[mirror_edk2.git] / MdeModulePkg / Universal / Network / Tcp4Dxe / Tcp4Option.c

/** @file\r
\r
Copyright (c) 2005 - 2006, Intel Corporation\r
All rights reserved. This program and the accompanying materials\r
are licensed and made available under the terms and conditions of the BSD License\r
which accompanies this distribution.  The full text of the license may be found at\r
http://opensource.org/licenses/bsd-license.php\r
\r
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
\r
Module Name:\r
\r
  Tcp4Option.c\r
\r
Abstract:\r
\r
  Routines to process TCP option.\r
\r
\r
**/\r
\r
#include "Tcp4Main.h"\r
\r
STATIC\r
UINT16\r
TcpGetUint16 (\r
  IN UINT8 *Buf\r
  )\r
{\r
  UINT16  Value;\r
  NetCopyMem (&Value, Buf, sizeof (UINT16));\r
  return NTOHS (Value);\r
}\r
\r
STATIC\r
VOID\r
TcpPutUint16 (\r
  IN UINT8  *Buf,\r
  IN UINT16 Data\r
  )\r
{\r
  Data = HTONS (Data);\r
  NetCopyMem (Buf, &Data, sizeof (UINT16));\r
}\r
\r
STATIC\r
UINT32\r
TcpGetUint32 (\r
  IN UINT8 *Buf\r
  )\r
{\r
  UINT32  Value;\r
  NetCopyMem (&Value, Buf, sizeof (UINT32));\r
  return NTOHL (Value);\r
}\r
\r
STATIC\r
VOID\r
TcpPutUint32 (\r
  IN UINT8  *Buf,\r
  IN UINT32 Data\r
  )\r
{\r
  Data = HTONL (Data);\r
  NetCopyMem (Buf, &Data, sizeof (UINT32));\r
}\r
\r
\r
/**\r
  Compute the window scale value according to the given\r
  buffer size.\r
\r
  @param  Tcb     Pointer to the TCP_CB of this TCP instance.\r
\r
  @retval UINT8   The scale value.\r
\r
**/\r
UINT8\r
TcpComputeScale (\r
  IN TCP_CB *Tcb\r
  )\r
{\r
  UINT8   Scale;\r
  UINT32  BufSize;\r
\r
  ASSERT (Tcb && Tcb->Sk);\r
\r
  BufSize = GET_RCV_BUFFSIZE (Tcb->Sk);\r
\r
  Scale   = 0;\r
  while ((Scale < TCP_OPTION_MAX_WS) &&\r
         ((UINT32) (TCP_OPTION_MAX_WIN << Scale) < BufSize)) {\r
\r
    Scale++;\r
  }\r
\r
  return Scale;\r
}\r
\r
\r
/**\r
  Build the TCP option in three-way handshake.\r
\r
  @param  Tcb     Pointer to the TCP_CB of this TCP instance.\r
  @param  Nbuf    Pointer to the buffer to store the options.\r
\r
  @return The total length of the TCP option field.\r
\r
**/\r
UINT16\r
TcpSynBuildOption (\r
  IN TCP_CB  *Tcb,\r
  IN NET_BUF *Nbuf\r
  )\r
{\r
  UINT8   *Data;\r
  UINT16  Len;\r
\r
  ASSERT (Tcb && Nbuf && !Nbuf->Tcp);\r
\r
  Len = 0;\r
\r
  //\r
  // Add timestamp option if not disabled by application\r
  // and it is the first SYN segment or the peer has sent\r
  // us its timestamp.\r
  //\r
  if (!TCP_FLG_ON (Tcb->CtrlFlag, TCP_CTRL_NO_TS) &&\r
      (!TCP_FLG_ON (TCPSEG_NETBUF (Nbuf)->Flag, TCP_FLG_ACK) ||\r
      TCP_FLG_ON (Tcb->CtrlFlag, TCP_CTRL_RCVD_TS))) {\r
\r
    Data = NetbufAllocSpace (\r
            Nbuf,\r
            TCP_OPTION_TS_ALIGNED_LEN,\r
            NET_BUF_HEAD\r
            );\r
\r
    ASSERT (Data);\r
    Len += TCP_OPTION_TS_ALIGNED_LEN;\r
\r
