diff --git a/unum/vendor/golang.org/x/net/ipv4/endpoint.go b/unum/vendor/golang.org/x/net/ipv4/endpoint.go
new file mode 100644
index 0000000..2ab8773
--- /dev/null
+++ b/unum/vendor/golang.org/x/net/ipv4/endpoint.go
@@ -0,0 +1,187 @@
+// Copyright 2012 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.
+
+package ipv4
+
+import (
+	"net"
+	"syscall"
+	"time"
+
+	"golang.org/x/net/internal/socket"
+)
+
+// BUG(mikio): On Windows, the JoinSourceSpecificGroup,
+// LeaveSourceSpecificGroup, ExcludeSourceSpecificGroup and
+// IncludeSourceSpecificGroup methods of PacketConn and RawConn are
+// not implemented.
+
+// A Conn represents a network endpoint that uses the IPv4 transport.
+// It is used to control basic IP-level socket options such as TOS and
+// TTL.
+type Conn struct {
+	genericOpt
+}
+
+type genericOpt struct {
+	*socket.Conn
+}
+
+func (c *genericOpt) ok() bool { return c != nil && c.Conn != nil }
+
+// NewConn returns a new Conn.
+func NewConn(c net.Conn) *Conn {
+	cc, _ := socket.NewConn(c)
+	return &Conn{
+		genericOpt: genericOpt{Conn: cc},
+	}
+}
+
+// A PacketConn represents a packet network endpoint that uses the
+// IPv4 transport. It is used to control several IP-level socket
+// options including multicasting. It also provides datagram based
+// network I/O methods specific to the IPv4 and higher layer protocols
+// such as UDP.
+type PacketConn struct {
+	genericOpt
+	dgramOpt
+	payloadHandler
+}
+
+type dgramOpt struct {
+	*socket.Conn
+}
+
+func (c *dgramOpt) ok() bool { return c != nil && c.Conn != nil }
+
+// SetControlMessage sets the per packet IP-level socket options.
+func (c *PacketConn) SetControlMessage(cf ControlFlags, on bool) error {
+	if !c.payloadHandler.ok() {
+		return syscall.EINVAL
+	}
+	return setControlMessage(c.dgramOpt.Conn, &c.payloadHandler.rawOpt, cf, on)
+}
+
+// SetDeadline sets the read and write deadlines associated with the
+// endpoint.
+func (c *PacketConn) SetDeadline(t time.Time) error {
+	if !c.payloadHandler.ok() {
+		return syscall.EINVAL
+	}
+	return c.payloadHandler.PacketConn.SetDeadline(t)
+}
+
+// SetReadDeadline sets the read deadline associated with the
+// endpoint.
+func (c *PacketConn) SetReadDeadline(t time.Time) error {
+	if !c.payloadHandler.ok() {
+		return syscall.EINVAL
+	}
+	return c.payloadHandler.PacketConn.SetReadDeadline(t)
+}
+
+// SetWriteDeadline sets the write deadline associated with the
+// endpoint.
+func (c *PacketConn) SetWriteDeadline(t time.Time) error {
+	if !c.payloadHandler.ok() {
+		return syscall.EINVAL
+	}
+	return c.payloadHandler.PacketConn.SetWriteDeadline(t)
+}
+
+// Close closes the endpoint.
+func (c *PacketConn) Close() error {
+	if !c.payloadHandler.ok() {
+		return syscall.EINVAL
+	}
+	return c.payloadHandler.PacketConn.Close()
+}
+
+// NewPacketConn returns a new PacketConn using c as its underlying
+// transport.
+func NewPacketConn(c net.PacketConn) *PacketConn {
+	cc, _ := socket.NewConn(c.(net.Conn))
+	p := &PacketConn{
+		genericOpt:     genericOpt{Conn: cc},
+		dgramOpt:       dgramOpt{Conn: cc},
+		payloadHandler: payloadHandler{PacketConn: c, Conn: cc},
+	}
+	return p
+}
+
+// A RawConn represents a packet network endpoint that uses the IPv4
+// transport. It is used to control several IP-level socket options
+// including IPv4 header manipulation. It also provides datagram
+// based network I/O methods specific to the IPv4 and higher layer
+// protocols that handle IPv4 datagram directly such as OSPF, GRE.
+type RawConn struct {
+	genericOpt
+	dgramOpt
+	packetHandler
+}
+
+// SetControlMessage sets the per packet IP-level socket options.
+func (c *RawConn) SetControlMessage(cf ControlFlags, on bool) error {
+	if !c.packetHandler.ok() {
+		return syscall.EINVAL
+	}
+	return setControlMessage(c.dgramOpt.Conn, &c.packetHandler.rawOpt, cf, on)
+}
+
+// SetDeadline sets the read and write deadlines associated with the
+// endpoint.
+func (c *RawConn) SetDeadline(t time.Time) error {
+	if !c.packetHandler.ok() {
+		return syscall.EINVAL
+	}
+	return c.packetHandler.IPConn.SetDeadline(t)
+}
+
+// SetReadDeadline sets the read deadline associated with the
+// endpoint.
+func (c *RawConn) SetReadDeadline(t time.Time) error {
+	if !c.packetHandler.ok() {
+		return syscall.EINVAL
+	}
+	return c.packetHandler.IPConn.SetReadDeadline(t)
+}
+
+// SetWriteDeadline sets the write deadline associated with the
+// endpoint.
+func (c *RawConn) SetWriteDeadline(t time.Time) error {
+	if !c.packetHandler.ok() {
+		return syscall.EINVAL
+	}
+	return c.packetHandler.IPConn.SetWriteDeadline(t)
+}
+
+// Close closes the endpoint.
+func (c *RawConn) Close() error {
+	if !c.packetHandler.ok() {
+		return syscall.EINVAL
+	}
+	return c.packetHandler.IPConn.Close()
+}
+
+// NewRawConn returns a new RawConn using c as its underlying
+// transport.
+func NewRawConn(c net.PacketConn) (*RawConn, error) {
+	cc, err := socket.NewConn(c.(net.Conn))
+	if err != nil {
+		return nil, err
+	}
+	r := &RawConn{
+		genericOpt:    genericOpt{Conn: cc},
+		dgramOpt:      dgramOpt{Conn: cc},
+		packetHandler: packetHandler{IPConn: c.(*net.IPConn), Conn: cc},
+	}
+	so, ok := sockOpts[ssoHeaderPrepend]
+	if !ok {
+		return nil, errOpNoSupport
+	}
+	if err := so.SetInt(r.dgramOpt.Conn, boolint(true)); err != nil {
+		return nil, err
+	}
+	return r, nil
+}