// Do not pass client Host header unless requested.
	if !f.PassHost {
		outReq.Host = target.Host
	}

	// TODO: only supports HTTP 1.1 for now.
	outReq.Proto = "HTTP/1.1"
	outReq.ProtoMajor = 1
	outReq.ProtoMinor = 1

	f.rewriter.Rewrite(outReq)

	// Disable closeNotify when method GET for http pipelining
	if outReq.Method == http.MethodGet {