[mirror_edk2.git] / NetworkPkg / TcpDxe / TcpOption.c

/** @file\r
  Routines to process TCP option.\r
\r
  Copyright (c) 2009 - 2010, Intel Corporation. All rights reserved.<BR>\r
\r
  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
**/\r
\r
#include "TcpMain.h"\r
\r
/**\r
  Get a UINT16 value from buffer.\r
\r
  @param[in] Buf              Pointer to input buffer.\r
\r
  @return                     The UINT16 value obtained from the buffer.\r
\r
**/\r
UINT16\r
TcpGetUint16 (\r
  IN UINT8 *Buf\r
  )\r
{\r
  UINT16  Value;\r
  CopyMem (&Value, Buf, sizeof (UINT16));\r
  return NTOHS (Value);\r
}\r
\r
/**\r
  Get a UINT32 value from buffer.\r
\r
  @param[in] Buf              Pointer to input buffer.\r
\r
  @return                     The UINT32 value obtained from the buffer.\r
\r
**/\r
UINT32\r
TcpGetUint32 (\r
  IN UINT8 *Buf\r
  )\r
{\r
  UINT32  Value;\r
  CopyMem (&Value, Buf, sizeof (UINT32));\r
  return NTOHL (Value);\r
}\r
\r
/**\r
  Put a UINT32 value in buffer.\r
\r
  @param[out] Buf             Pointer to the buffer.\r
  @param[in] Data             The UINT32 Date to put in the buffer.\r
\r
**/\r
VOID\r
TcpPutUint32 (\r
     OUT UINT8  *Buf,\r
  IN     UINT32 Data\r
  )\r
{\r
  Data = HTONL (Data);\r
  CopyMem (Buf, &Data, sizeof (UINT32));\r
}\r
\r
/**\r
  Compute the window scale value according to the given buffer size.\r
\r
  @param[in]  Tcb Pointer to the TCP_CB of this TCP instance.\r
\r
  @return         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 != NULL) && (Tcb->Sk != NULL));\r
\r
  BufSize = GET_RCV_BUFFSIZE (Tcb->Sk);\r
\r
  Scale   = 0;\r
  while ((Scale < TCP_OPTION_MAX_WS) && ((UINT32) (TCP_OPTION_MAX_WIN << Scale) < BufSize)) {\r
\r
    Scale++;\r
  }\r
\r
  return Scale;\r
}\r
\r
/**\r
  Build the TCP option in three-way handshake.\r
\r
  @param[in]  Tcb     Pointer to the TCP_CB of this TCP instance.\r
  @param[in]  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 != NULL) && (Nbuf != NULL) && (Nbuf->Tcp == NULL));\r
\r
  Len = 0;\r
\r
  //\r
  // Add a timestamp option if not disabled by the 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
\r
    Data = NetbufAllocSpace (\r
             Nbuf,\r
             TCP_OPTION_TS_ALIGNED_LEN,\r
             NET_BUF_HEAD\r
             );\r
\r
    ASSERT (Data != NULL);\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 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
\r
    Data = NetbufAllocSpace (\r
             Nbuf,\r
             TCP_OPTION_WS_ALIGNED_LEN,\r
             NET_BUF_HEAD\r
             );\r
\r
    ASSERT (Data != NULL);\r
\r
    Len += TCP_OPTION_WS_ALIGNED_LEN;\r
    TcpPutUint32 (Data, TCP_OPTION_WS_FAST | TcpComputeScale (Tcb));\r
  }\r
\r
  //\r
  // Build the MSS option.\r
  //\r
  Data = NetbufAllocSpace (Nbuf, TCP_OPTION_MSS_LEN, 1);\r
  ASSERT (Data != NULL);\r
\r
  Len += TCP_OPTION_MSS_LEN;\r
  TcpPutUint32 (Data, TCP_OPTION_MSS_FAST | Tcb->RcvMss);\r
\r
  return Len;\r
}\r
\r
/**\r
  Build the TCP option in synchronized states.\r
\r
  @param[in]  Tcb     Pointer to the TCP_CB of this TCP instance.\r
  @param[in]  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 != NULL) && (Nbuf != NULL) && (Nbuf->Tcp == NULL));\r
  Len = 0;\r
\r
  //\r
