// Copy request.
	req := *r

	// Save authorization header.
	v4Auth := req.Header.Get(xhttp.Authorization)

	// Parse signature version '4' header.
	signV4Values, errCode := parseSignV4(v4Auth, globalSite.Region(), serviceS3)
	if errCode != ErrNone {
		return cred, "", "", time.Time{}, errCode
	}

	// Payload streaming.
	payload := streamingContentSHA256
	if trailers {