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/*********************************************************************
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*
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* UDP Module for Microchip TCP/IP Stack
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*
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*********************************************************************
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* FileName: UDP.c
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* Dependencies: StackTsk.h
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* MAC.h
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* Processor: PIC18
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* Complier: MCC18 v1.00.50 or higher
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* HITECH PICC-18 V8.10PL1 or higher
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* Company: Microchip Technology, Inc.
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*
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* Software License Agreement
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*
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* The software supplied herewith by Microchip Technology Incorporated
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* (the “Company”) for its PICmicro® Microcontroller is intended and
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* supplied to you, the Company’s customer, for use solely and
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* exclusively on Microchip PICmicro Microcontroller products. The
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* software is owned by the Company and/or its supplier, and is
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* protected under applicable copyright laws. All rights are reserved.
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* Any use in violation of the foregoing restrictions may subject the
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* user to criminal sanctions under applicable laws, as well as to
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* civil liability for the breach of the terms and conditions of this
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* license.
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*
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* THIS SOFTWARE IS PROVIDED IN AN “AS IS” CONDITION. NO WARRANTIES,
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* WHETHER EXPRESS, IMPLIED OR STATUTORY, INCLUDING, BUT NOT LIMITED
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* TO, IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
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* PARTICULAR PURPOSE APPLY TO THIS SOFTWARE. THE COMPANY SHALL NOT,
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* IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL OR
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* CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER.
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*
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*
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* HiTech PICC18 Compiler Options excluding device selection:
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* -FAKELOCAL -G -O -Zg -E -C
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*
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* Author Date Comment
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*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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* Nilesh Rajbharti 3/19/01 Original (Rev 1.0)
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* Nilesh Rajbharti 2/26/03 Fixed UDPGet and UDPProcess bugs
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* as discovered and fixed by John Owen
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* of Powerwave.
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* 1. UDPGet would return FALSE on last good byte
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* 2. UDPProcess was incorrectly calculating length.
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* Nilesh Rajbharti 5/19/03 Added bFirstRead flag similar to TCP
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* to detect very first UDPGet and
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* reset MAC Rx pointer to begining of
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* UDP data area. This would ensure that
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* if UDP socket has pending Rx data and
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* another module resets MAC Rx pointer,
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* next UDP socket Get would get correct
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* data.
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* Robert Sloan (RSS) 5/29/03 Improved FindMatchingSocket()
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********************************************************************/
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#define THIS_IS_UDP_MODULE
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#include <string.h>
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#include "stacktsk.h"
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#include "helpers.h"
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#include "mac.h"
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#include "ip.h"
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#include "udp.h"
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#if !defined(STACK_USE_UDP)
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#error UDP module is not enabled.
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#error If you do not want UDP module, remove this file from your
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#error project to reduce your code size.
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#error If you do want UDP module, make sure that STACK_USE_UDP
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#error is defined in StackTsk.h file.
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#endif
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UDP_SOCKET_INFO UDPSocketInfo[MAX_UDP_SOCKETS];
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UDP_SOCKET activeUDPSocket;
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static UDP_SOCKET FindMatchingSocket(UDP_HEADER *h, NODE_INFO *remoteNode);
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/*********************************************************************
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* Function: void UDPInit(void)
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*
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* PreCondition: None
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*
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* Input: None
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*
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* Output: None
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*
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* Side Effects: None
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*
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* Overview: Initializes internal variables.
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*
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* Note:
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********************************************************************/
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void UDPInit(void)
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{
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UDP_SOCKET s;
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for ( s = 0; s < MAX_UDP_SOCKETS; s++ )
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{
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UDPSocketInfo[s].localPort = INVALID_UDP_PORT;
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UDPSocketInfo[s].Flags.bFirstRead = FALSE;
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}
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}
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/*********************************************************************
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* Function: UDP_SOCKET UDPOpen(UDP_PORT localPort,
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* NODE_INFO *remoteNode,
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* UDP_PORT remotePort)
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*
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* PreCondition: UDPInit() is already called
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*
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* Input: remoteNode - Remote Node info such as MAC and IP
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* address
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* If NULL, broadcast node address is set.
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* remotePort - Remote Port to which to talk to
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* If INVALID_UDP_SOCKET, localPort is
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* opened for Listen.
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* localPort - A valid port number.
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*
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* Output: A valid UDP socket that is to be used for
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* subsequent UDP communications.
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*
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* Side Effects: None
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*
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* Overview: A UDP packet header is assembled and loaded into
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* UDP transmit buffer.