  // Build the 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
\r
    Data = NetbufAllocSpace (\r
            Nbuf,\r
            TCP_OPTION_TS_ALIGNED_LEN,\r
            NET_BUF_HEAD\r
            );\r
\r
    ASSERT (Data != NULL);\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
  Parse the supported options.\r
\r
  @param[in]       Tcp     Pointer to the TCP_CB of this TCP instance.\r
  @param[in, out]  Option  Pointer to the TCP_OPTION used to store the\r
                           successfully pasrsed 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 OUT TCP_OPTION *Option\r
  )\r
{\r
  UINT8 *Head;\r
  UINT8 TotalLen;\r
  UINT8 Cur;\r
  UINT8 Type;\r
  UINT8 Len;\r
\r
  ASSERT ((Tcp != NULL) && (Option != NULL));\r
\r
  Option->Flag  = 0;\r
\r
  TotalLen      = (UINT8) ((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 the timestamp option.\r
  //\r
  if ((TotalLen == TCP_OPTION_TS_ALIGNED_LEN) && (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
  // 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) || (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) || (TotalLen - Cur < TCP_OPTION_WS_LEN)) {\r
\r
        return -1;\r
      }\r
\r
      Option->WndScale = (UINT8) 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) || (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
  Check the segment against PAWS.\r
\r
  @param[in]  Tcb     Pointer to the TCP_CB of this TCP instance.\r
  @param[in]  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
\r
    return 0;\r
\r
  }\r
\r
  return 1;\r
}\r
Commit	Line	Data
a3bcde70 HT	1	/** @file\r
	2	Routines to process TCP option.\r
	3	\r
	4	Copyright (c) 2009 - 2010, Intel Corporation. All rights reserved.<BR>\r
	5	\r
	6	This program and the accompanying materials\r
	7	are licensed and made available under the terms and conditions of the BSD License\r
	8	which accompanies this distribution. The full text of the license may be found at\r
	9	http://opensource.org/licenses/bsd-license.php.\r
	10	\r
	11	THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
	12	WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
	13	\r
	14	**/\r
	15	\r
	16	#include "TcpMain.h"\r
	17	\r
	18	/**\r
	19	Get a UINT16 value from buffer.\r
	20	\r
	21	@param[in] Buf Pointer to input buffer.\r
	22	\r
	23	@return The UINT16 value obtained from the buffer.\r
	24	\r
	25	**/\r
	26	UINT16\r
	27	TcpGetUint16 (\r
	28	IN UINT8 *Buf\r
	29	)\r
	30	{\r
	31	UINT16 Value;\r
	32	CopyMem (&Value, Buf, sizeof (UINT16));\r
	33	return NTOHS (Value);\r
	34	}\r
	35	\r
	36	/**\r
	37	Get a UINT32 value from buffer.\r
	38	\r
	39	@param[in] Buf Pointer to input buffer.\r
	40	\r
	41	@return The UINT32 value obtained from the buffer.\r
	42	\r
	43	**/\r
	44	UINT32\r
	45	TcpGetUint32 (\r
	46	IN UINT8 *Buf\r
	47	)\r
	48	{\r
	49	UINT32 Value;\r
	50	CopyMem (&Value, Buf, sizeof (UINT32));\r
	51	return NTOHL (Value);\r
	52	}\r
	53	\r
	54	/**\r
	55	Put a UINT32 value in buffer.\r
	56	\r
	57	@param[out] Buf Pointer to the buffer.\r
	58	@param[in] Data The UINT32 Date to put in the buffer.\r
	59	\r
	60	**/\r
	61	VOID\r
	62	TcpPutUint32 (\r
	63	OUT UINT8 *Buf,\r
	64	IN UINT32 Data\r
65	)\r
66	{\r
67	Data = HTONL (Data);\r
68	CopyMem (Buf, &Data, sizeof (UINT32));\r
69	}\r
70	\r
71	/**\r
