Add qemu vTPM issuer and validator

Signed-off-by: Daniel Weiße <dw@edgeless.systems>

coordinator/attestation/qemu/issuer.go

@@ -0,0 +1,26 @@
+package qemu
+
+import (
+	"io"
+
+	"github.com/edgelesssys/constellation/coordinator/attestation/vtpm"
+	"github.com/edgelesssys/constellation/coordinator/oid"
+	tpmclient "github.com/google/go-tpm-tools/client"
+)
+
+// Issuer for qemu TPM attestation.
+type Issuer struct {
+	oid.QEMU
+	*vtpm.Issuer
+}
+
+// NewIssuer initializes a new Azure Issuer.
+func NewIssuer() *Issuer {
+	return &Issuer{
+		Issuer: vtpm.NewIssuer(
+			vtpm.OpenVTPM,
+			tpmclient.AttestationKeyRSA,
+			func(tpm io.ReadWriteCloser) ([]byte, error) { return nil, nil },
+		),
+	}
+}