diff --git a/vendor/gopkg.in/jcmturner/gokrb5.v7/client/network.go b/vendor/gopkg.in/jcmturner/gokrb5.v7/client/network.go
new file mode 100644
index 0000000..19d25e6
--- /dev/null
+++ b/vendor/gopkg.in/jcmturner/gokrb5.v7/client/network.go
@@ -0,0 +1,226 @@
+package client
+
+import (
+	"bytes"
+	"encoding/binary"
+	"errors"
+	"fmt"
+	"io"
+	"net"
+	"time"
+
+	"gopkg.in/jcmturner/gokrb5.v7/iana/errorcode"
+	"gopkg.in/jcmturner/gokrb5.v7/messages"
+)
+
+// SendToKDC performs network actions to send data to the KDC.
+func (cl *Client) sendToKDC(b []byte, realm string) ([]byte, error) {
+	var rb []byte
+	if cl.Config.LibDefaults.UDPPreferenceLimit == 1 {
+		//1 means we should always use TCP
+		rb, errtcp := cl.sendKDCTCP(realm, b)
+		if errtcp != nil {
+			if e, ok := errtcp.(messages.KRBError); ok {
+				return rb, e
+			}
+			return rb, fmt.Errorf("communication error with KDC via TCP: %v", errtcp)
+		}
+		return rb, nil
+	}
+	if len(b) <= cl.Config.LibDefaults.UDPPreferenceLimit {
+		//Try UDP first, TCP second
+		rb, errudp := cl.sendKDCUDP(realm, b)
+		if errudp != nil {
+			if e, ok := errudp.(messages.KRBError); ok && e.ErrorCode != errorcode.KRB_ERR_RESPONSE_TOO_BIG {
+				// Got a KRBError from KDC
+				// If this is not a KRB_ERR_RESPONSE_TOO_BIG we will return immediately otherwise will try TCP.
+				return rb, e
+			}
+			// Try TCP
+			r, errtcp := cl.sendKDCTCP(realm, b)
+			if errtcp != nil {
+				if e, ok := errtcp.(messages.KRBError); ok {
+					// Got a KRBError
+					return r, e
+				}
+				return r, fmt.Errorf("failed to communicate with KDC. Attempts made with UDP (%v) and then TCP (%v)", errudp, errtcp)
+			}
+			rb = r
+		}
+		return rb, nil
+	}
+	//Try TCP first, UDP second
+	rb, errtcp := cl.sendKDCTCP(realm, b)
+	if errtcp != nil {
+		if e, ok := errtcp.(messages.KRBError); ok {
+			// Got a KRBError from KDC so returning and not trying UDP.
+			return rb, e
+		}
+		rb, errudp := cl.sendKDCUDP(realm, b)
+		if errudp != nil {
+			if e, ok := errudp.(messages.KRBError); ok {
+				// Got a KRBError
+				return rb, e
+			}
+			return rb, fmt.Errorf("failed to communicate with KDC. Attempts made with TCP (%v) and then UDP (%v)", errtcp, errudp)
+		}
+	}
+	return rb, nil
+}
+
+// dialKDCTCP establishes a UDP connection to a KDC.
+func dialKDCUDP(count int, kdcs map[int]string) (conn *net.UDPConn, err error) {
+	i := 1
+	for i <= count {
+		udpAddr, e := net.ResolveUDPAddr("udp", kdcs[i])
+		if e != nil {
+			err = fmt.Errorf("error resolving KDC address: %v", e)
+			return
+		}
+		conn, err = net.DialUDP("udp", nil, udpAddr)
+		if err == nil {
+			err = conn.SetDeadline(time.Now().Add(5 * time.Second))
+			if err != nil {
+				return
+			}
+			return
+		}
+		i++
+	}
+	err = errors.New("error in getting a UDP connection to any of the KDCs")
+	return
+}
+
+// dialKDCTCP establishes a TCP connection to a KDC.
+func dialKDCTCP(count int, kdcs map[int]string) (conn *net.TCPConn, err error) {
+	i := 1
+	for i <= count {
+		tcpAddr, e := net.ResolveTCPAddr("tcp", kdcs[i])
+		if e != nil {
+			err = fmt.Errorf("error resolving KDC address: %v", e)
+			return
+		}
+		conn, err = net.DialTCP("tcp", nil, tcpAddr)
+		if err == nil {
+			err = conn.SetDeadline(time.Now().Add(5 * time.Second))
+			if err != nil {
+				return
+			}
+			return
+		}
+		i++
+	}
+	err = errors.New("error in getting a TCP connection to any of the KDCs")
+	return
+}
+
+// sendKDCUDP sends bytes to the KDC via UDP.
