diff --git a/vendor/gopkg.in/Shopify/sarama.v1/mockbroker.go b/vendor/gopkg.in/Shopify/sarama.v1/mockbroker.go
index 55ef1e2..4ed46a6 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/mockbroker.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/mockbroker.go
@@ -18,6 +18,8 @@
 	expectationTimeout = 500 * time.Millisecond
 )
 
+type GSSApiHandlerFunc func([]byte) []byte
+
 type requestHandlerFunc func(req *request) (res encoder)
 
 // RequestNotifierFunc is invoked when a mock broker processes a request successfully
@@ -49,18 +51,19 @@
 // It is not necessary to prefix message length or correlation ID to your
 // response bytes, the server does that automatically as a convenience.
 type MockBroker struct {
-	brokerID     int32
-	port         int32
-	closing      chan none
-	stopper      chan none
-	expectations chan encoder
-	listener     net.Listener
-	t            TestReporter
-	latency      time.Duration
-	handler      requestHandlerFunc
-	notifier     RequestNotifierFunc
-	history      []RequestResponse
-	lock         sync.Mutex
+	brokerID      int32
+	port          int32
+	closing       chan none
+	stopper       chan none
+	expectations  chan encoder
+	listener      net.Listener
+	t             TestReporter
+	latency       time.Duration
+	handler       requestHandlerFunc
+	notifier      RequestNotifierFunc
+	history       []RequestResponse
+	lock          sync.Mutex
+	gssApiHandler GSSApiHandlerFunc
 }
 
 // RequestResponse represents a Request/Response pair processed by MockBroker.
@@ -173,6 +176,43 @@
 	Logger.Printf("*** mockbroker/%d: listener closed, err=%v", b.BrokerID(), err)
 }
 
+func (b *MockBroker) SetGSSAPIHandler(handler GSSApiHandlerFunc) {
+	b.gssApiHandler = handler
+}
+
+func (b *MockBroker) readToBytes(r io.Reader) ([]byte, error) {
+	var (
+		bytesRead   int
+		lengthBytes = make([]byte, 4)
+	)
+
+	if _, err := io.ReadFull(r, lengthBytes); err != nil {
+		return nil, err
+	}
+
+	bytesRead += len(lengthBytes)
+	length := int32(binary.BigEndian.Uint32(lengthBytes))
+
+	if length <= 4 || length > MaxRequestSize {
+		return nil, PacketDecodingError{fmt.Sprintf("message of length %d too large or too small", length)}
+	}
+
+	encodedReq := make([]byte, length)
+	if _, err := io.ReadFull(r, encodedReq); err != nil {
+		return nil, err
+	}
+
+	bytesRead += len(encodedReq)
+
+	fullBytes := append(lengthBytes, encodedReq...)
+
+	return fullBytes, nil
+}
+
+func (b *MockBroker) isGSSAPI(buffer []byte) bool {
+	return buffer[4] == 0x60 || bytes.Equal(buffer[4:6], []byte{0x05, 0x04})
+}
+
 func (b *MockBroker) handleRequests(conn net.Conn, idx int, wg *sync.WaitGroup) {
 	defer wg.Done()
 	defer func() {
@@ -192,59 +232,92 @@
 	}()
 
 	resHeader := make([]byte, 8)
+	var bytesWritten int
+	var bytesRead int
 	for {
-		req, bytesRead, err := decodeRequest(conn)
+
+		buffer, err := b.readToBytes(conn)
 		if err != nil {
-			Logger.Printf("*** mockbroker/%d/%d: invalid request: err=%+v, %+v", b.brokerID, idx, err, spew.Sdump(req))
+			Logger.Printf("*** mockbroker/%d/%d: invalid request: err=%+v, %+v", b.brokerID, idx, err, spew.Sdump(buffer))
 			b.serverError(err)
 			break
 		}
 
-		if b.latency > 0 {
-			time.Sleep(b.latency)
-		}
+		bytesWritten = 0
+		if !b.isGSSAPI(buffer) {
 
