Diff: tcp/tcp.c

Revision:

74:c3756bfa960e

Parent:

73:43e3d7fb3d60

Child:

88:1ba13e6062a3

--- a/tcp/tcp.c	Tue Oct 23 06:46:50 2018 +0000
+++ b/tcp/tcp.c	Mon Oct 29 09:33:44 2018 +0000
@@ -1,260 +1,5 @@
-#include <stdint.h>
 #include <stdbool.h>
 
-#include    "log.h"
-#include    "net.h"
-#include "action.h"
-#include    "tcp.h"
-#include "tcphdr.h"
-#include    "tcb.h"
-#include    "ip4.h"
-#include   "dhcp.h"
-#include   "http.h"
-#include    "led.h"
-
-
-//Payload variables
-static int dataLength;
-static int maxMss = 0;
-
 bool TcpTrace = false;
-static bool doTrace = false;
-
-static struct tcb* pTcb;
-
-static void resetConnectionOut(char* message)
-{
-    if (TcpTrace)
-    {
-        LogTime("TCP ");
-        Log(message);
-        Log("\r\n");
-    }
-    dataLength = 0;
-    TcpHdrClearOptions();
-    TcpHdrACK = false;
-    TcpHdrPSH = false;
-    TcpHdrRST = true;
-    TcpHdrSYN = false;
-    TcpHdrFIN = false;
-    
-    pTcb->state = TCB_EMPTY;
-}
-static void startConnectionIn(void *pPacket, void* pCachedRemIp)
-{
-    TcpHdrReadOptions(pPacket);                 //Get the MSS
-    if (TcpHdrMss > maxMss) TcpHdrMss = maxMss;
-    
-    pTcb->mss     = TcpHdrMss;
-    pTcb->state   = TCB_SYN_RECEIVED;
-    pTcb->elapsed = TcbElapsed;
-    pTcb->pIp     = pCachedRemIp;
-    pTcb->port    = TcpHdrSrcPort;
-    pTcb->hadFin  = false;
-}
-static void startConnectionOut(void* pPacket)
-{
-    TcpHdrMss = maxMss;                 //Ethernet 1500 - 20 - 20; or, in our case 768 - 20 - 20
-    TcpHdrWriteOptions(pPacket);
-    dataLength = 0;
-   
-    TcpHdrACK = true;                    //Send ACK and SYN
-    TcpHdrPSH = false;
-    TcpHdrRST = false;
-    TcpHdrSYN = true;
-    TcpHdrFIN = false;
-}
-static void establishConnectionIn()
-{
-    pTcb->state   = TCB_ESTABLISHED;
-    pTcb->elapsed = TcbElapsed;
-    pTcb->todo    = 0;
-}
-static void handleEstablishedConnectionIn(void* pPacket)
-{
-    char* pData = (char*)pPacket + TcpHdrSize;
-    HttpHandleRequest(dataLength, pData, pTcb->recdBytes - 1, &pTcb->todo);
-}
-static void handleEstablishedConnectionOut(void* pPacket)
-{
-    TcpHdrClearOptions();
-    char* pData = (char*)pPacket + TcpHdrSize;
-    HttpSendReply(&dataLength, pData, pTcb->sentBytes - 1, TcpHdrMss, pTcb->todo);
-    
-    TcpHdrACK = true;                 //Send ACK
-    TcpHdrRST = false;
-    TcpHdrSYN = false;
-    TcpHdrPSH = false;
-    
-    if (dataLength < TcpHdrMss) //If a part packet then there can be no more to send
-    {
-        TcpHdrFIN = true;       //Inform the client that we have no more to send after this
-        if (pTcb->hadFin) pTcb->state = TCB_ACK_WAIT; //Passive close
-        else              pTcb->state = TCB_FIN_WAIT; //Active close
-    }
-    else
-    {
-        TcpHdrFIN = false;
-    }
-
-    pTcb->elapsed = TcbElapsed;
-}
-static void closeConnectionOut()
-{        
-    TcpHdrACK = true;               //Send ACK
-    TcpHdrPSH = false;
-    TcpHdrRST = false;
-    TcpHdrSYN = false;
-    TcpHdrFIN = false;
-    
-    TcpHdrClearOptions();
-    dataLength = 0;
-    
-    pTcb->state  = TCB_EMPTY;
-}
+bool TcpDoTrace = false;
 
