add vhost for port forwarding

internal/io/io.go

@@ -0,0 +1,15 @@
+package io
+
+import "io"
+
+type readWriter struct {
+	io.Reader
+	io.Writer
+}
+
+func NewReadWriter(r io.Reader, w io.Writer) io.ReadWriter {
+	return &readWriter{
+		Reader: r,
+		Writer: w,
+	}
+}