3 Copyright (C) Dean Camera, 2012.
5 dean [at] fourwalledcubicle [dot] com
10 Copyright 2012 Dean Camera (dean [at] fourwalledcubicle [dot] com)
12 Permission to use, copy, modify, distribute, and sell this
13 software and its documentation for any purpose is hereby granted
14 without fee, provided that the above copyright notice appear in
15 all copies and that both that the copyright notice and this
16 permission notice and warranty disclaimer appear in supporting
17 documentation, and that the name of the author not be used in
18 advertising or publicity pertaining to distribution of the
19 software without specific, written prior permission.
21 The author disclaim all warranties with regard to this
22 software, including all implied warranties of merchantability
23 and fitness. In no event shall the author be liable for any
24 special, indirect or consequential damages or any damages
25 whatsoever resulting from loss of use, data or profits, whether
26 in an action of contract, negligence or other tortious action,
27 arising out of or in connection with the use or performance of
33 * Header file for TCP.c.
43 #include "EthernetProtocols.h"
45 #include "ProtocolDecoders.h"
48 /** Maximum number of TCP ports which can be open at the one time. */
49 #define MAX_OPEN_TCP_PORTS 1
51 /** Maximum number of TCP connections which can be sustained at the one time. */
52 #define MAX_TCP_CONNECTIONS 3
54 /** TCP window size, giving the maximum number of bytes which can be buffered at the one time. */
55 #define TCP_WINDOW_SIZE 512
57 /** Port number for HTTP transmissions. */
58 #define TCP_PORT_HTTP SwapEndian_16(80)
60 /** Data direction indicator for a TCP application buffer, indicating data from host-to-device. */
61 #define TCP_PACKETDIR_IN false
63 /** Data direction indicator for a TCP application buffer, indicating data from device-to-host. */
64 #define TCP_PACKETDIR_OUT true
66 /** Congestion Window Reduced TCP flag mask. */
67 #define TCP_FLAG_CWR (1 << 7)
69 /** Explicit Congestion Notification TCP flag mask. */
70 #define TCP_FLAG_ECE (1 << 6)
72 /** Urgent TCP flag mask. */
73 #define TCP_FLAG_URG (1 << 5)
75 /** Data Acknowledge TCP flag mask. */
76 #define TCP_FLAG_ACK (1 << 4)
78 /** Data Push TCP flag mask. */
79 #define TCP_FLAG_PSH (1 << 3)
81 /** Reset TCP flag mask. */
82 #define TCP_FLAG_RST (1 << 2)
84 /** Synchronize TCP flag mask. */
85 #define TCP_FLAG_SYN (1 << 1)
87 /** Connection Finalize TCP flag mask. */
88 #define TCP_FLAG_FIN (1 << 0)
90 /** Application macro: Determines if the given application buffer contains a packet received from the host
92 * \param[in] Buffer Application buffer to check
94 * \return Boolean true if the buffer contains a packet from the host, false otherwise
96 #define TCP_APP_HAS_RECEIVED_PACKET(Buffer) (Buffer->Ready && (Buffer->Direction == TCP_PACKETDIR_IN))
98 /** Application macro: Indicates if the application buffer is currently locked by the application for device-to-host transfers.
100 * \param[in] Buffer Application buffer to check
102 * \return Boolean true if the buffer has been captured by the application for device-to-host transmissions, false otherwise
104 #define TCP_APP_HAVE_CAPTURED_BUFFER(Buffer) (!(Buffer->Ready) && Buffer->InUse && \
105 (Buffer->Direction == TCP_PACKETDIR_OUT))
107 /** Application macro: Indicates if the application can lock the buffer for multiple continued device-to-host transmissions.
109 * \param[in] Buffer Application buffer to check
111 * \return Boolean true if the buffer may be captured by the application for device-to-host transmissions, false otherwise
113 #define TCP_APP_CAN_CAPTURE_BUFFER(Buffer) Buffer->InUse
115 /** Application macro: Captures the application buffer, locking it for device-to-host transmissions only. This should be
116 * performed when the application needs to transmit several packets worth of data in succession with no interruptions from the host.
118 * \pre The application must check that the buffer can be locked first using TCP_APP_CAN_CAPTURE_BUFFER().
120 * \param[in] Buffer Application buffer to lock
122 #define TCP_APP_CAPTURE_BUFFER(Buffer) MACROS{ Buffer->Direction = TCP_PACKETDIR_OUT; Buffer->InUse = true; }MACROE
124 /** Application macro: Releases a captured application buffer, allowing for host-to-device packets to be received.
126 * \param[in] Buffer Application buffer to release
128 #define TCP_APP_RELEASE_BUFFER(Buffer) MACROS{ Buffer->InUse = false; }MACROE
130 /** Application macro: Sends the contents of the given application buffer to the host.
132 * \param[in] Buffer Application buffer to send
133 * \param[in] Len Length of data contained in the buffer
135 #define TCP_APP_SEND_BUFFER(Buffer, Len) MACROS{ Buffer->Direction = TCP_PACKETDIR_OUT; Buffer->Length = Len; Buffer->Ready = true; }MACROE
137 /** Application macro: Clears the application buffer, ready for a packet to be written to it.
139 * \param[in] Buffer Application buffer to clear
141 #define TCP_APP_CLEAR_BUFFER(Buffer) MACROS{ Buffer->Ready = false; Buffer->Length = 0; }MACROE
143 /** Application macro: Closes an open connection to a host.
