我正在尝试使用 BitTorrent UDP Tracker Protocol 从公共(public) UDP 跟踪器(例如 tracker.publicbt.com 或 tracker.openbittorrent.com)执行 UDP 抓取。 .我的应用程序向跟踪器发送请求 connection_id 并使用该 id 执行抓取。抓取响应是从跟踪器返回的,没有错误表明数据包格式错误,但无论我使用什么 info_hash,我都会返回“0”作为播种者、吸血者和完成者的数量。
我已经彻底检查过数据包的大小是否正确,info_hash 的起始偏移量是否正确,以及数据是否全部正确。据我所知,创建和发送数据包没有问题。这个问题几天来一直没有得到解答,所以我更新并编辑了下面的代码示例,希望有人能提供帮助。
我已将 info_hash 硬编码到以下示例中。当在命令行上运行时,此代码应连接到跟踪器,获取 connection_id,然后在 Ubuntu torrent info_hash 上执行抓取,将各种信息输出到控制台。
connection_id 被分成两部分,因为它是一个 64 位整数。
var dgram = require('dgram'), server = dgram.createSocket("udp4"), connectionIdHigh = 0x417, connectionIdLow = 0x27101980, transactionId, action, trackerHost = "tracker.publicbt.com", trackerPort = 80, infoHash = "", ACTION_CONNECT = 0, ACTION_ANNOUNCE = 1, ACTION_SCRAPE = 2, ACTION_ERROR = 3, sendPacket = function (buf, host, port) { "use strict"; server.send(buf, 0, buf.length, port, host, function(err, bytes) { if (err) { console.log(err.message); } }); }, startConnection = function (host, port) { "use strict"; var buf = new Buffer(16); transactionId = Math.floor((Math.random()*100000)+1); buf.fill(0); buf.writeUInt32BE(connectionIdHigh, 0); buf.writeUInt32BE(connectionIdLow, 4); buf.writeUInt32BE(ACTION_CONNECT, 8); buf.writeUInt32BE(transactionId, 12); sendPacket(buf, host, port); }, scrapeTorrent = function (host, port, hash) { "use strict"; var buf = new Buffer(56), tmp = ''; infoHash = hash; if (!transactionId) { startConnection(host, port); } else { buf.fill(0); buf.writeUInt32BE(connectionIdHigh, 0); buf.writeUInt32BE(connectionIdLow, 4); buf.writeUInt32BE(ACTION_SCRAPE, 8); buf.writeUInt32BE(transactionId, 12); buf.write(infoHash, 16, buf.length); console.log(infoHash); console.log(buf.toString('utf8', 16, buf.length)); // do scrape sendPacket(buf, host, port); transactionId = null; infoHash = null; } }; server.on("message", function (msg, rinfo) { "use strict"; var buf = new Buffer(msg), seeders, completed, leechers; console.log(rinfo); action = buf.readUInt32BE(0, 4); transactionId = buf.readUInt32BE(4, 4); console.log("returned action: " + action); console.log("returned transactionId: " + transactionId); if (action === ACTION_CONNECT) { console.log("connect response"); connectionIdHigh = buf.readUInt32BE(8, 4); connectionIdLow = buf.readUInt32BE(12, 4); scrapeTorrent(trackerHost, trackerPort, infoHash); } else if (action === ACTION_SCRAPE) { console.log("scrape response"); seeders = buf.readUInt32BE(8, 4); completed = buf.readUInt32BE(12, 4); leechers = buf.readUInt32BE(16, 4); console.log(seeders); console.log(completed); console.log(leechers); } else if (action === ACTION_ERROR) { console.log("error response"); } }); server.on("listening", function () { "use strict"; var address = server.address(); console.log("server listening " + address.address + ":" + address.port); }); server.bind(); scrapeTorrent(trackerHost, trackerPort, "335990D615594B9BE409CCFEB95864E24EC702C7");
最佳答案
我终于解决了这个问题,并为没有早点意识到这一点而踢自己。
一个 info_hash 是一个十六进制编码的字符串,所以当它被写入缓冲区时需要设置它的编码。例如:
buf.write(infoHash, 16, buf.length, 'hex');
UDP 跟踪器协议(protocol)没有提到所需的编码,它只是将其描述为一个 20 字节的字符串。希望这个问答可以帮助遇到同样问题的其他人。
关于javascript - node.js 中的 UDP 跟踪器抓取意外返回零,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/16949036/