Add OID doc comments

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

coordinator/oid/oid.go

@@ -4,6 +4,7 @@ import (
 	"encoding/asn1"
 )
 
+// Getter returns an ASN.1 Object Identifier.
 type Getter interface {
 	OID() asn1.ObjectIdentifier
 }
@@ -11,39 +12,51 @@ type Getter interface {
 // Here we define OIDs for different CSPs. Currently this is used in attested TLS to distinguish the attestation documents.
 // OIDs beginning with 1.3.9900 are reserved and can be used without registration.
 
+// Dummy OID for testing.
 type Dummy struct{}
 
+// OID returns the struct's object identifier.
 func (Dummy) OID() asn1.ObjectIdentifier {
 	return asn1.ObjectIdentifier{1, 3, 9900, 1}
 }
 
+// AWS holds the AWS OID.
 type AWS struct{}
 
+// OID returns the struct's object identifier.
 func (AWS) OID() asn1.ObjectIdentifier {
 	return asn1.ObjectIdentifier{1, 3, 9900, 2}
 }
 
+// GCP holds the GCP OID.
 type GCP struct{}
 
+// OID returns the struct's object identifier.
 func (GCP) OID() asn1.ObjectIdentifier {
 	return asn1.ObjectIdentifier{1, 3, 9900, 3}
 }
 
+// Azure holds the Azure OID.
 type Azure struct{}
 
+// OID returns the struct's object identifier.
 func (Azure) OID() asn1.ObjectIdentifier {
 	return asn1.ObjectIdentifier{1, 3, 9900, 4}
 }
 
+// QEMU holds the QEMU OID.
 type QEMU struct{}
 
+// OID returns the struct's object identifier.
 func (QEMU) OID() asn1.ObjectIdentifier {
 	return asn1.ObjectIdentifier{1, 3, 9900, 5}
 }
 
+// GCPNonCVM returns the GCP OID for non CVMs.
 // TODO: Remove once we no longer use non cvms.
 type GCPNonCVM struct{}
 
+// OID returns the struct's object identifier.
 func (GCPNonCVM) OID() asn1.ObjectIdentifier {
 	return asn1.ObjectIdentifier{1, 3, 9900, 99}
 }