TDLib — readFileRemotePart fork

A focused fork of tdlib/td that adds zero-disk streaming for Kodi addons running on low-storage Android TV boxes and Raspberry Pi.

Streams a byte range directly from Telegram's servers without staging the file to local disk first.

readFileRemotePart file_id:int32 offset:int53 count:int32 = Data;

Standard TDLib requires downloadFile before you can read bytes — that fills the device storage. On a cheap Android TV box with 4–8 GB eMMC (most of it used by Android + apps), a single 1 GB MKV fills the cache. readFileRemotePart lets a media player buffer and seek without writing anything to disk.

When Telegram redirects a large file to a CDN node, the CDN operator could theoretically tamper with the bytes — AES-CTR provides confidentiality but not integrity. This fork fetches upload.getCdnFileHashes from the trusted main DC and SHA-256-verifies every decrypted CDN chunk before delivering it to the caller. Aliaksei Levin (TDLib author) flagged the absence of this check as a security vulnerability in the original PR — it is implemented here.

From Aliaksei's review:

"Files are supposed to be cached by Telegram apps and aren't supposed to be downloaded again and again over network."

TDLib's design contract is: download once, cache locally, read from disk. readFileRemotePart breaks that contract by re-fetching bytes on every seek. For most users on normal hardware this is the wrong trade-off. For storage-constrained embedded devices (Android TV boxes, Raspberry Pi) it is the only viable option — the disk cache would hold at most one file at a time and get evicted constantly anyway.

Download from Releases:

Releases are tagged vVERSION-YYYYMMDD (e.g. v1.8.65-20260701).

plugin.video.yourAddon/
  resources/
    lib/
      libtdjsonjava64.so   ← arm64-v8a (copy from libtdjson-android.zip)
      libtdjsonjava32.so   ← armeabi-v7a

Load with ctypes from your service.py — TDLib's JSON interface works identically to upstream.

Builds run automatically on the production branch via GitHub Actions.
Manual trigger: Actions → Build TDLib → Run workflow.

Inputs:

• Rebase first — pull upstream tdlib/td master before building
• Build Windows / Android / Linux ARM — select targets
• Create release — tag and publish to GitHub Releases

TDLib 1.8.65 — Copyright Aliaksei Levin, Arseny Smirnov.
Distributed under the Boost Software License 1.0.