    TcpPutUint32 (Data, TCP_OPTION_TS_FAST);\r
    TcpPutUint32 (Data + 4, mTcpTick);\r
    TcpPutUint32 (Data + 8, 0);\r
  }\r
\r
  //\r
  // Build window scale option, only when are configured\r
  // to send WS option, and either we are doing active\r
  // open or we have received WS option from peer.\r
  //\r
  if (!TCP_FLG_ON (Tcb->CtrlFlag, TCP_CTRL_NO_WS) &&\r
      (!TCP_FLG_ON (TCPSEG_NETBUF (Nbuf)->Flag, TCP_FLG_ACK) ||\r
      TCP_FLG_ON (Tcb->CtrlFlag, TCP_CTRL_RCVD_WS))) {\r
\r
    Data = NetbufAllocSpace (\r
            Nbuf,\r
            TCP_OPTION_WS_ALIGNED_LEN,\r
            NET_BUF_HEAD\r
            );\r
\r
    ASSERT (Data);\r
\r
    Len += TCP_OPTION_WS_ALIGNED_LEN;\r
    TcpPutUint32 (Data, TCP_OPTION_WS_FAST | TcpComputeScale (Tcb));\r
  }\r
\r
  //\r
  // Build MSS option\r
  //\r
  Data = NetbufAllocSpace (Nbuf, TCP_OPTION_MSS_LEN, 1);\r
  ASSERT (Data);\r
\r
  Len += TCP_OPTION_MSS_LEN;\r
  TcpPutUint32 (Data, TCP_OPTION_MSS_FAST | Tcb->RcvMss);\r
\r
  return Len;\r
}\r
\r
\r
/**\r
  Build the TCP option in synchronized states.\r
\r
  @param  Tcb     Pointer to the TCP_CB of this TCP instance.\r
  @param  Nbuf    Pointer to the buffer to store the options.\r
\r
  @return The total length of the TCP option field.\r
\r
**/\r
UINT16\r
TcpBuildOption (\r
  IN TCP_CB  *Tcb,\r
  IN NET_BUF *Nbuf\r
  )\r
{\r
  UINT8   *Data;\r
  UINT16  Len;\r
\r
  ASSERT (Tcb && Nbuf && !Nbuf->Tcp);\r
  Len = 0;\r
\r
  //\r
  // Build Timestamp option\r
  //\r
  if (TCP_FLG_ON (Tcb->CtrlFlag, TCP_CTRL_SND_TS) &&\r
      !TCP_FLG_ON (TCPSEG_NETBUF (Nbuf)->Flag, TCP_FLG_RST)) {\r
\r
    Data = NetbufAllocSpace (\r
            Nbuf,\r
            TCP_OPTION_TS_ALIGNED_LEN,\r
            NET_BUF_HEAD\r
            );\r
\r
    ASSERT (Data);\r
    Len += TCP_OPTION_TS_ALIGNED_LEN;\r
\r
    TcpPutUint32 (Data, TCP_OPTION_TS_FAST);\r
    TcpPutUint32 (Data + 4, mTcpTick);\r
    TcpPutUint32 (Data + 8, Tcb->TsRecent);\r
  }\r
\r
  return Len;\r
}\r
\r
\r
/**\r
  Parse the supported options.\r
\r
  @param  Tcp     Pointer to the TCP_CB of this TCP instance.\r
  @param  Option  Pointer to the TCP_OPTION used to store the successfully pasrsed\r
                  options.\r
\r
  @retval 0       The options are successfully pasrsed.\r
  @retval -1      Ilegal option was found.\r
\r
**/\r
INTN\r
TcpParseOption (\r
  IN TCP_HEAD   *Tcp,\r
  IN TCP_OPTION *Option\r
  )\r
{\r
  UINT8 *Head;\r
  UINT8 TotalLen;\r
  UINT8 Cur;\r
  UINT8 Type;\r
  UINT8 Len;\r
\r
  ASSERT (Tcp && Option);\r
\r
  Option->Flag  = 0;\r
\r
  TotalLen      = (Tcp->HeadLen << 2) - sizeof (TCP_HEAD);\r
  if (TotalLen <= 0) {\r
    return 0;\r
  }\r
\r
  Head = (UINT8 *) (Tcp + 1);\r
\r
  //\r
  // Fast process of timestamp option\r
  //\r
  if ((TotalLen == TCP_OPTION_TS_ALIGNED_LEN) &&\r
