What is vgca_xeonline?

VGCA XeOnline is an open source tool that lets Linux users digitally sign PDF documents using a physical USB security token, the kind of small hardware device that plugs into a computer to prove your identity for official signatures. It is aimed at people in Vietnam, and likely elsewhere, who need Linux support for digital signing since most signing software of this kind targets Windows. The tool works through a standard called PKCS number eleven, which is a common way for software to talk to security hardware like USB tokens and smart cards. Rather than being just a one off PDF signer, the project is built as a reusable platform: the same core signing engine is meant to eventually plug into desktop apps, web browsers through a Chrome extension, and government digital services, though several of those integrations are still marked as in progress. Currently working features include signing PDFs one at a time or in a batch, stamping a PDF with an image such as a signature graphic, and previewing the signed document before finalizing it. It currently recognizes two brands of USB token, Bit4id and SafeNet, with support for several other Vietnamese certificate authorities still planned. The application has a graphical interface built with Tkinter, a standard Python toolkit for desktop windows and buttons. To run it, you clone the repository, set up a Python virtual environment, install the listed dependencies, and start the program. It has been tested on Linux Mint and Ubuntu. The project is released under the MIT license, meaning it can be used, modified, and redistributed freely, including for commercial purposes, as long as the original copyright notice is kept. Ready to install .deb packages are also offered on the project's GitHub releases page for users who do not want to build it from source.