Hi, may I request to add feature/function to extract the QR KID in the protectedHeader from coseByte in dart_cose?

final protectedHeader = items[_CBOR_DATA_PROTECTED_HEADER_INDEX];

var a = Cbor();
a.decodeFromList(coseByte);
List coseElement = a.getDecodedData().first;

final protectedHeader = coseElement[_CBOR_DATA_PROTECTED_HEADER_INDEX];

var b = Cbor();
b.decodeFromList(protectedHeader);
var kid = b.getDecodedData().first;
qrKid = base64Encode(kid[4]);

lib/dart_cose (exporting public files)
lib/src/* (contains all the files for this library)

Knowing which KID was found in the COSE header is useful to identify which of the certificates was used, and thus the corresponding authority or additional information that the application could know about the KID (such as the country, which should match the country of the DGC, whether it was an NHS one or the eHealth one, whether it was revoked etc.).

In cases when the KID was not found in the Map of kid-to-certificates, it is useful to know what the KID in the header was too.

Refer to corresponding pull request which adds the coseKid to the CoseResult: #11

Add a util function to extract the kid from a pem String

Hi Jeroen,

are test certificates also supported? I have troubles with reading test certificates. With qr codes from vaccinated people it works like a charm, but I am not able to read qr codes from tested people.

I get the following error code when reading a qr code from a tested person

CoseErrorCode (CoseErrorCode.key_not_found)

Thanks!

Alex