const Bzip2 = require('compressjs').Bzip2, Core = require('./core'); class Valve extends Core { constructor() { super(); // legacy goldsrc info response -- basically not used by ANYTHING now, // as most (all?) goldsrc servers respond with the source info reponse // delete in a few years if nothing ends up using it anymore this.goldsrcInfo = false; // unfortunately, the split format from goldsrc is still around, but we // can detect that during the query this.goldsrcSplits = false; // some mods require a challenge, but don't provide them in the new format // at all, use the old dedicated challenge query if needed this.legacyChallenge = false; // 2006 engines don't pass packet switching size in split packet header // while all others do, this need is detected automatically this._skipSizeInSplitHeader = false; this._challenge = ''; } async run(state) { if (!this.options.port) this.options.port = 27015; await this.queryInfo(state); await this.queryChallenge(); await this.queryPlayers(state); await this.queryRules(state); await this.cleanup(state); } async queryInfo(state) { this.debugLog("Requesting info ..."); const b = await this.sendPacket( 0x54, false, 'Source Engine Query\0', this.goldsrcInfo ? 0x6D : 0x49, false ); const reader = this.reader(b); if(this.goldsrcInfo) state.raw.address = reader.string(); else state.raw.protocol = reader.uint(1); state.name = reader.string(); state.map = reader.string(); state.raw.folder = reader.string(); state.raw.game = reader.string(); state.raw.steamappid = reader.uint(2); state.raw.numplayers = reader.uint(1); state.maxplayers = reader.uint(1); if(this.goldsrcInfo) state.raw.protocol = reader.uint(1); else state.raw.numbots = reader.uint(1); state.raw.listentype = reader.uint(1); state.raw.environment = reader.uint(1); if(!this.goldsrcInfo) { state.raw.listentype = String.fromCharCode(state.raw.listentype); state.raw.environment = String.fromCharCode(state.raw.environment); } state.password = !!reader.uint(1); if(this.goldsrcInfo) { state.raw.ismod = reader.uint(1); if(state.raw.ismod) { state.raw.modlink = reader.string(); state.raw.moddownload = reader.string(); reader.skip(1); state.raw.modversion = reader.uint(4); state.raw.modsize = reader.uint(4); state.raw.modtype = reader.uint(1); state.raw.moddll = reader.uint(1); } } state.raw.secure = reader.uint(1); if(this.goldsrcInfo) { state.raw.numbots = reader.uint(1); } else { if(state.raw.folder === 'ship') { state.raw.shipmode = reader.uint(1); state.raw.shipwitnesses = reader.uint(1); state.raw.shipduration = reader.uint(1); } state.raw.version = reader.string(); const extraFlag = reader.uint(1); if(extraFlag & 0x80) state.gamePort = reader.uint(2); if(extraFlag & 0x10) state.raw.steamid = reader.uint(8); if(extraFlag & 0x40) { state.raw.sourcetvport = reader.uint(2); state.raw.sourcetvname = reader.string(); } if(extraFlag & 0x20) state.raw.tags = reader.string(); if(extraFlag & 0x01) state.raw.gameid = reader.uint(8); } // from https://developer.valvesoftware.com/wiki/Server_queries if( state.raw.protocol === 7 && ( state.raw.steamappid === 215 || state.raw.steamappid === 17550 || state.raw.steamappid === 17700 || state.raw.steamappid === 240 ) ) { this._skipSizeInSplitHeader = true; } this.debugLog("STEAM APPID: "+state.raw.steamappid); this.debugLog("PROTOCOL: "+state.raw.protocol); if(state.raw.protocol === 48) { this.debugLog("GOLDSRC DETECTED - USING MODIFIED SPLIT FORMAT"); this.goldsrcSplits = true; } } async queryChallenge() { if(this.legacyChallenge) { // sendPacket will catch the response packet and // save the challenge for us this.debugLog("Requesting legacy challenge key ..."); await this.sendPacket( 0x57, false, null, 0x41, false ); } } async queryPlayers(state) { state.raw.players = []; // CSGO doesn't even respond sometimes if host_players_show is not 2 // Ignore timeouts in only this case const allowTimeout = state.raw.steamappid === 730; this.debugLog("Requesting player list ..."); const b = await this.sendPacket( 0x55, true, null, 0x44, allowTimeout ); if (b === null) return; // timed out const reader = this.reader(b); const num = reader.uint(1); for(let i = 0; i < num; i++) { reader.skip(1); const name = reader.string(); const score = reader.int(4); const time = reader.float(); this.debugLog("Found player: "+name+" "+score+" "+time); // connecting players don't count as players. if(!name) continue; // CSGO sometimes adds a bot named 'Max Players' if host_players_show is not 2 if (state.raw.steamappid === 730 && name === 'Max Players') continue; state.raw.players.push({ name:name, score:score, time:time }); } } async queryRules(state) { state.raw.rules = {}; this.debugLog("Requesting rules ..."); const b = await this.sendPacket(0x56,true,null,0x45,true); if (b === null) return; // timed out - the server probably just has rules disabled const reader = this.reader(b); const num = reader.uint(2); for(let i = 0; i < num; i++) { const key = reader.string(); const value = reader.string(); state.raw.rules[key] = value; } } async cleanup(state) { // Battalion 1944 puts its