-int TcpHandleReceivedPacket(void (*traceback)(void), int sizeRx, void* pPacketRx, int* pSizeTx, void* pPacketTx, int type, void* pCachedRemIp)
-{
-    TcpHdrRead(pPacketRx);
-    
-    dataLength =   sizeRx - TcpHdrSize;
-    maxMss     = *pSizeTx - TcpHdrSize;
-        
-    doTrace = false;
-    
-    //Filter out unwanted links
-    switch (TcpHdrDstPort)
-    {
-        case 80:
-            if (HttpTrace)
-            {
-                if (NetTraceNewLine) Log("\r\n");
-                LogTime("HTTP server request\r\n");
-                doTrace = true;
-            }
-            break;
-            
-        default:
-            if (TcpTrace)
-            {
-                if (NetTraceNewLine) Log("\r\n");
-                LogTimeF("TCP unknown port %d\r\n", TcpHdrDstPort);
-                if (NetTraceStack) traceback();
-            }
-            return DO_NOTHING; //Ignore unknown ports
-    }
-    
-    //Get the Transmission Control Block
-    pTcb = TcbGetExisting(TcpHdrSrcPort);
-    if (!pTcb)  pTcb = TcbGetEmpty();
-    if (!pTcb)
-    {
-        if (TcpTrace)
-        {
-            if (NetTraceNewLine) Log("\r\n");
-            LogTime("TCP no more tcbs are available\r\n");
-            if (NetTraceStack) traceback();
-        }
-        return DO_NOTHING; //Bomb out if no more tcbs are available
-    }
-
-    //Handle request to reset
-    if (TcpHdrRST)
-    {
-        if (TcpTrace)
-        {
-            if (NetTraceNewLine) Log("\r\n");
-            LogTime("TCP received reset - resetting TCB\r\n");
-            if (NetTraceStack) traceback();
-        }
-        pTcb->state  = TCB_EMPTY; //Reset connection
-        return DO_NOTHING;        //Don't reply
-    }
-    
-    //Handle request to synchronise
-    if (TcpHdrSYN)
-    {
-        pTcb->recvIsn   = TcpHdrSeqNum;
-        pTcb->sendIsn   = TcbGetIsn();
-        pTcb->recdBytes = 0;
-        pTcb->sentBytes = 0;
-    }
-    else
-    {
-        pTcb->recdBytes = TcpHdrSeqNum - pTcb->recvIsn;
-        pTcb->sentBytes = TcpHdrAckNum - pTcb->sendIsn;
-    }
-        
-    if (doTrace && NetTraceStack) traceback(); //This will already include the TCP header
-    
-    if (TcpHdrSYN) pTcb->recdBytes += 1;            //Add one to acknowledge the SYN
-                   pTcb->recdBytes += dataLength;   //Add the number of bytes received
-    if (TcpHdrFIN) pTcb->recdBytes += 1;            //Add one to acknowledge the FIN
-
-    switch (pTcb->state)
-    {
-        case TCB_EMPTY:
-            if (!TcpHdrSYN) { resetConnectionOut("received other than a SYN when connection closed"); break; }
-            startConnectionIn(pPacketRx, pCachedRemIp);
-            startConnectionOut(pPacketTx);
-            break;
-            
-        case TCB_SYN_RECEIVED:
-            if (dataLength) { resetConnectionOut("data received before connection established"); break; }
-            if (!TcpHdrACK)       { resetConnectionOut("received other than an ACK before connection established"); break; }
-            establishConnectionIn();
-            return DO_NOTHING;
-            
-        case TCB_ESTABLISHED:
-            if (!TcpHdrACK) { resetConnectionOut("received other than an ACK during established conection"); break; }
-            if (TcpHdrFIN) pTcb->hadFin = true; //When reply is all sent only a passive close is needed
-            handleEstablishedConnectionIn (pPacketRx);
-            handleEstablishedConnectionOut(pPacketTx);
-            break;
-            
-        case TCB_FIN_WAIT: //End of active close
-            if (!TcpHdrFIN) return DO_NOTHING; //Ignore ACK to our FIN. Wait for FIN then close.
-            closeConnectionOut();
-            break;
-            
-        case TCB_ACK_WAIT: //End of passive close
-            if (!TcpHdrACK) { resetConnectionOut("received other than an ACK when closing half open connection"); break; } 
-            pTcb->state = TCB_EMPTY;
-            return DO_NOTHING;
-    }
-    
-    //Specify the start of the data being sent and acknowledge the data received
-    TcpHdrAckNum = pTcb->recdBytes + pTcb->recvIsn;       //Set up the acknowledgement field ready to send
-    TcpHdrSeqNum = pTcb->sentBytes + pTcb->sendIsn;       //Set up the start of the message before adding the bytes sent
-    
-    //Keep a record of where we expect the next packet send to start
-    if (TcpHdrSYN) pTcb->sentBytes += 1;           //Add one to acknowledge the SYN
-                   pTcb->sentBytes += dataLength;  //Record the next sequence number
-    if (TcpHdrFIN) pTcb->sentBytes += 1;           //Add one to acknowledge the FIN
-    
-    //Swap the ports for the reply
-    TcpHdrSrcPort = TcpHdrDstPort;
-    TcpHdrDstPort = pTcb->port;
-    
-    //Specify the receive window size to not throttle
-    TcpHdrWindow = 4000;
-    
-    //Calculate the size of the reply
-    *pSizeTx = TcpHdrSize + dataLength;
-        
-    return ActionMakeFromDestAndTrace(UNICAST, doTrace && NetTraceStack);
-}
-
-int TcpPollForPacketToSend(int* pSize, void* pPacket, int type, void* pCachedRemIp)
-{    
-    int dataLength =         *pSize - TcpHdrSize;
-    
-    int action = DO_NOTHING;
-    
-    TcpHdrSrcPort = TcpHdrDstPort;
-    TcpHdrDstPort = pTcb->port;
-    
-    *pSize =  TcpHdrSize + dataLength;
-    return action;
-}
-