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*
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* Note: This call must always have valid localPort
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* value.
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********************************************************************/
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UDP_SOCKET UDPOpen(UDP_PORT localPort,
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NODE_INFO *remoteNode,
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UDP_PORT remotePort)
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{
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UDP_SOCKET s;
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UDP_SOCKET_INFO *p;
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p = UDPSocketInfo;
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for ( s = 0; s < MAX_UDP_SOCKETS; s++ )
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{
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if ( p->localPort == INVALID_UDP_PORT )
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{
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p->localPort = localPort;
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/*
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* If remoteNode is supplied, remember it.
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*/
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if ( remoteNode )
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{
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memcpy((void*)&p->remoteNode,
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(const void*)remoteNode,
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sizeof(p->remoteNode));
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}
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/* else Set broadcast address - TO BE DONE */
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p->remotePort = remotePort;
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p->TxCount = 0;
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p->RxCount = 0;
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/*
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* Mark this socket as active.
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* Once an active socket is set, subsequent operation can be
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* done without explicitely supply socket identifier.
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*/
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activeUDPSocket = s;
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return s;
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}
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p++;
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}
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return (UDP_SOCKET)INVALID_UDP_SOCKET;
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}
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/*********************************************************************
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* Function: void UDPClose(UDP_SOCKET s)
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*
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* PreCondition: UDPOpen() is already called
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*
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* Input: s - Socket that is to be closed.
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*
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* Output: None
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*
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* Side Effects: None
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*
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* Overview: Given socket is marked as available for future
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* new communcations.
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*
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* Note: This function does not affect previous
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* active UDP socket designation.
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********************************************************************/
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void UDPClose(UDP_SOCKET s)
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{
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UDPSocketInfo[s].localPort = INVALID_UDP_PORT;
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}
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/*********************************************************************
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* Function: BOOL UDPPut(BYTE v)
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*
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* PreCondition: UDPIsPutReady() == TRUE with desired UDP socket
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* that is to be loaded.
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*
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* Input: v - Data byte to loaded into transmit buffer
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*
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* Output: TRUE if transmit buffer is still ready to accept
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* more data bytes
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*
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* FALSE if transmit buffer can no longer accept
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* any more data byte.
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*
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* Side Effects: None
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*
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* Overview: Given data byte is put into UDP transmit buffer
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* and active UDP socket buffer length is incremented
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* by one.
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* If buffer has become full, FALSE is returned.
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* Or else TRUE is returned.
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*
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* Note: This function loads data into an active UDP socket
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* as determined by previous call to UDPIsPutReady()
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********************************************************************/
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BOOL UDPPut(BYTE v)
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{
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UDP_SOCKET_INFO *p;
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WORD temp;
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p = &UDPSocketInfo[activeUDPSocket];
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if ( p->TxCount == 0 )
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{
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/*
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* This is the very first byte that is loaded in UDP buffer.
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* Remember what transmit buffer we are loading, and
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* start loading this and next bytes in data area of UDP
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* packet.
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*/
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p->TxBuffer = MACGetTxBuffer();
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IPSetTxBuffer(p->TxBuffer, sizeof(UDP_HEADER));
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p->TxOffset = 0;
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}
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/*
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* Load it.
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*/
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MACPut(v);
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if ( p->TxOffset++ >= p->TxCount )
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p->TxCount++;
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#if 0
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/*
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* Keep track of number of bytes loaded.
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* If total bytes fill up buffer, transmit it.
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*/
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p->TxCount++;
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#endif
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#define SIZEOF_MAC_HEADER (14)
|
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/*
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* Depending on what communication media is used, allowable UDP
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* data length will vary.
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*/
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#if !defined(STACK_USE_SLIP)
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#define MAX_UDP_DATA (MAC_TX_BUFFER_SIZE - SIZEOF_MAC_HEADER - sizeof(IP_HEADER) - sizeof(UDP_HEADER))
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#else
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#define MAX_UDP_DATA (MAC_TX_BUFFER_SIZE - sizeof(IP_HEADER) - sizeof(UDP_HEADER) )
|
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#endif
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temp = p->TxCount;
|
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if ( temp >= MAX_UDP_DATA )
|
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{
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UDPFlush();
|
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}
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#undef MAX_UDP_DATA
|
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return TRUE;
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}
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|
| 289 |
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| 290 |
/*********************************************************************
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* Function: BOOL UDPFlush(void)
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*
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* PreCondition: UDPPut() is already called and desired UDP socket
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* is set as an active socket by calling
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* UDPIsPutReady().
