fix size accounting for encrypted/compressed objects (#9690)

size calculation in crawler was using the real size
of the object instead of its actual size i.e either
a decrypted or uncompressed size.

this is needed to make sure all other accounting
such as bucket quota and mcs UI to display the
correct values.

cmd/object-api-utils.go

@@ -372,17 +372,23 @@ func (o ObjectInfo) IsCompressedOK() (bool, error) {
 	return true, fmt.Errorf("unknown compression scheme: %s", scheme)
 }
 
-// GetActualSize - read the decompressed size from the meta json.
-func (o ObjectInfo) GetActualSize() int64 {
-	metadata := o.UserDefined
-	sizeStr, ok := metadata[ReservedMetadataPrefix+"actual-size"]
-	if ok {
-		size, err := strconv.ParseInt(sizeStr, 10, 64)
-		if err == nil {
-			return size
-		}
+// GetActualSize - returns the actual size of the stored object
+func (o ObjectInfo) GetActualSize() (int64, error) {
+	if crypto.IsEncrypted(o.UserDefined) {
+		return o.DecryptedSize()
 	}
-	return -1
+	if o.IsCompressed() {
+		sizeStr, ok := o.UserDefined[ReservedMetadataPrefix+"actual-size"]
+		if !ok {
+			return -1, errInvalidDecompressedSize
+		}
+		size, err := strconv.ParseInt(sizeStr, 10, 64)
+		if err != nil {
+			return -1, errInvalidDecompressedSize
+		}
+		return size, nil
+	}
+	return o.Size, nil
 }
 
 // Disabling compression for encrypted enabled requests.
@@ -608,9 +614,9 @@ func NewGetObjectReader(rs *HTTPRangeSpec, oi ObjectInfo, opts ObjectOptions, cl
 		}
 	case isCompressed:
 		// Read the decompressed size from the meta.json.
-		actualSize := oi.GetActualSize()
-		if actualSize < 0 {
-			return nil, 0, 0, errInvalidDecompressedSize
+		actualSize, err := oi.GetActualSize()
+		if err != nil {
+			return nil, 0, 0, err
 		}
 		off, length = int64(0), oi.Size
 		decOff, decLength := int64(0), actualSize