      (TcpGetUint32 (Head) == TCP_OPTION_TS_FAST)) {\r
\r
    Option->TSVal = TcpGetUint32 (Head + 4);\r
    Option->TSEcr = TcpGetUint32 (Head + 8);\r
    Option->Flag  = TCP_OPTION_RCVD_TS;\r
\r
    return 0;\r
  }\r
\r
  //\r
  // Slow path to process the options.\r
  //\r
  Cur = 0;\r
\r
  while (Cur < TotalLen) {\r
    Type = Head[Cur];\r
\r
    switch (Type) {\r
    case TCP_OPTION_MSS:\r
      Len = Head[Cur + 1];\r
\r
      if ((Len != TCP_OPTION_MSS_LEN) ||\r
          (TotalLen - Cur < TCP_OPTION_MSS_LEN)) {\r
\r
        return -1;\r
      }\r
\r
      Option->Mss = TcpGetUint16 (&Head[Cur + 2]);\r
      TCP_SET_FLG (Option->Flag, TCP_OPTION_RCVD_MSS);\r
\r
      Cur += TCP_OPTION_MSS_LEN;\r
      break;\r
\r
    case TCP_OPTION_WS:\r
      Len = Head[Cur + 1];\r
\r
      if ((Len != TCP_OPTION_WS_LEN) ||\r
          (TotalLen - Cur < TCP_OPTION_WS_LEN)) {\r
\r
        return -1;\r
      }\r
\r
      Option->WndScale = (UINT8) NET_MIN (14, Head[Cur + 2]);\r
      TCP_SET_FLG (Option->Flag, TCP_OPTION_RCVD_WS);\r
\r
      Cur += TCP_OPTION_WS_LEN;\r
      break;\r
\r
    case TCP_OPTION_TS:\r
      Len = Head[Cur + 1];\r
\r
      if ((Len != TCP_OPTION_TS_LEN) ||\r
          (TotalLen - Cur < TCP_OPTION_TS_LEN)) {\r
\r
        return -1;\r
      }\r
\r
      Option->TSVal = TcpGetUint32 (&Head[Cur + 2]);\r
      Option->TSEcr = TcpGetUint32 (&Head[Cur + 6]);\r
      TCP_SET_FLG (Option->Flag, TCP_OPTION_RCVD_TS);\r
\r
      Cur += TCP_OPTION_TS_LEN;\r
      break;\r
\r
    case TCP_OPTION_NOP:\r
      Cur++;\r
      break;\r
\r
    case TCP_OPTION_EOP:\r
      Cur = TotalLen;\r
      break;\r
\r
    default:\r
      Len = Head[Cur + 1];\r
\r
      if (TotalLen - Cur < Len || Len < 2) {\r
        return -1;\r
      }\r
\r
      Cur = (UINT8) (Cur + Len);\r
      break;\r
    }\r
\r
  }\r
\r
  return 0;\r
}\r
\r
\r
/**\r
  Check the segment against PAWS.\r
\r
  @param  Tcb     Pointer to the TCP_CB of this TCP instance.\r
  @param  TSVal   The timestamp value.\r
\r
  @retval 1       The segment passed the PAWS check.\r
  @retval 0       The segment failed to pass the PAWS check.\r
\r
**/\r
UINT32\r
TcpPawsOK (\r
  IN TCP_CB *Tcb,\r
  IN UINT32 TSVal\r
  )\r
{\r
  //\r
  // PAWS as defined in RFC1323, buggy...\r
  //\r
  if (TCP_TIME_LT (TSVal, Tcb->TsRecent) &&\r
      TCP_TIME_LT (Tcb->TsRecentAge + TCP_PAWS_24DAY, mTcpTick)) {\r
\r
    return 0;\r
\r
  }\r
\r
  return 1;\r
}\r
Commit	Line	Data
8a67d61d	1	/** @file\r
	2	\r
	3	Copyright (c) 2005 - 2006, Intel Corporation\r
	4	All rights reserved. This program and the accompanying materials\r
	5	are licensed and made available under the terms and conditions of the BSD License\r
	6	which accompanies this distribution. The full text of the license may be found at\r
	7	http://opensource.org/licenses/bsd-license.php\r
	8	\r