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*
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| 297 |
* Input: None
|
| 298 |
*
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| 299 |
* Output: All and any data associated with active UDP socket
|
| 300 |
* buffer is marked as ready for transmission.
|
| 301 |
*
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| 302 |
* Side Effects: None
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*
|
| 304 |
* Overview: None
|
| 305 |
*
|
| 306 |
* Note: This function transmit all data from
|
| 307 |
* an active UDP socket.
|
| 308 |
********************************************************************/
|
| 309 |
void UDPFlush(void)
|
| 310 |
{
|
| 311 |
UDP_HEADER h;
|
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UDP_SOCKET_INFO *p;
|
| 313 |
|
| 314 |
/*
|
| 315 |
* When using SLIP (USART), packet transmission takes some time
|
| 316 |
* and hence before sending another packet, we must make sure
|
| 317 |
* that, last packet is transmitted.
|
| 318 |
* When using ethernet controller, transmission occurs very fast
|
| 319 |
* and by the time next packet is transmitted, previous is
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* transmitted and we do not need to check for last packet.
|
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*/
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//while( !IPIsTxReady() );
|
| 323 |
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p = &UDPSocketInfo[activeUDPSocket];
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h.SourcePort = swaps(p->localPort);
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h.DestinationPort = swaps(p->remotePort);
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| 328 |
h.Length = (WORD)((WORD)p->TxCount + (WORD)sizeof(UDP_HEADER));
|
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// Do not swap h.Length yet. It is needed in IPPutHeader.
|
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h.Checksum = 0x00;
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|
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IPSetTxBuffer(p->TxBuffer, 0);
|
| 333 |
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| 334 |
/*
|
| 335 |
* Load IP header.
|
| 336 |
*/
|
| 337 |
IPPutHeader( &p->remoteNode,
|
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IP_PROT_UDP,
|
| 339 |
h.Length );
|
| 340 |
|
| 341 |
|
| 342 |
// Now swap h.Length.
|
| 343 |
h.Length = swaps(h.Length);
|
| 344 |
|
| 345 |
/*
|
| 346 |
* Now load UDP header.
|
| 347 |
*/
|
| 348 |
IPPutArray((BYTE*)&h, sizeof(h));
|
| 349 |
|
| 350 |
/*
|
| 351 |
* Update checksum.
|
| 352 |
* TO BE IMPLEMENTED
|
| 353 |
*/
|
| 354 |
|
| 355 |
MACFlush();
|
| 356 |
|
| 357 |
p->TxBuffer = INVALID_BUFFER;
|
| 358 |
p->TxCount = 0;
|
| 359 |
|
| 360 |
}
|
| 361 |
|
| 362 |
|
| 363 |
|
| 364 |
/*********************************************************************
|
| 365 |
* Function: BOOL UDPIsGetReady(UDP_SOCKET s)
|
| 366 |
*
|
| 367 |
* PreCondition: UDPInit() is already called.
|
| 368 |
*
|
| 369 |
* Input: A valid UDP socket that is already "Listen"ed on
|
| 370 |
* or opened.
|
| 371 |
*
|
| 372 |
* Output: TRUE if given port contains any data.
|
| 373 |
* FALSE if given port does not contain any data.
|
| 374 |
*
|
| 375 |
* Side Effects: Given socket is set as an active UDP Socket.
|
| 376 |
*
|
| 377 |
* Overview: None
|
| 378 |
*
|
| 379 |
* Note: This function automatically sets supplied socket
|
| 380 |
* as an active socket. Caller need not call
|
| 381 |
* explicit function UDPSetActiveSocket(). All
|
| 382 |
* subsequent calls will us this socket as an
|
| 383 |
* active socket.
|
| 384 |
********************************************************************/
|
| 385 |
BOOL UDPIsGetReady(UDP_SOCKET s)
|
| 386 |
{
|
| 387 |
activeUDPSocket = s;
|
| 388 |
return ( UDPSocketInfo[activeUDPSocket].RxCount > 0 );
|
| 389 |
}
|
| 390 |
|
| 391 |
/*********************************************************************
|
| 392 |
* Function: BOOL UDPGet(BYTE *v)
|
| 393 |
*
|
| 394 |
* PreCondition: UDPInit() is already called AND
|
| 395 |
* UDPIsGetReady(s) == TRUE
|
| 396 |
*
|
| 397 |
* Input: v - Buffer to receive UDP data byte
|
| 398 |
*
|
| 399 |
* Output: TRUE if a data byte was read
|
| 400 |
* FALSE if no data byte was read or available
|
| 401 |
*
|
| 402 |
* Side Effects: None
|
| 403 |
*
|
| 404 |
* Overview: None
|
| 405 |
*
|
| 406 |
* Note: This function fetches data from an active UDP
|
| 407 |
* socket as set by UDPIsGetReady() call.
