This repository contains a decoder and verifier for EU Digital COVID Certificate (EUDCC) QR code data, written in Go.

If you got vaccinated and want to know what is stored in the QR code, this package (and example program) can answer that question!

Example usage:

go install github.com/stapelberg/coronaqr/cmd/coronadecode@latest

apt install curl zbar-tools
curl -sL https://github.com/eu-digital-green-certificates/dgc-testdata/raw/main/CH/png/1.png | \
	zbarimg --quiet --raw - | \
	coronadecode

(With older Go versions before 1.16, use go get -u github.com/stapelberg/coronaqr/cmd/coronadecode instead.)

For cryptographic signature 🔐 verification to work, you need to obtain a trust list from somewhere, i.e. a list of certificates that you deem suitable for verification.

The trustlistmirror package implements loading the trust lists of the German, Austrian or French governments, which each include all the certificates that are accepted EU-wide.

This is how you would select which trust list to use:

curl -sL https://github.com/eu-digital-green-certificates/dgc-testdata/raw/main/CH/png/1.png | \
        zbarimg --quiet --raw - | \
        coronadecode -verify -trustlist=trustlistmirror/at

This implementation passes the positive and negative interoperability tests ✅ of multiple countries provided in the https://github.com/eu-digital-green-certificates/dgc-testdata/ repository.