Diff: eth/eth.cpp

Revision:

59:e0e556c8bd46

Parent:

57:e0fb648acf48

--- a/eth/eth.cpp	Thu Dec 07 20:44:32 2017 +0000
+++ b/eth/eth.cpp	Thu Dec 14 20:55:40 2017 +0000
@@ -6,11 +6,11 @@
 #include    "arp.h"
 #include    "ip4.h"
 #include    "ip6.h"
-#include    "phy.h"
+#include   "link.h"
 #include    "eth.h"
 #include    "mac.h"
 
-#define HEADER_SIZE 14
+#define MTU 1500
 
 //header variables
 __packed struct header
@@ -30,20 +30,6 @@
         default:   LogF("%04hX", prototype); break;
     }
 }
-
-static void finalisePacket(int dest, int dataLength, void* pPacket, int* pSize)
-{
-    if (!dest) return;
-    
-    struct header * pHeader = (header*)pPacket;
-        
-    MacMakeFromDest(dest, protocol, pHeader->dst);
-
-    MacCopy(pHeader->src, MacLocal);        //Put our MAC into the source
-    pHeader->typ = NetToHost16(protocol);
-    
-    *pSize = HEADER_SIZE + dataLength;
-}
 void LogHeader(struct header* pHeader)
 {
     if (NetTraceVerbose)
@@ -64,35 +50,38 @@
         Log("\r\n");
     }
 }
-static void (*pTraceBack)(void);
 static void* tracePacket;
 static void trace()
 {
-    pTraceBack();
     struct header * pHeader = (header*)tracePacket;
     LogHeader(pHeader);
 }
-int EthHandlePacket(void (*traceback)(void), void* pPacket, int* pSize)
+int EthHandlePacket(void* pPacketRx, int sizeRx, void* pPacketTx, int* pSizeTx)
 {
-    pTraceBack = traceback;
-    tracePacket = pPacket;
-    struct header * pHeader = (header*)pPacket;
-    int dataLength = *pSize - HEADER_SIZE;
-    void* pData = (char*)pPacket + HEADER_SIZE;
+    tracePacket = pPacketRx;
+    
+    struct header * pHeaderRx = (header*)pPacketRx;
+    struct header * pHeaderTx = (header*)pPacketTx;
+    void* pDataRx = (char*)pPacketRx + sizeof(header);
+    void* pDataTx = (char*)pPacketTx + sizeof(header);
+    int dataLengthRx =   sizeRx - sizeof(header);
+    int dataLengthTx = *pSizeTx - sizeof(header);
+    if (dataLengthTx > MTU) dataLengthTx = MTU; //Limit the transmitted length to the maximum ethernet frame payload length
         
-    if (!MacAccept(pHeader->dst)) return DO_NOTHING;
+    if (!MacAccept(pHeaderRx->dst)) return DO_NOTHING;
     
-    protocol = NetToHost16(pHeader->typ);
+    protocol = NetToHost16(pHeaderRx->typ);
     if (protocol < 1500) return DO_NOTHING; //drop 802.3 messages
 
-    NetTraceHostCheckMac(pHeader->src);
+    NetTraceHostCheckMac(pHeaderRx->src);
 
     int   action = DO_NOTHING;
+    char* macRemote = pHeaderRx->src;
     switch (protocol)
     {
-        case ARP:  action = ArpHandleReceivedPacket(trace, pHeader->src, pData, &dataLength, pHeader->dst); break;
-        case IPV4: action = Ip4HandleReceivedPacket(trace, pHeader->src, pData, &dataLength, pHeader->dst); break;
-        case IPV6: action = Ip6HandleReceivedPacket(trace, pHeader->src, pData, &dataLength, pHeader->dst); break;
+        case ARP:  action = ArpHandleReceivedPacket(trace, pDataRx, dataLengthRx, pDataTx, &dataLengthTx);            break;
+        case IPV4: action = Ip4HandleReceivedPacket(trace, pDataRx, dataLengthRx, pDataTx, &dataLengthTx, macRemote); break;
+        case IPV6: action = Ip6HandleReceivedPacket(trace, pDataRx, dataLengthRx, pDataTx, &dataLengthTx, macRemote); break;
         case 0x6970: break; //Drop Sonos group membership packet
         case 0x7374: break; //Drop Sky Q packet
         case 0x7475: break; //Drop Sky Q packet
@@ -104,22 +93,26 @@
             break;
     }
     if (!action) return DO_NOTHING;
+        
+    MacMakeFromDest(ActionGetDestPart(action), protocol, macRemote);
+    MacCopy(pHeaderTx->src, MacLocal);
+    MacCopy(pHeaderTx->dst, macRemote);
+    pHeaderTx->typ = NetToHost16(protocol);
     
-    finalisePacket(ActionGetDestPart(action), dataLength, pPacket, pSize);
+    *pSizeTx = sizeof(header) + dataLengthTx;
     
-    if (ActionGetTracePart(action)) LogHeader(pHeader);
+    if (ActionGetTracePart(action)) LogHeader(pHeaderTx);
     
     return action;
 }
 int EthPollForPacketToSend(void* pPacket, int* pSize)
 {
     struct header * pHeader = (header*)pPacket;
-    void* pData = (char*)pPacket + HEADER_SIZE;
+    void* pData = (char*)pPacket + sizeof(header);
     
     int dataLength = 0;
     protocol = 0;
     int action = DO_NOTHING;
-
     if (!action)
     {
         action = ArpPollForPacketToSend(pData, &dataLength);
@@ -140,7 +133,11 @@
     
     if (!action) return DO_NOTHING;
     
-    finalisePacket(ActionGetDestPart(action), dataLength, pPacket, pSize);
+    MacMakeFromDest(ActionGetDestPart(action), protocol, pHeader->dst);
+    MacCopy(pHeader->src, MacLocal);
+    pHeader->typ = NetToHost16(protocol);
+    
+    *pSize = sizeof(header) + dataLength;
     
     if (ActionGetTracePart(action)) LogHeader(pHeader);