|
| 408 |
********************************************************************/
|
| 409 |
BOOL UDPGet(BYTE *v)
|
| 410 |
{
|
| 411 |
/*
|
| 412 |
* CALLER MUST MAKE SURE THAT THERE IS ENOUGH DATA BYTE IN BUFFER
|
| 413 |
* BEFORE CALLING THIS FUNCTION.
|
| 414 |
* USE UDPIsGetReady() TO CONFIRM.
|
| 415 |
*/
|
| 416 |
if ( UDPSocketInfo[activeUDPSocket].RxCount == 0 )
|
| 417 |
return FALSE;
|
| 418 |
|
| 419 |
// If if this very first read to packet, set MAC Rx Pointer to
|
| 420 |
// beginig of UDP data area.
|
| 421 |
if ( UDPSocketInfo[activeUDPSocket].Flags.bFirstRead )
|
| 422 |
{
|
| 423 |
UDPSocketInfo[activeUDPSocket].Flags.bFirstRead = FALSE;
|
| 424 |
UDPSetRxBuffer(0);
|
| 425 |
}
|
| 426 |
|
| 427 |
*v = MACGet();
|
| 428 |
|
| 429 |
UDPSocketInfo[activeUDPSocket].RxCount--;
|
| 430 |
|
| 431 |
if ( UDPSocketInfo[activeUDPSocket].RxCount == 0 )
|
| 432 |
{
|
| 433 |
MACDiscardRx();
|
| 434 |
}
|
| 435 |
|
| 436 |
return TRUE;
|
| 437 |
}
|
| 438 |
|
| 439 |
|
| 440 |
/*********************************************************************
|
| 441 |
* Function: void UDPDiscard(void)
|
| 442 |
*
|
| 443 |
* PreCondition: UDPInit() is already called AND
|
| 444 |
* UDPIsGetReady() == TRUE with desired UDP socket.
|
| 445 |
*
|
| 446 |
* Input: None
|
| 447 |
*
|
| 448 |
* Output: None
|
| 449 |
*
|
| 450 |
* Side Effects: None
|
| 451 |
*
|
| 452 |
* Overview: None
|
| 453 |
*
|
| 454 |
* Note: This function discards an active UDP socket content.
|
| 455 |
********************************************************************/
|
| 456 |
void UDPDiscard(void)
|
| 457 |
{
|
| 458 |
if ( UDPSocketInfo[activeUDPSocket].RxCount )
|
| 459 |
MACDiscardRx();
|
| 460 |
|
| 461 |
UDPSocketInfo[activeUDPSocket].RxCount = 0;
|
| 462 |
}
|
| 463 |
|
| 464 |
|
| 465 |
|
| 466 |
/*********************************************************************
|
| 467 |
* Function: BOOL UDPProcess(NODE_INFO* remoteNode,
|
| 468 |
* WORD len)
|
| 469 |
*
|
| 470 |
* PreCondition: UDPInit() is already called AND
|
| 471 |
* UDP segment is ready in MAC buffer
|
| 472 |
*
|
| 473 |
* Input: remoteNode - Remote node info
|
| 474 |
* len - Total length of UDP semgent.
|
| 475 |
*
|
| 476 |
* Output: TRUE if this function has completed its task
|
| 477 |
* FALSE otherwise
|
| 478 |
*
|
| 479 |
* Side Effects: None
|
| 480 |
*
|
| 481 |
* Overview: None
|
| 482 |
*
|
| 483 |
* Note: None
|
| 484 |
********************************************************************/
|
| 485 |
BOOL UDPProcess(NODE_INFO *remoteNode, WORD len)
|
| 486 |
{
|
| 487 |
UDP_HEADER h;
|
| 488 |
UDP_SOCKET s;
|
| 489 |
|
| 490 |
/*
|
| 491 |
* Retrieve UDP header.
