Once - download it once

Forwarding sensitive information (like account credentials) to a customer isn't always easy.

1. Sharing the data via mail or chat as cleartext isn't secure.
2. Sharing the data symmetrically encrypted (e.g. encrypted ZIP) needs the exchange of the shared secret in a secure manner.

In above scenarios we can't be even sure that the information wasn't accessed by an eavesdropper.

To be honest, the only perfect solution is sharing the data asymmetrically encrypted (GPG), but this is beyond the capabilities of most recipients.

How does Once work?

Via Once we share a (hard-to-guess) link with the recipient. The recipient can access that link exactly once (hence the name of the project). After accessing the link, the stored document gets deleted.

In case an eavesdropper was faster accessing the link, the real recipient can't use the link anymore and we can tell that the shared information should be considered as leaked.

Build and Install

For information about how to build and install it from the sources, please checkout the README document about the once-server.

A packaged version of the once-server is available for Debian GNU/Linux from our private Debian "sid" Repo:

wget -O - https://schlittermann.de/keys/gpg/apt.schlittermann.de/2F48BFA2AEB951E9370D3599F2E97DC20A805F65.asc | apt-keys add
echo deb http://apt.schlittermann.de/ sid main >> /etc/apt/sources.list.d/schlittermann.list
apt update
apt install once-server/sid

There are more instructions on how to proceed after install.