	9	THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
	10	WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
	11	\r
	12	Module Name:\r
	13	\r
	14	Tcp4Option.c\r
	15	\r
	16	Abstract:\r
	17	\r
	18	Routines to process TCP option.\r
	19	\r
	20	\r
	21	**/\r
	22	\r
	23	#include "Tcp4Main.h"\r
	24	\r
	25	STATIC\r
	26	UINT16\r
	27	TcpGetUint16 (\r
	28	IN UINT8 *Buf\r
	29	)\r
	30	{\r
	31	UINT16 Value;\r
	32	NetCopyMem (&Value, Buf, sizeof (UINT16));\r
	33	return NTOHS (Value);\r
	34	}\r
	35	\r
	36	STATIC\r
	37	VOID\r
	38	TcpPutUint16 (\r
	39	IN UINT8 *Buf,\r
	40	IN UINT16 Data\r
	41	)\r
	42	{\r
	43	Data = HTONS (Data);\r
	44	NetCopyMem (Buf, &Data, sizeof (UINT16));\r
	45	}\r
	46	\r
	47	STATIC\r
	48	UINT32\r
	49	TcpGetUint32 (\r
	50	IN UINT8 *Buf\r
	51	)\r
	52	{\r
	53	UINT32 Value;\r
	54	NetCopyMem (&Value, Buf, sizeof (UINT32));\r
	55	return NTOHL (Value);\r
	56	}\r
	57	\r
	58	STATIC\r
	59	VOID\r
	60	TcpPutUint32 (\r
	61	IN UINT8 *Buf,\r
	62	IN UINT32 Data\r
	63	)\r
	64	{\r
65	Data = HTONL (Data);\r
66	NetCopyMem (Buf, &Data, sizeof (UINT32));\r
67	}\r
68	\r
69	\r
70	/**\r
71	Compute the window scale value according to the given\r
72	buffer size.\r
73	\r
74	@param Tcb Pointer to the TCP_CB of this TCP instance.\r
75	\r
76	@retval UINT8 The scale value.\r
77	\r
78	**/\r
79	UINT8\r
80	TcpComputeScale (\r
81	IN TCP_CB *Tcb\r
82	)\r
83	{\r
84	UINT8 Scale;\r
85	UINT32 BufSize;\r
86	\r
87	ASSERT (Tcb && Tcb->Sk);\r
88	\r
89	BufSize = GET_RCV_BUFFSIZE (Tcb->Sk);\r
90	\r
91	Scale = 0;\r
92	while ((Scale < TCP_OPTION_MAX_WS) &&\r
93	((UINT32) (TCP_OPTION_MAX_WIN << Scale) < BufSize)) {\r
94	\r
95	Scale++;\r
96	}\r
97	\r
98	return Scale;\r
99	}\r
100	\r
101	\r
102	/**\r
103	Build the TCP option in three-way handshake.\r
104	\r
105	@param Tcb Pointer to the TCP_CB of this TCP instance.\r
106	@param Nbuf Pointer to the buffer to store the options.\r
107	\r
108	@return The total length of the TCP option field.\r
109	\r
110	**/\r
111	UINT16\r
112	TcpSynBuildOption (\r
113	IN TCP_CB *Tcb,\r
114	IN NET_BUF *Nbuf\r
115	)\r
116	{\r
4eb65aff	117	UINT8 *Data;\r
8a67d61d	118	UINT16 Len;\r
	119	\r
	120	ASSERT (Tcb && Nbuf && !Nbuf->Tcp);\r
	121	\r
	122	Len = 0;\r
	123	\r
	124	//\r
	125	// Add timestamp option if not disabled by application\r
	126	// and it is the first SYN segment or the peer has sent\r
	127	// us its timestamp.\r
	128	//\r
	129	if (!TCP_FLG_ON (Tcb->CtrlFlag, TCP_CTRL_NO_TS) &&\r
	130	(!TCP_FLG_ON (TCPSEG_NETBUF (Nbuf)->Flag, TCP_FLG_ACK) \|\|\r
	131	TCP_FLG_ON (Tcb->CtrlFlag, TCP_CTRL_RCVD_TS))) {\r
	132	\r
	133	Data = NetbufAllocSpace (\r
	134	Nbuf,\r
	135	TCP_OPTION_TS_ALIGNED_LEN,\r
	136	NET_BUF_HEAD\r
	137	);\r
	138	\r
	139	ASSERT (Data);\r
	140	Len += TCP_OPTION_TS_ALIGNED_LEN;\r
	141	\r
	142	TcpPutUint32 (Data, TCP_OPTION_TS_FAST);\r
	143	TcpPutUint32 (Data + 4, mTcpTick);\r
