addresstranslator.cc

Click is a modular router toolkit. To use it you ll need to know how to compile and install the sof

		    mpi = ipi;
		  }
		else  //inward packet
		  {
		    _v[i]._mai = mai;
		    iai = _v[i]._iai;
		    ipi = mpi;
		  }

		_v[i]._binding = true;
		//_v[i]._t = time(NULL);
		//_v[i]._t = MyEWMA2::now();

		return (true);
	      }

	  }
	}
      return false;
    }


  //dynamic address and port mapping look up
  IP6FlowID fd;
  // create flowid & lookup in the _out_map or _in_map
  if (lookup_direction ==0)  // outward lookup
    {
      fd = IP6FlowID(iai, ipi, ea, ep);
      Mapping *m = _out_map.find(fd);
      if (m) {
	mai = m->flow_id().saddr();
	mpi = m->flow_id().sport();
	return true;
      }
    }
  else //inward lookup
    {
      fd = IP6FlowID(ea, ep, mai, mpi);
      Mapping *m = _in_map.find(fd);
      if (m) {
	iai = m->flow_id().daddr();
	ipi = m->flow_id().dport();
	return true;
      }
    }


  if (lookup_direction != _dynamic_mapping_allocation_direction )
    return false;

  // if lookup is not successful, create a new mapping if the lookup_direction is the same as the addressAllocationDirection
  // first find the freeport and its corresponding map address, create new flowid
   // then add to in_map and out_map

  unsigned short new_mport = 0;
  new_mport = find_mport(); //
  //click_chatter("***********new port is %x", new_mport);

  if (!new_mport) {
      click_chatter("AddressTranslator ran out of ports");
      return false;
  }

  if (lookup_direction == 0)
    {
      mpi = new_mport;
      mai = _maddr;
    }
  else
    {
      ipi = new_mport;
      iai = _maddr;
    }

  IP6FlowID orig_out_flow = IP6FlowID(iai, ipi, ea, ep);
  IP6FlowID orig_in_flow  = IP6FlowID(ea, ep, mai, mpi);
  IP6FlowID new_out_flow = IP6FlowID(mai, mpi, ea, ep);
  IP6FlowID new_in_flow  = IP6FlowID(ea, ep, iai, ipi);
  Mapping *out_mapping = new Mapping;
  out_mapping->initialize(new_out_flow);
  Mapping *in_mapping = new Mapping;
  in_mapping->initialize(new_in_flow);
  if (lookup_direction == 0)
    {
      if (mpi==_mportl) //the first port mapping
	{
	  _rover = out_mapping;
	  _rover->set_next(_rover);
	  _rover2= in_mapping;
	  _rover2->set_next(_rover2);
	}
      else
	{
	  out_mapping->set_next(_rover->get_next());
	  _rover->set_next(out_mapping);
	  _rover = out_mapping;
	  in_mapping->set_next(_rover2->get_next());
	  _rover2->set_next(in_mapping);
	  _rover2 = in_mapping;
	}
    }
  else
    {
      if (ipi == _mportl)
	{
	  _rover = in_mapping;
	  _rover->set_next(_rover);
	  _rover2 = out_mapping;
	  _rover2->set_next(_rover2);
	}
      else
	{
	  in_mapping->set_next(_rover->get_next());
	  _rover->set_next(in_mapping);
	  _rover = in_mapping;
	  out_mapping->set_next(_rover2->get_next());
	  _rover2->set_next(out_mapping);
	  _rover2 = out_mapping;
	}
    }

  _out_map.insert(orig_out_flow, out_mapping);
  _in_map.insert(orig_in_flow, in_mapping);
  _nmappings++;
  _nmappings2++;
  return true;

}


void
AddressTranslator::push(int port, Packet *p)
{
  if (port == 0)
    handle_outward(p);
  else
    handle_inward(p);
}



void
AddressTranslator::handle_outward(Packet *p)
{
  click_ip6 *ip6 = (click_ip6 *)p->data();
  unsigned char *start = (unsigned char *)p->data();
  IP6Address ip6_src = IP6Address(ip6->ip6_src);
  IP6Address ip6_msrc;
  IP6Address ip6_dst = IP6Address(ip6->ip6_dst);
  uint16_t sport;
  uint16_t dport;
  uint16_t mport;

  WritablePacket *q= Packet::make(p->length());
  if (q==0) {
    click_chatter("can not make packet!");
    assert(0);
  }


