Merge pull request #41 from veraison/impl-fix

Introduce API to get ImplementationID from PSA Evidence

evidence.go

@@ -46,6 +46,17 @@ func (e *Evidence) GetInstanceID() *[]byte {
 	return &instID
 }
 
+// GetImplementationID returns the ImplementationID claim from the
+// PSA token or a nil pointer if no suitable ImplementationID could
+// be located.
+func (e *Evidence) GetImplementationID() *[]byte {
+	implID, err := e.Claims.GetImplID()
+	if err != nil {
+		return nil
+	}
+	return &implID
+}
+
 // FromCOSE extracts the PSA claims wrapped in the supplied CWT. As per spec,
 // the only acceptable security envelope is COSE_Sign1.
 func (e *Evidence) FromCOSE(cwt []byte) error {

evidence_test.go

@@ -226,6 +226,19 @@ func TestEvidence_GetInstanceID_psa_profile_2_ok(t *testing.T) {
 	assert.Equal(t, expected, actual)
 }
 
+func TestEvidence_GetImplementationID_psa_profile_2_ok(t *testing.T) {
+	tv := mustBuildValidP2Claims(t, false)
+
+	evidence := Evidence{}
+	err := evidence.SetClaims(tv)
+	require.NoError(t, err)
+
+	expected := &testImplementationID
+
+	actual := evidence.GetImplementationID()
+	assert.Equal(t, expected, actual)
+}
+
 func TestEvidence_Verify_no_message(t *testing.T) {
 	evidence := Evidence{}
 	var pk crypto.PublicKey