BUG: The token created by compile_token can not be verified by psatoken.Verify

[caiqs-sys]

I use psa-token v0.0.1 and the master branch of iat-verifier. The token created by compile_token can not be verified by psatoken and got an error message "Error fetching alg";

I checked the code of psatoken.Verify, it first extracts alg of the token. But the token created by compile_token has a null header.

func (p *PSAToken) Verify(pk crypto.PublicKey) error {
        if p.message == nil {
                return errors.New("token does not appear to be signed")
        }

        alg, err := cose.GetAlg(p.message.Headers)
        if err != nil {
                return err
        }

        verifier := cose.Verifier{
                Alg:       alg,
                PublicKey: pk,
        }

        err = p.message.Verify([]byte(""), verifier)
        if err != nil {
                return err
        }

        return nil
}

[kallal79]

Sir @thomas-fossati @yogeshbdeshpande @setrofim @caiqs-sys Requesting assignment to debug compile_token header issue in psatoken.Verify. Can contribute fix or test case.