如何從DHT中下載torrent文件？

Question

我寫了一個simple script，查找給定info_hash的示例對等IP。我在BEP-0005中看不到這類信息：我如何從DHT中提取torrent文件？

Answer 1

該DHT不服務種子。它只是提供單個信息集的對等列表。 Torrent文件，或者說是不可變的信息字典，由Bittorrent羣集自己提供。

您將不得不部分實施BEP3,BEP10，最後是BEP9以執行元數據交換。另外實施BEP29和BEP11可以提供改善的連接，在小羣檢索元數據時

其次，其可以是有用的，消耗DHT的資源，而不提供任何，或反覆以請求錘擊節點 - 尤其是引導節點 - 被認爲是不好-mannered。如果你打算獲取大量的torrent文件，你應該運行一個DHT節點作爲後臺程序，例如通過Juliusz Chroboczek的dht lib（C）或mine（java）。我的實現還包含元數據檢索服務。 libtorrent也應該提供所有必要的部分來實現相同。

Answer 2

下面是一個base64編碼的.pcap文件，顯示實際中的完整通信（注意最後一個數據包）。將它解碼並在Wireshark中打開將向您顯示完整的流程 - 結合8472答案中列出的BEP，這可以作爲一個例子。

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