if err != nil {
			writeErrorResponse(ctx, w, toAPIError(ctx, err), r.URL)
			return
		}
		copy(objectEncryptionKey[:], key)

		var nonce [12]byte
		tmp := sha256.Sum256(fmt.Append(nil, uploadID, partID))
		copy(nonce[:], tmp[:12])

		partEncryptionKey := objectEncryptionKey.DerivePartKey(uint32(partID))
		encReader, err := sio.EncryptReader(reader, sio.Config{

	}
	buf, err = madmin.EncryptData(secretKey, buf)
	if err != nil {
		c.Fatalf("unexpected encryption err: %v", err)
	}

	req.ContentLength = int64(len(buf))
	sum := sha256.Sum256(buf)
	req.Header.Set("X-Amz-Content-Sha256", hex.EncodeToString(sum[:]))
	req.Body = io.NopCloser(bytes.NewReader(buf))
	req = signer.SignV4(*req, accessKey, secretKey, "", "")

	// 3.1 Execute the request.

		stringToSign = stringToSign + scope + "\n"
		stringToSign = stringToSign + signature + "\n"
		stringToSign = stringToSign + "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855" + "\n" // hex(sum256(""))
		stringToSign += getSHA256Hash(buffer[:n])

		date := sumHMAC([]byte("AWS4"+secretKey), []byte(currTime.Format(yyyymmdd)))
		region := sumHMAC(date, []byte(regionStr))