diff --git a/MdeModulePkg/Universal/Network/Tcp4Dxe/Tcp4Misc.c b/MdeModulePkg/Universal/Network/Tcp4Dxe/Tcp4Misc.c
index 1a7c41aa0b..892d19b072 100644
--- a/MdeModulePkg/Universal/Network/Tcp4Dxe/Tcp4Misc.c
+++ b/MdeModulePkg/Universal/Network/Tcp4Dxe/Tcp4Misc.c
@@ -1,7 +1,7 @@
/** @file
Misc support routines for tcp.
-Copyright (c) 2005 - 2016, Intel Corporation. All rights reserved.
+Copyright (c) 2005 - 2017, Intel Corporation. All rights reserved.
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
@@ -78,7 +78,8 @@ TcpInitTcbLocal (
// First window size is never scaled
//
Tcb->RcvWndScale = 0;
-
+ Tcb->RetxmitSeqMax = 0;
+
Tcb->ProbeTimerOn = FALSE;
}
diff --git a/MdeModulePkg/Universal/Network/Tcp4Dxe/Tcp4Output.c b/MdeModulePkg/Universal/Network/Tcp4Dxe/Tcp4Output.c
index 0eec8f07b9..5a3d837e1d 100644
--- a/MdeModulePkg/Universal/Network/Tcp4Dxe/Tcp4Output.c
+++ b/MdeModulePkg/Universal/Network/Tcp4Dxe/Tcp4Output.c
@@ -1,7 +1,7 @@
/** @file
TCP output process routines.
-Copyright (c) 2005 - 2016, Intel Corporation. All rights reserved.
+Copyright (c) 2005 - 2017, Intel Corporation. All rights reserved.
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
@@ -671,17 +671,39 @@ TcpRetransmit (
// 2. must in the current send window
// 3. will not change the boundaries of queued segments.
//
- if (TCP_SEQ_LT (Tcb->SndWl2 + Tcb->SndWnd, Seq)) {
- DEBUG ((EFI_D_WARN, "TcpRetransmit: retransmission cancelled "
- "because send window too small for TCB %p\n", Tcb));
+
+ //
+ // Handle the Window Retraction if TCP window scale is enabled according to RFC7323:
+ // On first retransmission, or if the sequence number is out of
+ // window by less than 2^Rcv.Wind.Shift, then do normal
+ // retransmission(s) without regard to the receiver window as long
+ // as the original segment was in window when it was sent.
+ //
+ if ((Tcb->SndWndScale != 0) &&
+ (TCP_SEQ_GT (Seq, Tcb->RetxmitSeqMax) || TCP_SEQ_BETWEEN (Tcb->SndWl2 + Tcb->SndWnd, Seq, Tcb->SndWl2 + Tcb->SndWnd + (1 << Tcb->SndWndScale)))) {
+ Len = TCP_SUB_SEQ (Tcb->SndNxt, Seq);
+ DEBUG (
+ (EFI_D_WARN,
+ "TcpRetransmit: retransmission without regard to the receiver window for TCB %p\n",
+ Tcb)
+ );
+
+ } else if (TCP_SEQ_GEQ (Tcb->SndWl2 + Tcb->SndWnd, Seq)) {
+ Len = TCP_SUB_SEQ (Tcb->SndWl2 + Tcb->SndWnd, Seq);
+
+ } else {
+ DEBUG (
+ (EFI_D_WARN,
+ "TcpRetransmit: retransmission cancelled because send window too small for TCB %p\n",
+ Tcb)
+ );
return 0;
}
+
+ Len = MIN (Len, Tcb->SndMss);
- Len = TCP_SUB_SEQ (Tcb->SndWl2 + Tcb->SndWnd, Seq);
- Len = MIN (Len, Tcb->SndMss);
-
- Nbuf = TcpGetSegmentSndQue (Tcb, Seq, Len);
+ Nbuf = TcpGetSegmentSndQue (Tcb, Seq, Len);
if (Nbuf == NULL) {
return -1;
}
@@ -691,6 +713,10 @@ TcpRetransmit (
if (TcpTransmitSegment (Tcb, Nbuf) != 0) {
goto OnError;
}
+
+ if (TCP_SEQ_GT (Seq, Tcb->RetxmitSeqMax)) {
+ Tcb->RetxmitSeqMax = Seq;
+ }
//
// The retransmitted buffer may be on the SndQue,
diff --git a/MdeModulePkg/Universal/Network/Tcp4Dxe/Tcp4Proto.h b/MdeModulePkg/Universal/Network/Tcp4Dxe/Tcp4Proto.h
index 01d6034b13..49d8a1da3b 100644
--- a/MdeModulePkg/Universal/Network/Tcp4Dxe/Tcp4Proto.h
+++ b/MdeModulePkg/Universal/Network/Tcp4Dxe/Tcp4Proto.h
@@ -1,7 +1,7 @@
/** @file
Tcp Protocol header file.
-Copyright (c) 2005 - 2010, Intel Corporation. All rights reserved.
+Copyright (c) 2005 - 2017, Intel Corporation. All rights reserved.
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
@@ -250,6 +250,12 @@ struct _TCP_CB {
UINT32 TimeWaitTimeout; ///< The TIME_WAIT time out
UINT32 ConnectTimeout; ///< The connect establishment time out
+ //
+ // RFC7323
+ // Addressing Window Retraction for TCP Window Scale Option.
+ //
+ TCP_SEQNO RetxmitSeqMax; ///< Max Seq number in previous retransmission.
+
//
// configuration for tcp provided by user
//