-		b.lock.Lock()
-		res := b.handler(req)
-		b.history = append(b.history, RequestResponse{req.body, res})
-		b.lock.Unlock()
-
-		if res == nil {
-			Logger.Printf("*** mockbroker/%d/%d: ignored %v", b.brokerID, idx, spew.Sdump(req))
-			continue
-		}
-		Logger.Printf("*** mockbroker/%d/%d: served %v -> %v", b.brokerID, idx, req, res)
-
-		encodedRes, err := encode(res, nil)
-		if err != nil {
-			b.serverError(err)
-			break
-		}
-		if len(encodedRes) == 0 {
-			b.lock.Lock()
-			if b.notifier != nil {
-				b.notifier(bytesRead, 0)
+			req, br, err := decodeRequest(bytes.NewReader(buffer))
+			bytesRead = br
+			if err != nil {
+				Logger.Printf("*** mockbroker/%d/%d: invalid request: err=%+v, %+v", b.brokerID, idx, err, spew.Sdump(req))
+				b.serverError(err)
+				break
 			}
-			b.lock.Unlock()
-			continue
-		}
 
-		binary.BigEndian.PutUint32(resHeader, uint32(len(encodedRes)+4))
-		binary.BigEndian.PutUint32(resHeader[4:], uint32(req.correlationID))
-		if _, err = conn.Write(resHeader); err != nil {
-			b.serverError(err)
-			break
-		}
-		if _, err = conn.Write(encodedRes); err != nil {
-			b.serverError(err)
-			break
+			if b.latency > 0 {
+				time.Sleep(b.latency)
+			}
+
+			b.lock.Lock()
+			res := b.handler(req)
+			b.history = append(b.history, RequestResponse{req.body, res})
+			b.lock.Unlock()
+
+			if res == nil {
+				Logger.Printf("*** mockbroker/%d/%d: ignored %v", b.brokerID, idx, spew.Sdump(req))
+				continue
+			}
+			Logger.Printf("*** mockbroker/%d/%d: served %v -> %v", b.brokerID, idx, req, res)
+
+			encodedRes, err := encode(res, nil)
+			if err != nil {
+				b.serverError(err)
+				break
+			}
+			if len(encodedRes) == 0 {
+				b.lock.Lock()
+				if b.notifier != nil {
+					b.notifier(bytesRead, 0)
+				}
+				b.lock.Unlock()
+				continue
+			}
+
+			binary.BigEndian.PutUint32(resHeader, uint32(len(encodedRes)+4))
+			binary.BigEndian.PutUint32(resHeader[4:], uint32(req.correlationID))
+			if _, err = conn.Write(resHeader); err != nil {
+				b.serverError(err)
+				break
+			}
+			if _, err = conn.Write(encodedRes); err != nil {
+				b.serverError(err)
+				break
+			}
+			bytesWritten = len(resHeader) + len(encodedRes)
+
+		} else {
+			// GSSAPI is not part of kafka protocol, but is supported for authentication proposes.
+			// Don't support history for this kind of request as is only used for test GSSAPI authentication mechanism
+			b.lock.Lock()
+			res := b.gssApiHandler(buffer)
+			b.lock.Unlock()
+			if res == nil {
+				Logger.Printf("*** mockbroker/%d/%d: ignored %v", b.brokerID, idx, spew.Sdump(buffer))
+				continue
+			}
+			if _, err = conn.Write(res); err != nil {
+				b.serverError(err)
+				break
+			}
+			bytesWritten = len(res)
 		}
 
 		b.lock.Lock()
 		if b.notifier != nil {
-			b.notifier(bytesRead, len(resHeader)+len(encodedRes))
+			b.notifier(bytesRead, bytesWritten)
 		}
 		b.lock.Unlock()
+
 	}
 	Logger.Printf("*** mockbroker/%d/%d: connection closed, err=%v", b.BrokerID(), idx, err)
 }