node-minecraft-protocol/examples/proxy.js

var mc = require('../');

var states = mc.protocol.states;
function printHelpAndExit(exitCode) {
    console.log("usage: node proxy.js [<options>...] <target_srv> <user> [<password>]");
    console.log("options:");
    console.log("  --dump ID");
    console.log("    print to stdout messages with the specified ID.");
    console.log("  --dump-all");
    console.log("    print to stdout all messages, except those specified with -x.");
    console.log("  -x ID");
    console.log("    do not print messages with this ID.");
    console.log("examples:");
    console.log("  node proxy.js --dump-all -x 0x0 -x 0x3 -x 0x12 -x 0x015 -x 0x16 -x 0x17 -x 0x18 -x 0x19 localhost Player");
    console.log("    print all messages except for some of the most prolific.");

    process.exit(exitCode);
}

if (process.argv.length < 4) {
    console.log("Too few arguments!");
    printHelpAndExit(1);
}

process.argv.forEach(function(val, index, array) {
    if (val == "-h") {
        printHelpAndExit(0);
    }
});

var args = process.argv.slice(2);
var host;
var port = 25565;
var user;
var passwd;

var printAllIds = false;
var printIdWhitelist = {};
var printIdBlacklist = {};
(function() {
    for (var i = 0; i < args.length; i++) {
        var option = args[i];
        if (!/^-/.test(option)) break;
        if (option == "--dump-all") {
            printAllIds = true;
            continue;
        }
        i++;
        var arg = parseInt(args[i]);
        if (isNaN(arg)) printHelpAndExit(1);
        if (option == "--dump") {
            printIdWhitelist[arg] = true;
        } else if (option == "-x") {
            printIdBlacklist[arg] = true;
        } else {
            printHelpAndExit(1);
        }
    }
    if (!(i + 2 <= args.length && args.length <= i + 3)) printHelpAndExit(1);
    host = args[i++];
    user = args[i++];
    passwd = args[i++];
})();

if (host.indexOf(':') != -1) {
    port = host.substring(host.indexOf(':')+1);
    host = host.substring(0, host.indexOf(':'));
}

var srv = mc.createServer({
  'online-mode': false,
  port: 25566
});
srv.on('login', function (client) {
  var addr = client.socket.remoteAddress;
  console.log('Incoming connection', '('+addr+')');
  var endedClient = false;
  var endedTargetClient = false;
  client.on('end', function() {
    endedClient = true;
    console.log('Connection closed by client', '('+addr+')');
    if (!endedTargetClient)
      targetClient.end("End");
  });
  client.on('error', function() {
    endedClient = true;
    console.log('Connection error by client', '('+addr+')');
    if (!endedTargetClient)
      targetClient.end("Error");
  });
  var targetClient = mc.createClient({
    host: host,
    port: port,
    username: user,
    password: passwd,
    'online-mode': passwd != null ? true : false
  });
  var brokenPackets = [/*0x04, 0x2f, 0x30*/];
  client.on('packet', function(packet) {
    if (targetClient.state == states.PLAY && packet.state == states.PLAY) {
      if (shouldDump(packet.id)) {
        console.log("client->server:",
            client.state + ".0x" + packet.id.toString(16) + " :",
            JSON.stringify(packet));
      }
      if (!endedTargetClient)
        targetClient.write(packet.id, packet);
    }
  });
  targetClient.on('packet', function(packet) {
    if (packet.state == states.PLAY && client.state == states.PLAY &&
        brokenPackets.indexOf(packet.id) === -1)
    {
      if (shouldDump(packet.id)) {
        console.log("client<-server:",
            targetClient.state + ".0x" + packet.id.toString(16) + " :",
            (packet.id != 38 ? JSON.stringify(packet) : "Packet too big"));
      }
      if (!endedClient)
        client.write(packet.id, packet);
    }
  });
  var buffertools = require('buffertools');
  targetClient.on('raw', function(buffer, state) {
    if (client.state != states.PLAY || state != states.PLAY)
      return;
    var packetId = mc.protocol.types.varint[0](buffer, 0);
    var packetData = mc.protocol.parsePacketData(buffer, state, false, {"packet": 1}).results;
    var packetBuff = mc.protocol.createPacketBuffer(packetData.id, packetData.state, packetData, true);
    if (buffertools.compare(buffer, packetBuff) != 0)
    {
      console.log("client<-server: Error in packetId " + state + ".0x" + packetId.value.toString(16));
      console.log(buffer.toString('hex'));
      console.log(packetBuff.toString('hex'));
    }
    /*if (client.state == states.PLAY && brokenPackets.indexOf(packetId.value) !== -1)
    {
      console.log(`client<-server: raw packet);
      console.log(packetData);
      if (!endedClient)
        client.writeRaw(buffer);
    }*/
  });
  client.on('raw', function(buffer, state) {
    if (state != states.PLAY || targetClient.state != states.PLAY)
      return;
    var packetId = mc.protocol.types.varint[0](buffer, 0);
    var packetData = mc.protocol.parsePacketData(buffer, state, true, {"packet": 1}).results;
    var packetBuff = mc.protocol.createPacketBuffer(packetData.id, packetData.state, packetData, false);
    if (buffertools.compare(buffer, packetBuff) != 0)
    {
      console.log("client->server: Error in packetId " + state + ".0x" + packetId.value.toString(16));
      console.log(buffer.toString('hex'));
      console.log(packetBuff.toString('hex'));
    }
  });
  targetClient.on('end', function() {
    endedTargetClient = true;
    console.log('Connection closed by server', '('+addr+')');
    if (!endedClient)
      client.end("End");
  });
  targetClient.on('error', function() {
    endedTargetClient = true;
    console.log('Connection error by server', '('+addr+')');
    if (!endedClient)
      client.end("Error");
  });
});

function shouldDump(id) {
  if (printIdBlacklist[id]) return false;
  if (printAllIds) return true;
  if (printIdWhitelist[id]) return true;
  return false;
}