AntiGuide: ArduinoEthernetBridgeIpFixeHubNonSwitch

// Simple demo tcpdump http://anntguide.free.fr

#include <EtherCard.h>
#define Ethernet ENC28J60 

// ethernet interface mac address, must be unique on the LAN
byte mymac[] = { 0,1,2,3,4,5 };
//byte PEERIP[4]={81,57,148,97};
byte PEERIP[4]={192,168,0,235};
//byte MACCLIENT[6]={3,4,5,6,7,8};
byte MACCLIENT[6]={0,36,33,7,142,37};  // acer m1641
byte tampon[2000];
#define PORT 1000
#define LAGMACFROM 6
#define LAGIPFROM 30
#define MAXLOAD 1300 
//#define LONPREMS 1300
#define LONTETEUDP 40 // ntete UDP
#define PINCS 10

byte ENC28J60::buffer[500];
uint32_t timer;
static int biglen;
int ICMP=1;
int TCP=0;
int okmac=0 ; // passe a true si recu un paquet du client
int okpeer=0; // passe a 1 si pauet (udp, recu de peer)
int okreste=0 ; // paquet bifide
int numin=0;
int numout=0;
void setup () {
  Serial.begin(9600);
  Serial.println("[Gadget]");
  digitalWrite(10,HIGH);
    Serial.print( "Aaccess Ethernet controller...");
  if (ether.begin(sizeof Ethernet::buffer, mymac,53) == 0) {
    Serial.println( "Failed!");
    return;
  }
    Serial.println( "Succes.!");
  if (!ether.dhcpSetup())
    Serial.println("DHCP failed");

  ether.printIp("IP:  ", ether.myip);
  ether.printIp("GW:  ", ether.gwip);  
  ether.printIp("DNS: ", ether.dnsip);  
    
 
 // prtdump("andiamo",10);
 testsendudp();
}

void testsendudp (){
  tampon[0]=44;
  
     ether.sendUdp((char*)tampon,1,PORT,PEERIP,PORT);

}
void prhexa(int base,int nb, char *t){
  for (int iii=0;iii<nb;iii=iii+1) {
      Serial.print((byte) ether.buffer[base+iii]);
      Serial.print(" ");
  }
  Serial.print("<-- ");
  Serial.println(t);
}

void dump (int deb, int fin){
  Serial.print("dump buffer a partir de " );
  Serial.print(deb);
  Serial.print(" à ");
  Serial.println(fin);
  for (int iii=deb;iii<fin;iii=iii+1) Serial.print ((char)ether.buffer[iii]);
  Serial.println("");
   Serial.println("------------------");
  for (int iii=deb;iii<fin;iii=iii+1) { 
       Serial.print (ether.buffer[iii]);
       Serial.print(" ");
  }
   Serial.println("------------------");
}
void prtdump(char *tt,int tout){
Serial.println("------------------");
Serial.println(tt);
Serial.println("------------------");
  prhexa(0,6,"to mac ");
  prhexa(6,6,"from mac ");
  prhexa(12,2,"ehr type (8) ");
  prhexa(14,1," version ");
  prhexa(15,1," service ");
  prhexa(16,2," big len ");
 biglen=ether.buffer[16]*256+ether.buffer[17];
 Serial.print("           ");  Serial.print(biglen);Serial.println(" decimal ");
  prhexa(18,2," id ");
  prhexa(20,2," flag ");
  prhexa(22,1," ttl ");
  prhexa(23,1," next ");
  if (ether.buffer[23]==1){ ICMP=1;Serial.println("ICMP");}
  if (ether.buffer[23]==6) {TCP=1;Serial.println("TCP");}
  prhexa(24,2," chk ");
  prhexa(26,4," source ip ");
  prhexa(30,4," dest ip ");
  if (ICMP) {
  prhexa(34,1," type 8 ");
  prhexa(35,1," code 0 ");
  prhexa(36,2," chk ");
  prhexa(38,2," id 4019 ");
  prhexa(40,2," seq num ");
  dump (42,biglen);
  }
  if (TCP) {
  prhexa(34,2," source port ");
  prhexa(36,2," dest port ");
  prhexa(38,4," seq num ");
  prhexa(42,4," ack num ");
  prhexa(46,2," hdr len ");
  prhexa(48,2," reserved ");
  dump (50,biglen);
  }
  
  Serial.println("");
Serial.println("------------------");
}

void loop () {
  if (okmac>0) {
  Serial.println("envoyer a peer en 1 ou deux bouts du paquet reçu du clientt");
   // evoyer tout le début
    // void EtherCard::sendUdp (char *data,byte datalen,word sport, byte *dip, word dport) {
      int londeb=okmac;
      int lonsup=-1;
      if (okmac<=MAXLOAD) { 
     }else{
       londeb=MAXLOAD;
       lonsup=okmac-MAXLOAD ; // may be 0!
     }
     
     ether.sendUdp((char*)tampon,londeb,PORT,PEERIP,PORT);
    if (lonsup>=0)  ether.sendUdp((char*)tampon+MAXLOAD,lonsup,PORT,PEERIP,PORT);
     okmac=0;
//    is il en reste   okreste=1;
    return;
  }
  
 if (okreste) {
  Serial.println("envoyer a peer le este (eventuellement vide) du  paquet client");
    // evoyer le reste
     okreste=0;
//    is il en reste   okreste=1;
    return;
  }
  
word q=  ether.packetReceive();

 if (q>64) {  prtdump("recu",q);}

if (q>0) {
Serial.print("recu paquet de lon=");Serial.println(q);
// tester from mac
okmac=1;
 for (int imac=0;imac<6;imac=imac+1) if (ether.buffer[LAGMACFROM+imac]!=MACCLIENT[imac])  {
    Serial.print("different a ");Serial.print(ether.buffer[LAGMACFROM+imac]);
    Serial.print("<>"); Serial.print(MACCLIENT[imac]);Serial.print(" at ");Serial.println(imac) ;
    okmac=0;
 }
if (okmac) { // mettre de côté lepaqut 
 Serial.println("recu paquet de client");

 for (int imac=0;imac<q;imac=imac+1) tampon[imac]=ether.buffer[imac];
 okmac=q;
  return;
}else Serial.println("pas du client");

// tester si paquet vient de peer ?
okpeer=1;
for (int iip=0;iip<4;iip=iip+1)    if (ether.buffer[LAGIPFROM+iip]!=PEERIP[iip]) okpeer=0; 

if (okpeer) {
 numin=numin+1;
 Serial.print (numin);
 Serial.print(" recu paquet de peer lon= ");
 Serial.println(q);
// gaffe si plusieurs
 if (q==MAXLOAD) {
   // conserver 
   for (int iprem=0;iprem<q;iprem=iprem+1) tampon[iprem]=ether.buffer[LONTETEUDP+iprem];
 Serial.println("memorise paquet ==  mMAXLOAD ");
   
   return;
 }
   // copier au bout
 // envoyer tout
Serial.println("envoyer contenu du paquet  ");
      ether.sendEthernet((char*)tampon+LONTETEUDP,okmac-LONTETEUDP,PORT);
}
  
}
word resu=  ether.packetLoop(q);
if (resu>0){ Serial.print(resu);
 Serial.println("");}
 }