+func (cl *Client) sendKDCUDP(realm string, b []byte) ([]byte, error) {
+	var r []byte
+	count, kdcs, err := cl.Config.GetKDCs(realm, false)
+	if err != nil {
+		return r, err
+	}
+	conn, err := dialKDCUDP(count, kdcs)
+	if err != nil {
+		return r, err
+	}
+	r, err = cl.sendUDP(conn, b)
+	if err != nil {
+		return r, err
+	}
+	return checkForKRBError(r)
+}
+
+// sendKDCTCP sends bytes to the KDC via TCP.
+func (cl *Client) sendKDCTCP(realm string, b []byte) ([]byte, error) {
+	var r []byte
+	count, kdcs, err := cl.Config.GetKDCs(realm, true)
+	if err != nil {
+		return r, err
+	}
+	conn, err := dialKDCTCP(count, kdcs)
+	if err != nil {
+		return r, err
+	}
+	rb, err := cl.sendTCP(conn, b)
+	if err != nil {
+		return r, err
+	}
+	return checkForKRBError(rb)
+}
+
+// sendUDP sends bytes to connection over UDP.
+func (cl *Client) sendUDP(conn *net.UDPConn, b []byte) ([]byte, error) {
+	var r []byte
+	defer conn.Close()
+	_, err := conn.Write(b)
+	if err != nil {
+		return r, fmt.Errorf("error sending to (%s): %v", conn.RemoteAddr().String(), err)
+	}
+	udpbuf := make([]byte, 4096)
+	n, _, err := conn.ReadFrom(udpbuf)
+	r = udpbuf[:n]
+	if err != nil {
+		return r, fmt.Errorf("sending over UDP failed to %s: %v", conn.RemoteAddr().String(), err)
+	}
+	if len(r) < 1 {
+		return r, fmt.Errorf("no response data from %s", conn.RemoteAddr().String())
+	}
+	return r, nil
+}
+
+// sendTCP sends bytes to connection over TCP.
+func (cl *Client) sendTCP(conn *net.TCPConn, b []byte) ([]byte, error) {
+	defer conn.Close()
+	var r []byte
+	/*
+		RFC https://tools.ietf.org/html/rfc4120#section-7.2.2
+		Each request (KRB_KDC_REQ) and response (KRB_KDC_REP or KRB_ERROR)
+		sent over the TCP stream is preceded by the length of the request as
+		4 octets in network byte order.  The high bit of the length is
+		reserved for future expansion and MUST currently be set to zero.  If
+		a KDC that does not understand how to interpret a set high bit of the
+		length encoding receives a request with the high order bit of the
+		length set, it MUST return a KRB-ERROR message with the error
+		KRB_ERR_FIELD_TOOLONG and MUST close the TCP stream.
+		NB: network byte order == big endian
+	*/
+	var buf bytes.Buffer
+	err := binary.Write(&buf, binary.BigEndian, uint32(len(b)))
+	if err != nil {
+		return r, err
+	}
+	b = append(buf.Bytes(), b...)
+
+	_, err = conn.Write(b)
+	if err != nil {
+		return r, fmt.Errorf("error sending to KDC (%s): %v", conn.RemoteAddr().String(), err)
+	}
+
+	sh := make([]byte, 4, 4)
+	_, err = conn.Read(sh)
+	if err != nil {
+		return r, fmt.Errorf("error reading response size header: %v", err)
+	}
+	s := binary.BigEndian.Uint32(sh)
+
+	rb := make([]byte, s, s)
+	_, err = io.ReadFull(conn, rb)
+	if err != nil {
+		return r, fmt.Errorf("error reading response: %v", err)
+	}
+	if len(rb) < 1 {
+		return r, fmt.Errorf("no response data from KDC %s", conn.RemoteAddr().String())
+	}
+	return rb, nil
+}
+
+// checkForKRBError checks if the response bytes from the KDC are a KRBError.
+func checkForKRBError(b []byte) ([]byte, error) {
+	var KRBErr messages.KRBError
+	if err := KRBErr.Unmarshal(b); err == nil {
+		return b, KRBErr
+	}
+	return b, nil
+}