Title: GSoC 2026 proposal interest: Generalize the Qubes File Converter beyond PDFs

jayantsaxena · March 5, 2026, 8:21pm

Hi everyone @marmarek @Andrew clausen @ Jean-Philippe

I’m interested in applying for the GSoC 2026 project: Generalize the Qubes PDF Converter to Other File Types.

What excites me about this project is simple — Qubes’ DispVM isolation is already a great safety layer, and extending it beyond PDFs to Office documents, audio/video, and spreadsheets would make it useful for a much wider audience without changing the core security model.

I’ve already contributed to qubes-app-linux-pdf-converter — PR #37 fixes the cancel behavior in the GUI dialog, which gave me a solid understanding of the DispVM lifecycle and signal handling in the converter pipeline.

A couple of questions before I finalize the proposal:

Are there specific issues in the repo you’d like me to tackle to demonstrate readiness, or would it make sense to open new issues for gaps I’ve spotted?
Is the preferred design a separate qvm-convert-file entry point, or extending the existing tool?

I will drafted a rough proposal and would appreciate any early feedback on the direction before I submit it formally.

Thanks!

ben-grande · March 6, 2026, 8:37am

Hi, use the qubes-devel for development discussions.

I recommend reading this previous attempt and all discussion in that thread:

github.com/QubesOS/qubes-app-linux-pdf-converter

Add support for more file types + archlinux packaging

master ← neowutran:master

opened 06:13PM - 22 Apr 20 UTC

neowutran

+403 -159

Main "features" of this pull request ======================== - Add more file …type: Support PDF protected by password, and support office files (all files understood by libreoffice, with password protected file support) - Add archlinux packaging Minor improvements ============== - merge the man page with the readme to avoid text duplication (that does not get updated at the same frequency..) - Switch from ImageMagick to GraphicsMagick (it is a fork of ImageMagick, it is theoretically faster, with less features and less bug prone) Things that need improvement / TODO: ================================================================ - ~~How to quickly tests the software while developing it ? I created a new directory called "dev_tools", it contain some safe tests file and a script to automatically convert them.~~ - ~~Fix debian and fedora packaging~~ - ~~In the client script I added a code that read the pdf file to get its size ```wc -c "$INPUT_FILE" | cut -d ' ' -f 1``` I assumed that counting the number of bytes of a file is a operation simple enough to be bug free. This line is part of the changes I did to support password protected file from the GUI (The server script tell the client script "Hey! It need password!" Or "Hey! All fine, it doesn't need password!" depending on that, the GUI prompt a password form. So I needed avoid closing the file descriptor ```exec >&-``` to be able to keep communicating between client and server after the file have been transferred. Didn't found a way to avoid this bytes counting on the file.~~ Why this pull request ================= I found this project https://dangerzone.rocks https://github.com/firstlookmedia/dangerzone https://github.com/firstlookmedia/dangerzone-converter from Micahflee who implemented the idea for non-Qube based system and improved it to support more file type. So trying to implement it back for Qubes, and improving it a bit further to support password protected file and allow some more file type (still only the files supported by libreoffice, but I am way more permissive with mime type check) Tests I did ========= The things in "dev_tools" Tested it on archlinux, with gui and with cli. Didn't tested it on debian/fedora yet I see there is a pull request to re-implement the script from bash to python. So this pull request will require modifications once the bash -> python is done

Password protected PDFs would be a nice start:

github.com/qubesos/qubes-issues

qvm-convert-pdf: support for password-protected PDF files

opened 12:28PM - 24 Jan 26 UTC

Atrate

C: other P: default

[How to file a helpful issue](https://www.qubes-os.org/doc/issue-tracking/) ###… Qubes OS release 4.3 ### Brief summary The qvm-convert-pdf tool cannot handle password-protected PDF files. ### Steps to reproduce 1. Run `qvm-convert-pdf` on a password-protected from view (encrypted) PDF file. ### Expected behavior 1. User gets a pop-up window asking for the password for the PDF. ### Actual behavior ``` $ qvm-convert-pdf pass.pdf Sending file to Disposable VM... pass.pdf...fail error: pass.pdf: Failed to receive page count Total Sanitized Files: 0/1 ```

About where to prompt for a password, Marek said in a comment on the PR above that it should be on the server, because then it doesn’t require changes in the client/server communication. On the issue above, I mentioned about passing the password first hand via command-line, but this wouldn’t cover the context menu of the file managers, which is the only way GUI users interact with this tool. I am not such a fan for having prompt on the server because it would require the server to have GUI.

Don’t get hold up on the method right now, make way for handling password first.

Use a single tool name, I’d say that it shouldn’t be named qvm-convert-pdf, but don’t get hold up in this, it can be sorted later.

It should return non-zero if the MIME type is not supported
It should not be enabled in the context menu (right click) on the file manager if the MIME type is not supported

jayantsaxena · March 6, 2026, 4:59pm

okay