  // create the new packet
  // replace src IP6, src port, and tcp checksum fields in the packet
  unsigned char *start_new = (unsigned char *)q->data();
  memset(q->data(), '\0', q->length());
  memcpy(start_new, start, p->length());
  click_ip6 *ip6_new = (click_ip6 * )q->data();

  if (ip6_new->ip6_nxt ==0x3a) //the upper layer is an icmp6 packet
    {

      unsigned char * icmp6_start = (unsigned char *)(ip6_new +1);
      if (lookup(ip6_src, dport, ip6_msrc, mport, ip6_dst, sport, 0))
	{

	  ip6_new->ip6_src = ip6_msrc;
	  switch (icmp6_start[0])  {
	  case 1  : ;
	  case 3  : ;
	  case 128: ;
	  case 129: {
	    click_icmp6_echo * icmp6 = (click_icmp6_echo *) (ip6_new+1);
	    icmp6->icmp6_cksum=0;
	    icmp6->icmp6_cksum= htons(in6_fast_cksum(&ip6_new->ip6_src, &ip6_new->ip6_dst, ip6_new->ip6_plen, 0x3a, 0, (unsigned char *)icmp6, ip6_new->ip6_plen));
	  }
	  break;
	  case 2: {
	    click_icmp6_pkttoobig * icmp6 = (click_icmp6_pkttoobig *)(ip6_new +1);
	    icmp6->icmp6_cksum=0;
	    icmp6->icmp6_cksum= htons(in6_fast_cksum(&ip6_new->ip6_src, &ip6_new->ip6_dst, ip6_new->ip6_plen, 0x3a, 0, (unsigned char *)icmp6, ip6_new->ip6_plen));
	  }
	  break;
	  case 4: {
	    click_icmp6_paramprob * icmp6 = (click_icmp6_paramprob *)(ip6_new +1);
	    icmp6->icmp6_cksum=0;
	    icmp6->icmp6_cksum= htons(in6_fast_cksum(&ip6_new->ip6_src, &ip6_new->ip6_dst, ip6_new->ip6_plen, 0x3a, 0, (unsigned char *)icmp6, ip6_new->ip6_plen));
	  }
	  break;
	  default: ; break;
	  }

	  p->kill();
	  output(0).push(q);
	}
      else
	{
	  //click_chatter(" failed for mapping the ip6 address and port for an icmpv6 packet ");
	  p->kill();
	}
    }


  else if (ip6_new->ip6_nxt ==0x6) //the upper layer is a tcp packet
    {
       click_tcp *tcp_new  = (click_tcp *)(ip6_new+1);
       sport = ntohs(tcp_new->th_sport);
       dport = ntohs(tcp_new->th_dport);

      if (lookup(ip6_src, sport, ip6_msrc, mport, ip6_dst, dport, 0))
	{
	  ip6_new->ip6_src = ip6_msrc;
	  tcp_new->th_sport = htons(mport);
	  //recalculate the checksum for TCP, deal with fragment later
	  tcp_new->th_sum = 0;
	  tcp_new->th_sum = htons(in6_fast_cksum(&ip6_new->ip6_src, &ip6_new->ip6_dst, ip6_new->ip6_plen, ip6_new->ip6_nxt, tcp_new->th_sum, (unsigned char *)tcp_new, ip6_new->ip6_plen));
	  p->kill();
	  output(0).push(q);
	}
      else
	{
	  //click_chatter(" failed to map the ip6 address and port for a tcp packet");
	  p->kill();
	}
    }

  else if (ip6_new->ip6_nxt ==0x11) //the upper layer is a udp packet
    {
      click_udp *udp_new  = (click_udp *)(ip6_new+1);
      sport = ntohs(udp_new->uh_sport);
      dport = ntohs(udp_new->uh_dport);

      if (lookup(ip6_src, sport, ip6_msrc, mport, ip6_dst, dport, 0))
	{
	  ip6_new->ip6_src = ip6_msrc;
	  udp_new->uh_sport = htons(mport);
	  //recalculate the checksum for UDP, deal with fragment later
	  udp_new->uh_sum = 0;
	  udp_new->uh_sum = htons(in6_fast_cksum(&ip6_new->ip6_src, &ip6_new->ip6_dst, ip6_new->ip6_plen, ip6_new->ip6_nxt, udp_new->uh_sum, (unsigned char *)udp_new, ip6_new->ip6_plen));
	  p->kill();
	  output(0).push(q);
	}
      else
	{
	  //click_chatter(" failed to map the ip6 address and port for a udp packet");
	  p->kill();
	}
    }

  else //discard other packets
    {
      click_chatter(" discard the packet, protocol unrecognized");
      p->kill();
    }

}

void
AddressTranslator::handle_inward(Packet *p)
{
click_ip6 *ip6 = (click_ip6 *)p->data();
  unsigned char *start = (unsigned char *)p->data();
  IP6Address ip6_src = IP6Address(ip6->ip6_src);
  IP6Address ip6_mdst = IP6Address(ip6->ip6_dst);
  IP6Address ip6_dst ;
  uint16_t sport;
  uint16_t mport;
  uint16_t dport;