|
| 492 |
*/
|
| 493 |
MACGetArray((BYTE*)&h, sizeof(h));
|
| 494 |
|
| 495 |
h.SourcePort = swaps(h.SourcePort);
|
| 496 |
h.DestinationPort = swaps(h.DestinationPort);
|
| 497 |
h.Length = swaps(h.Length) - sizeof(UDP_HEADER);;
|
| 498 |
h.Checksum = swaps(h.Checksum);
|
| 499 |
|
| 500 |
s = FindMatchingSocket(&h, remoteNode);
|
| 501 |
if ( s == INVALID_UDP_SOCKET )
|
| 502 |
{
|
| 503 |
/*
|
| 504 |
* If there is no matching socket, There is no one to handle
|
| 505 |
* this data. Discard it.
|
| 506 |
*/
|
| 507 |
MACDiscardRx();
|
| 508 |
}
|
| 509 |
else
|
| 510 |
{
|
| 511 |
UDPSocketInfo[s].RxCount = h.Length;
|
| 512 |
UDPSocketInfo[s].Flags.bFirstRead = TRUE;
|
| 513 |
}
|
| 514 |
|
| 515 |
|
| 516 |
return TRUE;
|
| 517 |
}
|
| 518 |
|
| 519 |
|
| 520 |
/*********************************************************************
|
| 521 |
* Function: UDP_SOCKET FindMatchingSocket(UDP_HEADER *h,
|
| 522 |
* NODE_INFO *remoteNode)
|
| 523 |
*
|
| 524 |
* PreCondition: UDP Segment header has been retrieved from buffer
|
| 525 |
* The IP header has also been retrieved
|
| 526 |
*
|
| 527 |
* Input: remoteNode - Remote node info from IP header
|
| 528 |
* h - header of UDP semgent.
|
| 529 |
*
|
| 530 |
* Output: matching UDP socket or INVALID_UDP_SOCKET
|
| 531 |
*
|
| 532 |
* Side Effects: None
|
| 533 |
*
|
| 534 |
* Overview: None
|
| 535 |
*
|
| 536 |
* Note: None
|
| 537 |
********************************************************************/
|
| 538 |
#define BROADCAST_ADDRESS (0xffffffffL)
|
| 539 |
static UDP_SOCKET FindMatchingSocket(UDP_HEADER *h, NODE_INFO *remoteNode)
|
| 540 |
{
|
| 541 |
UDP_SOCKET s;
|
| 542 |
UDP_SOCKET partialMatch;
|
| 543 |
UDP_SOCKET_INFO *p;
|
| 544 |
|
| 545 |
partialMatch = INVALID_UDP_SOCKET;
|
| 546 |
|
| 547 |
p = UDPSocketInfo;
|
| 548 |
for ( s = 0; s < MAX_UDP_SOCKETS; s++ )
|
| 549 |
{
|
| 550 |
/*
|
| 551 |
* This packet is said to be matching with current socket
|
| 552 |
* 1. If its destination port matches with our local port.
|
| 553 |
* 2. This socket does not have any data pending.
|
| 554 |
* 3. Packet source IP address matches with socket remote IP address.
|
| 555 |
* OR this socket had transmitted packet with destination address
|
| 556 |
* as broadcast.
|
| 557 |
*/
|
| 558 |
if ( p->localPort == h->DestinationPort )
|
| 559 |
{
|
| 560 |
if ( (p->remotePort == h->SourcePort) && (p->RxCount == 0L) )
|
| 561 |
{
|
| 562 |
if ( (p->remoteNode.IPAddr.Val == remoteNode->IPAddr.Val) ||
|
| 563 |
(p->remoteNode.IPAddr.Val == BROADCAST_ADDRESS) )
|
| 564 |
{
|
| 565 |
return s;
|
| 566 |
}
|
| 567 |
}
|
| 568 |
|
| 569 |
partialMatch = s;
|
| 570 |
}
|
| 571 |
p++;
|
| 572 |
}
|
| 573 |
|
| 574 |
if ( partialMatch != INVALID_UDP_SOCKET )
|
| 575 |
{
|
| 576 |
p = &UDPSocketInfo[partialMatch];
|
| 577 |
|
| 578 |
memcpy((void*)&p->remoteNode,
|
| 579 |
(const void*)remoteNode, sizeof(p->remoteNode) );
|
| 580 |
|
| 581 |
p->remotePort = h->SourcePort;
|
| 582 |
}
|
| 583 |
return partialMatch;
|
| 584 |
}
|
| 585 |
|
| 586 |
|
| 587 |
|
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| 
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