	144	TcpPutUint32 (Data + 8, 0);\r
	145	}\r
	146	\r
	147	//\r
	148	// Build window scale option, only when are configured\r
	149	// to send WS option, and either we are doing active\r
	150	// open or we have received WS option from peer.\r
	151	//\r
	152	if (!TCP_FLG_ON (Tcb->CtrlFlag, TCP_CTRL_NO_WS) &&\r
	153	(!TCP_FLG_ON (TCPSEG_NETBUF (Nbuf)->Flag, TCP_FLG_ACK) \|\|\r
	154	TCP_FLG_ON (Tcb->CtrlFlag, TCP_CTRL_RCVD_WS))) {\r
	155	\r
	156	Data = NetbufAllocSpace (\r
	157	Nbuf,\r
	158	TCP_OPTION_WS_ALIGNED_LEN,\r
	159	NET_BUF_HEAD\r
	160	);\r
	161	\r
	162	ASSERT (Data);\r
	163	\r
	164	Len += TCP_OPTION_WS_ALIGNED_LEN;\r
	165	TcpPutUint32 (Data, TCP_OPTION_WS_FAST \| TcpComputeScale (Tcb));\r
	166	}\r
	167	\r
	168	//\r
	169	// Build MSS option\r
	170	//\r
	171	Data = NetbufAllocSpace (Nbuf, TCP_OPTION_MSS_LEN, 1);\r
	172	ASSERT (Data);\r
	173	\r
	174	Len += TCP_OPTION_MSS_LEN;\r
	175	TcpPutUint32 (Data, TCP_OPTION_MSS_FAST \| Tcb->RcvMss);\r
	176	\r
	177	return Len;\r
	178	}\r
	179	\r
	180	\r
	181	/**\r
182	Build the TCP option in synchronized states.\r
183	\r
184	@param Tcb Pointer to the TCP_CB of this TCP instance.\r
185	@param Nbuf Pointer to the buffer to store the options.\r
186	\r
187	@return The total length of the TCP option field.\r
188	\r
189	**/\r
190	UINT16\r
191	TcpBuildOption (\r
192	IN TCP_CB *Tcb,\r
193	IN NET_BUF *Nbuf\r
194	)\r
195	{\r
4eb65aff	196	UINT8 *Data;\r
8a67d61d	197	UINT16 Len;\r
	198	\r
	199	ASSERT (Tcb && Nbuf && !Nbuf->Tcp);\r
	200	Len = 0;\r
	201	\r
	202	//\r
	203	// Build Timestamp option\r
	204	//\r
	205	if (TCP_FLG_ON (Tcb->CtrlFlag, TCP_CTRL_SND_TS) &&\r
	206	!TCP_FLG_ON (TCPSEG_NETBUF (Nbuf)->Flag, TCP_FLG_RST)) {\r
	207	\r
	208	Data = NetbufAllocSpace (\r
	209	Nbuf,\r
	210	TCP_OPTION_TS_ALIGNED_LEN,\r
	211	NET_BUF_HEAD\r
	212	);\r
	213	\r
	214	ASSERT (Data);\r
	215	Len += TCP_OPTION_TS_ALIGNED_LEN;\r
	216	\r
	217	TcpPutUint32 (Data, TCP_OPTION_TS_FAST);\r
	218	TcpPutUint32 (Data + 4, mTcpTick);\r
	219	TcpPutUint32 (Data + 8, Tcb->TsRecent);\r
	220	}\r
	221	\r
	222	return Len;\r
	223	}\r
	224	\r
	225	\r
	226	/**\r
	227	Parse the supported options.\r
	228	\r
	229	@param Tcp Pointer to the TCP_CB of this TCP instance.\r
	230	@param Option Pointer to the TCP_OPTION used to store the successfully pasrsed\r
	231	options.\r
	232	\r
	233	@retval 0 The options are successfully pasrsed.\r
	234	@retval -1 Ilegal option was found.\r
	235	\r
	236	**/\r
	237	INTN\r
	238	TcpParseOption (\r
	239	IN TCP_HEAD *Tcp,\r
	240	IN TCP_OPTION *Option\r
	241	)\r
	242	{\r
	243	UINT8 *Head;\r
	244	UINT8 TotalLen;\r
	245	UINT8 Cur;\r
	246	UINT8 Type;\r
	247	UINT8 Len;\r
	248	\r
	249	ASSERT (Tcp && Option);\r
	250	\r
	251	Option->Flag = 0;\r
	252	\r
	253	TotalLen = (Tcp->HeadLen << 2) - sizeof (TCP_HEAD);\r
	254	if (TotalLen <= 0) {\r
	255	return 0;\r
