header:            h,
		bucket:            bucket,
		object:            object,
		customerKeyHeader: h.Get(xhttp.AmzServerSideEncryptionCustomerKey),
		copySource:        copySource,
		metadata:          cloneMSS(oi.UserDefined),
	}

	if w.copySource {
		w.customerKeyHeader = h.Get(xhttp.AmzServerSideEncryptionCopyCustomerKey)
	}

	if err := w.buildDecrypter(w.parts[w.partIndex].Number); err != nil {