if err != nil {
			encLogIf(GlobalContext, err)
			return
		}
		data = decrypted
	}
	cs := hash.ReadPartCheckSums(data)
	if len(cs) == len(o.Parts) {
		for i := range o.Parts {
			o.Parts[i].Checksums = cs[i]
		}
	}
	return
}

// metadataEncryptFn provides an encryption function for metadata.
// Will return nil, nil if unencrypted.