTime > cmds[cmdCount-1].serverTime ) { continue; } // extremely lagged or cmd from before a map_restart //if ( cmds[i].serverTime > svs.time + 3000 ) { // continue; //} // don't execute if this is an old cmd which is already executed // these old cmds are included when cl_packetdup > 0 if ( cmds[i].serverTime <= cl->lastUsercmd.serverTime ) { continue; } SV_ClientThink( cl, &cmds[i] ); } } /* =========================================================================== USER CMD EXECUTION =========================================================================== */ /* =================== SV_ExecuteClientMessage Parse a client packet =================== */ void SV_ExecuteClientMessage( client_t *cl, msg_t *msg ) { int c; int serverId; MSG_Bitstream(msg); serverId = MSG_ReadLong( msg ); cl->messageAcknowledge = MSG_ReadLong( msg ); if (cl->messageAcknowledge < 0) { // usually only hackers create messages like this // it is more annoying for them to let them hanging #ifndef NDEBUG SV_DropClient( cl, "DEBUG: illegible client message" ); #endif return; } cl->reliableAcknowledge = MSG_ReadLong( msg ); // NOTE: when the client message is fux0red the acknowledgement numbers // can be out of range, this could cause the server to send thousands of server // commands which the server thinks are not yet acknowledged in SV_UpdateServerCommandsToClient if (cl->reliableAcknowledge < cl->reliableSequence - MAX_RELIABLE_COMMANDS) { // usually only hackers create messages like this // it is more annoying for them to let them hanging #ifndef NDEBUG SV_DropClient( cl, "DEBUG: illegible client message" ); #endif cl->reliableAcknowledge = cl->reliableSequence; return; } // if this is a usercmd from a previous gamestate, // ignore it or retransmit the current gamestate // // if the client was downloading, let it stay at whatever serverId and // gamestate it was at. This allows it to keep downloading even when // the gamestate changes. After the download is finished, we'll // notice and send it a new game state // // https://zerowing.idsoftware.com/bugzilla/show_bug.cgi?id=536 // don't drop as long as previous command was a nextdl, after a dl is done, downloadName is set back to "" // but we still need to read the next message to move to next download or send gamestate // I don't like this hack though, it must have been working fine at some point, suspecting the fix is somewhere else if ( serverId != sv.serverId && !*cl->downloadName && !strstr(cl->lastClientCommandString, "nextdl") ) { if ( serverId >= sv.restartedServerId && serverId < sv.serverId ) { // TTimo - use a comparison here to catch multiple map_restart // they just haven't caught the map_restart yet Com_DPrintf("%s : ignoring pre map_restart / outdated client message\n", cl->name); return; } // if we can tell that the client has dropped the last // gamestate we sent them, resend it if ( cl->messageAcknowledge > cl->gamestateMessageNum ) { Com_DPrintf( "%s : dropped gamestate, resending\n", cl->name ); SV_SendClientGameState( cl ); } return; } // this client has acknowledged the new gamestate so it's // safe to start sending it the real time again if ( cl->oldServerTime && serverId == sv.serverId ) { Com_DPrintf( "%s acknowledged gamestate\n", cl->name ); cl->oldServerTime = 0; } // read optional clientCommand strings do { c = MSG_ReadByte( msg ); if ( c == clc_EOF ) { break; } if ( c != clc_clientCommand ) { break; } if ( !SV_ClientCommand( cl, msg ) ) { return; // we couldn't execute it because of the flood protection } if (cl->state == CS_ZOMBIE) { return; // disconnect command } } while ( 1 ); // read the usercmd_t if ( c == clc_move ) { SV_UserMove( cl, msg, qtrue ); } else if ( c == clc_moveNoDelta ) { SV_UserMove( cl, msg, qfalse ); } else if ( c != clc_EOF ) { Com_Printf( "WARNING: bad command byte for client %i\n", cl - svs.clients ); } // if ( msg->readcount != msg->cursize ) { // Com_Printf( "WARNING: Junk at end of packet for client %i\n", cl - svs.clients ); // } }