	256	}\r
	257	\r
	258	Head = (UINT8 *) (Tcp + 1);\r
	259	\r
	260	//\r
261	// Fast process of timestamp option\r
262	//\r
263	if ((TotalLen == TCP_OPTION_TS_ALIGNED_LEN) &&\r
264	(TcpGetUint32 (Head) == TCP_OPTION_TS_FAST)) {\r
265	\r
266	Option->TSVal = TcpGetUint32 (Head + 4);\r
267	Option->TSEcr = TcpGetUint32 (Head + 8);\r
268	Option->Flag = TCP_OPTION_RCVD_TS;\r
269	\r
270	return 0;\r
271	}\r
272	\r
273	//\r
274	// Slow path to process the options.\r
275	//\r
276	Cur = 0;\r
277	\r
278	while (Cur < TotalLen) {\r
279	Type = Head[Cur];\r
280	\r
281	switch (Type) {\r
282	case TCP_OPTION_MSS:\r
283	Len = Head[Cur + 1];\r
284	\r
285	if ((Len != TCP_OPTION_MSS_LEN) \|\|\r
286	(TotalLen - Cur < TCP_OPTION_MSS_LEN)) {\r
287	\r
288	return -1;\r
289	}\r
290	\r
291	Option->Mss = TcpGetUint16 (&Head[Cur + 2]);\r
292	TCP_SET_FLG (Option->Flag, TCP_OPTION_RCVD_MSS);\r
293	\r
294	Cur += TCP_OPTION_MSS_LEN;\r
295	break;\r
296	\r
297	case TCP_OPTION_WS:\r
298	Len = Head[Cur + 1];\r
299	\r
300	if ((Len != TCP_OPTION_WS_LEN) \|\|\r
301	(TotalLen - Cur < TCP_OPTION_WS_LEN)) {\r
302	\r
303	return -1;\r
304	}\r
305	\r
4eb65aff	306	Option->WndScale = (UINT8) NET_MIN (14, Head[Cur + 2]);\r
8a67d61d	307	TCP_SET_FLG (Option->Flag, TCP_OPTION_RCVD_WS);\r
	308	\r
	309	Cur += TCP_OPTION_WS_LEN;\r
	310	break;\r
	311	\r
	312	case TCP_OPTION_TS:\r
	313	Len = Head[Cur + 1];\r
	314	\r
	315	if ((Len != TCP_OPTION_TS_LEN) \|\|\r
	316	(TotalLen - Cur < TCP_OPTION_TS_LEN)) {\r
	317	\r
	318	return -1;\r
	319	}\r
	320	\r
	321	Option->TSVal = TcpGetUint32 (&Head[Cur + 2]);\r
	322	Option->TSEcr = TcpGetUint32 (&Head[Cur + 6]);\r
	323	TCP_SET_FLG (Option->Flag, TCP_OPTION_RCVD_TS);\r
	324	\r
	325	Cur += TCP_OPTION_TS_LEN;\r
	326	break;\r
	327	\r
	328	case TCP_OPTION_NOP:\r
	329	Cur++;\r
	330	break;\r
	331	\r
	332	case TCP_OPTION_EOP:\r
	333	Cur = TotalLen;\r
	334	break;\r
	335	\r
	336	default:\r
	337	Len = Head[Cur + 1];\r
	338	\r
	339	if (TotalLen - Cur < Len \|\| Len < 2) {\r
	340	return -1;\r
	341	}\r
	342	\r
4eb65aff	343	Cur = (UINT8) (Cur + Len);\r
8a67d61d	344	break;\r
	345	}\r
	346	\r
	347	}\r
	348	\r
	349	return 0;\r
	350	}\r
	351	\r
	352	\r
	353	/**\r
	354	Check the segment against PAWS.\r
	355	\r
	356	@param Tcb Pointer to the TCP_CB of this TCP instance.\r
	357	@param TSVal The timestamp value.\r
	358	\r
	359	@retval 1 The segment passed the PAWS check.\r
	360	@retval 0 The segment failed to pass the PAWS check.\r
	361	\r
	362	**/\r
	363	UINT32\r
	364	TcpPawsOK (\r
	365	IN TCP_CB *Tcb,\r
	366	IN UINT32 TSVal\r
	367	)\r
	368	{\r
	369	//\r
	370	// PAWS as defined in RFC1323, buggy...\r
	371	//\r
	372	if (TCP_TIME_LT (TSVal, Tcb->TsRecent) &&\r
	373	TCP_TIME_LT (Tcb->TsRecentAge + TCP_PAWS_24DAY, mTcpTick)) {\r
	374	\r
	375	return 0;\r
	376	\r
	377	}\r
	378	\r
	379	return 1;\r
	380	}\r