72	Compute the window scale value according to the given buffer size.\r
73	\r
74	@param[in] Tcb Pointer to the TCP_CB of this TCP instance.\r
75	\r
76	@return 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 != NULL) && (Tcb->Sk != NULL));\r
88	\r
89	BufSize = GET_RCV_BUFFSIZE (Tcb->Sk);\r
90	\r
91	Scale = 0;\r
92	while ((Scale < TCP_OPTION_MAX_WS) && ((UINT32) (TCP_OPTION_MAX_WIN << Scale) < BufSize)) {\r
93	\r
94	Scale++;\r
95	}\r
96	\r
97	return Scale;\r
98	}\r
99	\r
100	/**\r
101	Build the TCP option in three-way handshake.\r
102	\r
103	@param[in] Tcb Pointer to the TCP_CB of this TCP instance.\r
104	@param[in] Nbuf Pointer to the buffer to store the options.\r
105	\r
106	@return The total length of the TCP option field.\r
107	\r
108	**/\r
109	UINT16\r
110	TcpSynBuildOption (\r
111	IN TCP_CB *Tcb,\r
112	IN NET_BUF *Nbuf\r
113	)\r
114	{\r
115	UINT8 *Data;\r
116	UINT16 Len;\r
117	\r
118	ASSERT ((Tcb != NULL) && (Nbuf != NULL) && (Nbuf->Tcp == NULL));\r
119	\r
120	Len = 0;\r
121	\r
122	//\r
123	// Add a timestamp option if not disabled by the application\r
124	// and it is the first SYN segment, or the peer has sent\r
125	// us its timestamp.\r
126	//\r
127	if (!TCP_FLG_ON (Tcb->CtrlFlag, TCP_CTRL_NO_TS) &&\r
128	(!TCP_FLG_ON (TCPSEG_NETBUF (Nbuf)->Flag, TCP_FLG_ACK) \|\|\r
129	TCP_FLG_ON (Tcb->CtrlFlag, TCP_CTRL_RCVD_TS))\r
130	) {\r
131	\r
132	Data = NetbufAllocSpace (\r
133	Nbuf,\r
134	TCP_OPTION_TS_ALIGNED_LEN,\r
135	NET_BUF_HEAD\r
136	);\r
137	\r
138	ASSERT (Data != NULL);\r
139	Len += TCP_OPTION_TS_ALIGNED_LEN;\r
140	\r
141	TcpPutUint32 (Data, TCP_OPTION_TS_FAST);\r
142	TcpPutUint32 (Data + 4, mTcpTick);\r
143	TcpPutUint32 (Data + 8, 0);\r
144	}\r
145	\r
146	//\r
147	// Build window scale option, only when configured\r
148	// to send WS option, and either we are doing active\r
149	// open or we have received WS option from peer.\r
150	//\r
151	if (!TCP_FLG_ON (Tcb->CtrlFlag, TCP_CTRL_NO_WS) &&\r
152	(!TCP_FLG_ON (TCPSEG_NETBUF (Nbuf)->Flag, TCP_FLG_ACK) \|\|\r
153	TCP_FLG_ON (Tcb->CtrlFlag, TCP_CTRL_RCVD_WS))\r
154	) {\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 != NULL);\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 the MSS option.\r
170	//\r
171	Data = NetbufAllocSpace (Nbuf, TCP_OPTION_MSS_LEN, 1);\r
172	ASSERT (Data != NULL);\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	Build the TCP option in synchronized states.\r
182	\r
183	@param[in] Tcb Pointer to the TCP_CB of this TCP instance.\r
184	@param[in] Nbuf Pointer to the buffer to store the options.\r
185	\r
186	@return The total length of the TCP option field.\r
187	\r
188	**/\r
189	UINT16\r
190	TcpBuildOption (\r
191	IN TCP_CB *Tcb,\r
192	IN NET_BUF *Nbuf\r
193	)\r
194	{\r
195	UINT8 *Data;\r
196	UINT16 Len;\r
197	\r
198	ASSERT ((Tcb != NULL) && (Nbuf != NULL) && (Nbuf->Tcp == NULL));\r
199	Len = 0;\r
200	\r
201	//\r
202	// Build the Timestamp option.\r
203	//\r
204	if (TCP_FLG_ON (Tcb->CtrlFlag, TCP_CTRL_SND_TS) &&\r
205	!TCP_FLG_ON (TCPSEG_NETBUF (Nbuf)->Flag, TCP_FLG_RST)\r
206	) {\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 != NULL);\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	Parse the supported options.\r
227	\r
228	@param[in] Tcp Pointer to the TCP_CB of this TCP instance.\r
229	@param[in, out] Option Pointer to the TCP_OPTION used to store the\r
