audk/NetworkPkg/TcpDxe/TcpOption.h

124 lines
3.6 KiB
C

/** @file
Tcp option's routine header file.
Copyright (c) 2009 - 2018, Intel Corporation. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#ifndef _TCP_OPTION_H_
#define _TCP_OPTION_H_
//
// Supported TCP option types and their length.
//
#define TCP_OPTION_EOP 0 ///< End Of oPtion
#define TCP_OPTION_NOP 1 ///< No-Option.
#define TCP_OPTION_MSS 2 ///< Maximum Segment Size
#define TCP_OPTION_WS 3 ///< Window scale
#define TCP_OPTION_TS 8 ///< Timestamp
#define TCP_OPTION_MSS_LEN 4 ///< Length of MSS option
#define TCP_OPTION_WS_LEN 3 ///< Length of window scale option
#define TCP_OPTION_TS_LEN 10 ///< Length of timestamp option
#define TCP_OPTION_WS_ALIGNED_LEN 4 ///< Length of window scale option, aligned
#define TCP_OPTION_TS_ALIGNED_LEN 12 ///< Length of timestamp option, aligned
//
// recommend format of timestamp window scale
// option for fast process.
//
#define TCP_OPTION_TS_FAST ((TCP_OPTION_NOP << 24) |\
(TCP_OPTION_NOP << 16) | \
(TCP_OPTION_TS << 8) | \
(TCP_OPTION_TS_LEN))
#define TCP_OPTION_WS_FAST ((TCP_OPTION_NOP << 24) | \
(TCP_OPTION_WS << 16) | \
(TCP_OPTION_WS_LEN << 8))
#define TCP_OPTION_MSS_FAST ((TCP_OPTION_MSS << 24) | (TCP_OPTION_MSS_LEN << 16))
//
// Other misc definitions
//
#define TCP_OPTION_RCVD_MSS 0x01
#define TCP_OPTION_RCVD_WS 0x02
#define TCP_OPTION_RCVD_TS 0x04
#define TCP_OPTION_MAX_WS 14 ///< Maximum window scale value
#define TCP_OPTION_MAX_WIN 0xffff ///< Max window size in TCP header
///
/// The structure to store the parse option value.
/// ParseOption only parses the options, doesn't process them.
///
typedef struct _TCP_OPTION {
UINT8 Flag; ///< Flag such as TCP_OPTION_RCVD_MSS
UINT8 WndScale; ///< The WndScale received
UINT16 Mss; ///< The Mss received
UINT32 TSVal; ///< The TSVal field in a timestamp option
UINT32 TSEcr; ///< The TSEcr field in a timestamp option
} TCP_OPTION;
/**
Compute the window scale value according to the given buffer size.
@param[in] Tcb Pointer to the TCP_CB of this TCP instance.
@return The scale value.
**/
UINT8
TcpComputeScale (
IN TCP_CB *Tcb
);
/**
Build the TCP option in three-way handshake.
@param[in] Tcb Pointer to the TCP_CB of this TCP instance.
@param[in] Nbuf Pointer to the buffer to store the options.
@return The total length of the TCP option field.
**/
UINT16
TcpSynBuildOption (
IN TCP_CB *Tcb,
IN NET_BUF *Nbuf
);
/**
Build the TCP option in synchronized states.
@param[in] Tcb Pointer to the TCP_CB of this TCP instance.
@param[in] Nbuf Pointer to the buffer to store the options.
@return The total length of the TCP option field.
**/
UINT16
TcpBuildOption (
IN TCP_CB *Tcb,
IN NET_BUF *Nbuf
);
/**
Parse the supported options.
@param[in] Tcp Pointer to the TCP_CB of this TCP instance.
@param[in, out] Option Pointer to the TCP_OPTION used to store the
successfully pasrsed options.
@retval 0 The options successfully pasrsed.
@retval -1 Illegal option was found.
**/
INTN
TcpParseOption (
IN TCP_HEAD *Tcp,
IN OUT TCP_OPTION *Option
);
#endif