如何从DHT中提取torrent文件？

Question

我写了一个simple script，找出给定info_hash的示例对等IP。我无法在BEP-0005中看到这种信息：我如何从DHT中获取torrent文件？

Answer 1

DHT不提供种子。它只是为各个信息提供对等列表。 Torrent文件，或者更确切地说是不可变信息字典，由bittorrent群本身提供。

您必须部分实施BEP3，BEP10，最后BEP9才能执行元数据交换。另外，实施BEP29和BEP11可以提供改进的连接，这在检索小群组上的元数据时非常有用

其次，消耗DHT的资源而不提供任何或反复锤击节点的请求 - 尤其是引导节点 - 被认为是不礼貌的。如果您打算获取大量torrent文件，则应将DHT节点作为守护程序运行，例如通过Juliusz Chroboczek的dht lib（C）或mine（java）。我的实现还包含元数据检索服务。 libtorrent还应提供实现相同目标的所有必要部分。

Answer 2

这是一个base64编码的.pcap文件，它在实践中显示了完整的通信（注意最后一个数据包）。对它进行解码并在Wireshark中打开将向您显示完整的流程 - 结合8472答案中列出的BEP，这可以作为一个例子。

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