#include <stdio.h>
#include <netdb.h>
#include <stdlib.h>
#include <strings.h>

#include "main.h"
#include "route.h"
#include "l2tp.h"
#include "rpc.h"
#include "udp.h"
#include "util.h"
#include "vars.h"

unsigned short int uh_sport;
unsigned short int uh_dport;

static const char *udp_ports[65536];

static const char *portcache(int port)
{
 if (! udp_ports[port])
  { struct servent *sp;
    sp = getservbyport(port,"udp");
    if (sp)
     { char *tmp;
       tmp = malloc(1+strlen(sp->s_name)+1);
       sprintf(tmp,"=%s",sp->s_name);
       udp_ports[port] = tmp;
     }
    else
     { udp_ports[port] = "";
     }
  }
 return(udp_ports[port]);
}

void dump_udp(void)
{
 unsigned long int uh_ulen;
 unsigned short int uh_sum;

 need(8,"UDP header");
 printx(pkt,2);
 uh_sport = get16(0);
 printf("uh_sport [%d%s]\n",uh_sport,portcache(uh_sport));
 consume(2);
 printx(pkt,2);
 uh_dport = get16(0);
 printf("uh_dport [%d%s]\n",uh_dport,portcache(uh_dport));
 consume(2);
 printx(pkt,2);
 uh_ulen = get16(0);
 printf("uh_ulen [%lu]",uh_ulen);
 if (uh_ulen < pktleft+4)
  { printf(" (dropping %lu trailing byte%s)",pktleft+4-uh_ulen,((pktleft+4-uh_ulen)==1)?"":"s");
    pktleft = uh_ulen - 4;
  }
 printf("\n");
 if (uh_ulen < 8)
  { printf("*** Claimed header size too small\n");
    dumpabort();
  }
 if (uh_ulen > pktleft+4)
  { printf("*** UDP header claims %lu bytes in packet but have only %d\n",uh_ulen,pktleft+4);
    dumpabort();
  }
 /* maybe do something if uh_ulen > pktleft+4? */
 consume(2);
 printx(pkt,2);
 uh_sum = get16(0);
 printf("uh_sum\n");
 consume(2);
 if ((uh_dport == 520) || (uh_sport == 520))
  { dump_route();
  }
 else if ((uh_sport == 1701) && (uh_dport == 1701))
  { dump_l2tp();
  }
 else
  { maybe_dump_rpc();
  }
}