145 * \param[in] Connection Open TCP connection to close
147 #define TCP_APP_CLOSECONNECTION(Connection) MACROS{ Connection->State = TCP_Connection_Closing; }MACROE
150 /** Enum for possible TCP port states. */
151 enum TCP_PortStates_t
153 TCP_Port_Closed
= 0, /**< TCP port closed, no connections to a host may be made on this port. */
154 TCP_Port_Open
= 1, /**< TCP port open, connections to a host may be made on this port. */
157 /** Enum for possible TCP connection states. */
158 enum TCP_ConnectionStates_t
160 TCP_Connection_Listen
= 0, /**< Listening for a connection from a host */
161 TCP_Connection_SYNSent
= 1, /**< Unused */
162 TCP_Connection_SYNReceived
= 2, /**< SYN received, waiting for ACK */
163 TCP_Connection_Established
= 3, /**< Connection established in both directions */
164 TCP_Connection_FINWait1
= 4, /**< Closing, waiting for ACK */
165 TCP_Connection_FINWait2
= 5, /**< Closing, waiting for FIN ACK */
166 TCP_Connection_CloseWait
= 6, /**< Closing, waiting for ACK */
167 TCP_Connection_Closing
= 7, /**< Unused */
168 TCP_Connection_LastACK
= 8, /**< Unused */
169 TCP_Connection_TimeWait
= 9, /**< Unused */
170 TCP_Connection_Closed
= 10, /**< Connection closed in both directions */
174 /** Type define for a TCP connection buffer structure, including size, data and direction. */
177 uint16_t Length
; /**< Length of data in the TCP application buffer */
178 uint8_t Data
[TCP_WINDOW_SIZE
]; /**< TCP application data buffer */
179 bool Direction
; /**< Buffer transmission direction, either TCP_PACKETDIR_IN or TCP_PACKETDIR_OUT */
180 bool Ready
; /**< If data from host, indicates buffer ready to be read, otherwise indicates
181 * buffer ready to be sent to the host
183 bool InUse
; /**< Indicates if the buffer is locked to to the current direction, and cannot be changed */
184 } TCP_ConnectionBuffer_t
;
186 /** Type define for a TCP connection information structure. */
189 uint32_t SequenceNumberIn
; /**< Current TCP sequence number for host-to-device */
190 uint32_t SequenceNumberOut
; /**< Current TCP sequence number for device-to-host */
191 TCP_ConnectionBuffer_t Buffer
; /**< Connection application data buffer */
192 } TCP_ConnectionInfo_t
;
194 /** Type define for a complete TCP connection state. */
197 uint16_t Port
; /**< Connection port number on the device */
198 uint16_t RemotePort
; /**< Connection port number on the host */
199 IP_Address_t RemoteAddress
; /**< Connection protocol IP address of the host */
200 TCP_ConnectionInfo_t Info
; /**< Connection information, including application buffer */
201 uint8_t State
; /**< Current connection state, a value from the \ref TCP_ConnectionStates_t enum */
202 } TCP_ConnectionState_t
;
204 /** Type define for a TCP port state. */
207 uint16_t Port
; /**< TCP port number on the device */
208 uint8_t State
; /**< Current port state, a value from the \ref TCP_PortStates_t enum */
209 void (*ApplicationHandler
) (TCP_ConnectionState_t
* ConnectionState
,
210 TCP_ConnectionBuffer_t
* Buffer
); /**< Port application handler */
213 /** Type define for a TCP packet header. */
216 uint16_t SourcePort
; /**< Source port of the TCP packet */
217 uint16_t DestinationPort
; /**< Destination port of the TCP packet */
219 uint32_t SequenceNumber
; /**< Data sequence number of the packet */
220 uint32_t AcknowledgmentNumber
; /**< Data acknowledgment number of the packet */
222 unsigned Reserved
: 4; /**< Reserved, must be all 0 */
223 unsigned DataOffset
: 4; /**< Offset of the data from the start of the header, in 4 byte chunks */
224 uint8_t Flags
; /**< TCP packet flags */
225 uint16_t WindowSize
; /**< Current data window size (bytes remaining in reception buffer) */
227 uint16_t Checksum
; /**< TCP checksum */
228 uint16_t UrgentPointer
; /**< Urgent data pointer */
231 /* Function Prototypes: */
234 bool TCP_SetPortState(const uint16_t Port
,
236 void (*Handler
)(TCP_ConnectionState_t
*, TCP_ConnectionBuffer_t
*));
237 uint8_t TCP_GetPortState(const uint16_t Port
);
238 bool TCP_SetConnectionState(const uint16_t Port
,
239 const IP_Address_t RemoteAddress
,
240 const uint16_t RemotePort
,
241 const uint8_t State
);
242 uint8_t TCP_GetConnectionState(const uint16_t Port
,
243 const IP_Address_t RemoteAddress
,
244 const uint16_t RemotePort
);
245 TCP_ConnectionInfo_t
* TCP_GetConnectionInfo(const uint16_t Port
,
246 const IP_Address_t RemoteAddress
,
247 const uint16_t RemotePort
);
248 int16_t TCP_ProcessTCPPacket(void* IPHeaderInStart
,
249 void* TCPHeaderInStart
,
250 void* TCPHeaderOutStart
);
252 #if defined(INCLUDE_FROM_TCP_C)
253 static uint16_t TCP_Checksum16(void* TCPHeaderOutStart
,
254 const IP_Address_t SourceAddress
,
255 const IP_Address_t DestinationAddress
,
256 uint16_t TCPOutSize
);