230	successfully pasrsed options.\r
231	\r
232	@retval 0 The options are successfully pasrsed.\r
233	@retval -1 Ilegal option was found.\r
234	\r
235	**/\r
236	INTN\r
237	TcpParseOption (\r
238	IN TCP_HEAD *Tcp,\r
239	IN OUT TCP_OPTION *Option\r
240	)\r
241	{\r
242	UINT8 *Head;\r
243	UINT8 TotalLen;\r
244	UINT8 Cur;\r
245	UINT8 Type;\r
246	UINT8 Len;\r
247	\r
248	ASSERT ((Tcp != NULL) && (Option != NULL));\r
249	\r
250	Option->Flag = 0;\r
251	\r
252	TotalLen = (UINT8) ((Tcp->HeadLen << 2) - sizeof (TCP_HEAD));\r
253	if (TotalLen <= 0) {\r
254	return 0;\r
255	}\r
256	\r
257	Head = (UINT8 *) (Tcp + 1);\r
258	\r
259	//\r
260	// Fast process of the timestamp option.\r
261	//\r
262	if ((TotalLen == TCP_OPTION_TS_ALIGNED_LEN) && (TcpGetUint32 (Head) == TCP_OPTION_TS_FAST)) {\r
263	\r
264	Option->TSVal = TcpGetUint32 (Head + 4);\r
265	Option->TSEcr = TcpGetUint32 (Head + 8);\r
266	Option->Flag = TCP_OPTION_RCVD_TS;\r
267	\r
268	return 0;\r
269	}\r
270	//\r
271	// Slow path to process the options.\r
272	//\r
273	Cur = 0;\r
274	\r
275	while (Cur < TotalLen) {\r
276	Type = Head[Cur];\r
277	\r
278	switch (Type) {\r
279	case TCP_OPTION_MSS:\r
280	Len = Head[Cur + 1];\r
281	\r
282	if ((Len != TCP_OPTION_MSS_LEN) \|\| (TotalLen - Cur < TCP_OPTION_MSS_LEN)) {\r
283	\r
284	return -1;\r
285	}\r
286	\r
287	Option->Mss = TcpGetUint16 (&Head[Cur + 2]);\r
288	TCP_SET_FLG (Option->Flag, TCP_OPTION_RCVD_MSS);\r
289	\r
290	Cur += TCP_OPTION_MSS_LEN;\r
291	break;\r
292	\r
293	case TCP_OPTION_WS:\r
294	Len = Head[Cur + 1];\r
295	\r
296	if ((Len != TCP_OPTION_WS_LEN) \|\| (TotalLen - Cur < TCP_OPTION_WS_LEN)) {\r
297	\r
298	return -1;\r
299	}\r
300	\r
301	Option->WndScale = (UINT8) MIN (14, Head[Cur + 2]);\r
302	TCP_SET_FLG (Option->Flag, TCP_OPTION_RCVD_WS);\r
303	\r
304	Cur += TCP_OPTION_WS_LEN;\r
305	break;\r
306	\r
307	case TCP_OPTION_TS:\r
308	Len = Head[Cur + 1];\r
309	\r
310	if ((Len != TCP_OPTION_TS_LEN) \|\| (TotalLen - Cur < TCP_OPTION_TS_LEN)) {\r
311	\r
312	return -1;\r
313	}\r
314	\r
315	Option->TSVal = TcpGetUint32 (&Head[Cur + 2]);\r
316	Option->TSEcr = TcpGetUint32 (&Head[Cur + 6]);\r
317	TCP_SET_FLG (Option->Flag, TCP_OPTION_RCVD_TS);\r
318	\r
319	Cur += TCP_OPTION_TS_LEN;\r
320	break;\r
321	\r
322	case TCP_OPTION_NOP:\r
323	Cur++;\r
324	break;\r
325	\r
326	case TCP_OPTION_EOP:\r
327	Cur = TotalLen;\r
328	break;\r
329	\r
330	default:\r
331	Len = Head[Cur + 1];\r
332	\r
333	if ((TotalLen - Cur) < Len \|\| Len < 2) {\r
334	return -1;\r
335	}\r
336	\r
337	Cur = (UINT8) (Cur + Len);\r
338	break;\r
339	}\r
340	\r
341	}\r
342	\r
343	return 0;\r
344	}\r
345	\r
346	/**\r
347	Check the segment against PAWS.\r
348	\r
349	@param[in] Tcb Pointer to the TCP_CB of this TCP instance.\r
350	@param[in] TSVal The timestamp value.\r
351	\r
352	@retval 1 The segment passed the PAWS check.\r
353	@retval 0 The segment failed to pass the PAWS check.\r
354	\r
355	**/\r
356	UINT32\r
357	TcpPawsOK (\r
358	IN TCP_CB *Tcb,\r
359	IN UINT32 TSVal\r
360	)\r
361	{\r
362	//\r
363	// PAWS as defined in RFC1323, buggy...\r
364	//\r
365	if (TCP_TIME_LT (TSVal, Tcb->TsRecent) &&\r
366	TCP_TIME_LT (Tcb->TsRecentAge + TCP_PAWS_24DAY, mTcpTick)\r
367	) {\r
368	\r
369	return 0;\r
370	\r
371	}\r
372	\r
373	return 1;\r
374	}\r