diff --git a/unum/vendor/golang.org/x/net/ipv4/packet_go1_9.go b/unum/vendor/golang.org/x/net/ipv4/packet_go1_9.go
new file mode 100644
index 0000000..082c36d
--- /dev/null
+++ b/unum/vendor/golang.org/x/net/ipv4/packet_go1_9.go
@@ -0,0 +1,67 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.9
+
+package ipv4
+
+import (
+	"net"
+
+	"golang.org/x/net/internal/socket"
+)
+
+func (c *packetHandler) readFrom(b []byte) (h *Header, p []byte, cm *ControlMessage, err error) {
+	c.rawOpt.RLock()
+	m := socket.Message{
+		Buffers: [][]byte{b},
+		OOB:     NewControlMessage(c.rawOpt.cflags),
+	}
+	c.rawOpt.RUnlock()
+	if err := c.RecvMsg(&m, 0); err != nil {
+		return nil, nil, nil, &net.OpError{Op: "read", Net: c.IPConn.LocalAddr().Network(), Source: c.IPConn.LocalAddr(), Err: err}
+	}
+	var hs []byte
+	if hs, p, err = slicePacket(b[:m.N]); err != nil {
+		return nil, nil, nil, &net.OpError{Op: "read", Net: c.IPConn.LocalAddr().Network(), Source: c.IPConn.LocalAddr(), Err: err}
+	}
+	if h, err = ParseHeader(hs); err != nil {
+		return nil, nil, nil, &net.OpError{Op: "read", Net: c.IPConn.LocalAddr().Network(), Source: c.IPConn.LocalAddr(), Err: err}
+	}
+	if m.NN > 0 {
+		cm = new(ControlMessage)
+		if err := cm.Parse(m.OOB[:m.NN]); err != nil {
+			return nil, nil, nil, &net.OpError{Op: "read", Net: c.IPConn.LocalAddr().Network(), Source: c.IPConn.LocalAddr(), Err: err}
+		}
+	}
+	if src, ok := m.Addr.(*net.IPAddr); ok && cm != nil {
+		cm.Src = src.IP
+	}
+	return
+}
+
+func (c *packetHandler) writeTo(h *Header, p []byte, cm *ControlMessage) error {
+	m := socket.Message{
+		OOB: cm.Marshal(),
+	}
+	wh, err := h.Marshal()
+	if err != nil {
+		return err
+	}
+	m.Buffers = [][]byte{wh, p}
+	dst := new(net.IPAddr)
+	if cm != nil {
+		if ip := cm.Dst.To4(); ip != nil {
+			dst.IP = ip
+		}
+	}
+	if dst.IP == nil {
+		dst.IP = h.Dst
+	}
+	m.Addr = dst
+	if err := c.SendMsg(&m, 0); err != nil {
+		return &net.OpError{Op: "write", Net: c.IPConn.LocalAddr().Network(), Source: c.IPConn.LocalAddr(), Addr: opAddr(dst), Err: err}
+	}
+	return nil
+}