input from barcode

if i understand you your asking for a list of coodcard bar code's

I was asking if you had created an array of such values in your code. If not, you can modify goodCards and use those values:
char *goodCards = { "3455192327218", "4005209057240", "5060048310337" };

After this:

	if(dataValue == SCAN_ENTER){
		Serial.print("\nbuffer: ");

Put this:

int goodMatch = -1;

for(int c=0; c<cardCnt; c++)
{
   if(strcmp(buffer, goodCards[c]) == 0)
   {
      goodMatch = c;
      break;
   }
}

Serial.print("goodMatch  = ");
Serial.println(goodMatch);     // Will print index of good card in array