info into rules fields for some reason if ('bat_name_s' in state.raw.rules) { state.name = state.raw.rules.bat_name_s; delete state.raw.rules.bat_name_s; if ('bat_player_count_s' in state.raw.rules) { state.raw.numplayers = parseInt(state.raw.rules.bat_player_count_s); delete state.raw.rules.bat_player_count_s; } if ('bat_max_players_i' in state.raw.rules) { state.maxplayers = parseInt(state.raw.rules.bat_max_players_i); delete state.raw.rules.bat_max_players_i; } if ('bat_has_password_s' in state.raw.rules) { state.password = state.raw.rules.bat_has_password_s === 'Y'; delete state.raw.rules.bat_has_password_s; } // apparently map is already right, and this var is often wrong delete state.raw.rules.bat_map_s; } // Organize players / hidden players into player / bot arrays const botProbability = (p) => { if (p.time === -1) return Number.MAX_VALUE; return p.time; }; const sortedPlayers = state.raw.players.sort((a,b) => { return botProbability(a) - botProbability(b); }); delete state.raw.players; const numBots = state.raw.numbots; const numPlayers = state.raw.numplayers - numBots; while(state.bots.length < numBots) { if (sortedPlayers.length) state.bots.push(sortedPlayers.pop()); else state.bots.push({}); } while(state.players.length < numPlayers || sortedPlayers.length) { if (sortedPlayers.length) state.players.push(sortedPlayers.pop()); else state.players.push({}); } } /** * Sends a request packet and returns only the response type expected * @param {number} type * @param {boolean} sendChallenge * @param {?string|Buffer} payload * @param {number} expect * @param {boolean=} allowTimeout * @returns Buffer|null **/ async sendPacket( type, sendChallenge, payload, expect, allowTimeout ) { for (let keyRetry = 0; keyRetry < 3; keyRetry++) { let requestKeyChanged = false; const response = await this.sendPacketRaw( type, sendChallenge, payload, (payload) => { const reader = this.reader(payload); const type = reader.uint(1); this.debugLog(() => "Received " + type.toString(16) + " expected " + expect.toString(16)); if (type === 0x41) { const key = reader.uint(4); if (this._challenge !== key) { this.debugLog('Received new challenge key: ' + key); this._challenge = key; if (sendChallenge) { this.debugLog('Challenge key changed -- allowing query retry if needed'); requestKeyChanged = true; } } } if (type === expect) { return reader.rest(); } else if (requestKeyChanged) { return null; } }, () => { if (allowTimeout) return null; } ); if (!requestKeyChanged) { return response; } } throw new Error('Received too many challenge key responses'); } /** * Sends a request packet and assembles partial responses * @param {number} type * @param {boolean} sendChallenge * @param {?string|Buffer} payload * @param {function(Buffer)} onResponse * @param {function()} onTimeout **/ async sendPacketRaw( type, sendChallenge, payload, onResponse, onTimeout ) { if (typeof payload === 'string') payload = Buffer.from(payload, 'binary'); const challengeLength = sendChallenge ? 4 : 0; const payloadLength = payload ? payload.length : 0; const b = Buffer.alloc(5 + challengeLength + payloadLength); b.writeInt32LE(-1, 0); b.writeUInt8(type, 4); if (sendChallenge) { let challenge = this._challenge; if (!challenge) challenge = 0xffffffff; if (this.byteorder === 'le') b.writeUInt32LE(challenge, 5); else b.writeUInt32BE(challenge, 5); } if (payloadLength) payload.copy(b, 5 + challengeLength); const packetStorage = {}; return await this.udpSend( b, (buffer) => { const reader = this.reader(buffer); const header = reader.int(4); if(header === -1) { // full package this.debugLog("Received full packet"); return onResponse(reader.rest()); } if(header === -2) { // partial package const uid = reader.uint(4); if(!(uid in packetStorage)) packetStorage[uid] = {}; const packets = packetStorage[uid]; let bzip = false; if(!this.goldsrcSplits && uid & 0x80000000) bzip = true; let packetNum,payload,numPackets; if(this.goldsrcSplits) { packetNum = reader.uint(1); numPackets = packetNum & 0x0f; packetNum = (packetNum & 0xf0) >> 4; payload = reader.rest(); } else { numPackets = reader.uint(1); packetNum = reader.uint(1); if(!this._skipSizeInSplitHeader) reader.skip(2); if(packetNum === 0 && bzip) reader.skip(8); payload = reader.rest(); } packets[packetNum] = payload; this.debugLog(() => "Received partial packet uid:"+uid+" num:"+packetNum); this.debugLog(() => "Received "+Object.keys(packets).length+'/'+numPackets+" packets for this UID"); if(Object.keys(packets).length !== numPackets) return; // assemble the parts const list = []; for(let i = 0; i < numPackets; i++) { if(!(i in packets)) { throw new Error('Missing packet #'+i); } list.push(packets[i]); } let assembled = Buffer.concat(list); if(bzip) { this.debugLog("BZIP DETECTED - Extracing packet..."); try { assembled = Buffer.from(Bzip2.decompressFile(assembled)); } catch(e) { throw new Error('Invalid bzip packet'); } } const assembledReader = this.reader(assembled); assembledReader.skip(4); // header return onResponse(assembledReader.rest()); } }, onTimeout ); } } module.exports = Valve;