  WritablePacket *q= Packet::make(p->length());
  if (q==0) {
    click_chatter("can not make packet!");
    assert(0);
  }


  // create the new packet
  // replace src ip6, src port, and tcp checksum  fields in the packet
  unsigned char *start_new = (unsigned char *)q->data();
  memset(q->data(), '\0', q->length());
  memcpy(start_new, start, p->length());
  click_ip6 *ip6_new = (click_ip6 * )q->data();

  if (ip6_new->ip6_nxt ==0x3a) //the upper layer is an icmp6 packet

     {
      unsigned char * icmp6_start = (unsigned char *)(ip6_new +1);
      //unsigned char *ip6_new2 = 0;

      if (lookup(ip6_dst, dport, ip6_mdst, mport, ip6_src, sport, 1))
	{
	   ip6_new->ip6_dst = ip6_dst;
	   switch (icmp6_start[0])  {
	   case 1  : ;  //need to change
	   case 3  : ;  //need to change
	   case 128: ;
	   case 129: {
	     click_icmp6_echo * icmp6 = (click_icmp6_echo *)(ip6_new +1);
	     icmp6->icmp6_cksum = 0;
	     icmp6->icmp6_cksum = htons(in6_fast_cksum(&ip6_new->ip6_src, &ip6_new->ip6_dst, ip6_new->ip6_plen, 0x3a, 0, (unsigned char *)icmp6, ip6_new->ip6_plen));
	   }
	   break;
	   case 2: {
	     click_icmp6_pkttoobig * icmp6 = (click_icmp6_pkttoobig *)(ip6_new +1);
	     icmp6->icmp6_cksum = 0;
	     icmp6->icmp6_cksum = htons(in6_fast_cksum(&ip6_new->ip6_src, &ip6_new->ip6_dst, ip6_new->ip6_plen, 0x3a, 0, (unsigned char *)icmp6, ip6_new->ip6_plen));
	   }
	   break;
	   case 4: {
	     click_icmp6_paramprob * icmp6 = (click_icmp6_paramprob *)(ip6_new +1);
	     icmp6->icmp6_cksum = 0;
	     icmp6->icmp6_cksum = htons(in6_fast_cksum(&ip6_new->ip6_src, &ip6_new->ip6_dst, ip6_new->ip6_plen, 0x3a, 0, (unsigned char *)icmp6, ip6_new->ip6_plen));
	   }
	   break;
	   default: ;
	   }

	  p->kill();
	  output(1).push(q);
	}
      else
	{
	  //click_chatter(" failed for mapping the dst ip6 address and port for an icmpv6 packet -inward");
	  p->kill();
	}
    }


  else if (ip6_new->ip6_nxt ==0x6) //the upper layer is a tcp packet
    {
       click_tcp *tcp_new  = (click_tcp *)(ip6_new+1);
       sport = ntohs(tcp_new->th_sport);
       mport = ntohs(tcp_new->th_dport);
      if (lookup(ip6_dst, dport,ip6_mdst, mport, ip6_src, sport, 1))
	{
	  ip6_new->ip6_dst = ip6_dst;
	  tcp_new->th_dport = htons(dport);
	  //recalculate the checksum for TCP, deal with fragment later
	  tcp_new->th_sum = 0;
	  tcp_new->th_sum = htons(in6_fast_cksum(&ip6_new->ip6_src, &ip6_new->ip6_dst, ip6_new->ip6_plen, ip6_new->ip6_nxt, tcp_new->th_sum, (unsigned char *)tcp_new, ip6_new->ip6_plen));


	  p->kill();
	  output(1).push(q);
	}
       else
	{
	  //click_chatter(" failed for mapping the dst ip6 address and port for a tcp packet -inward");
	  p->kill();
	}
    }


  else if (ip6_new->ip6_nxt ==0x11) //the upper layer is a udp packet
    {
       click_udp *udp_new  = (click_udp *)(ip6_new+1);
       sport = ntohs(udp_new->uh_sport);
       mport = ntohs(udp_new->uh_dport);
      if (lookup(ip6_dst, dport,ip6_mdst, mport, ip6_src, sport, 1))
	{
	  ip6_new->ip6_dst = ip6_dst;
	  udp_new->uh_dport = htons(dport);
	  //recalculate the checksum for TCP, deal with fragment later
	  udp_new->uh_sum = 0;
	  udp_new->uh_sum = htons(in6_fast_cksum(&ip6_new->ip6_src, &ip6_new->ip6_dst, ip6_new->ip6_plen, ip6_new->ip6_nxt, udp_new->uh_sum, (unsigned char *)udp_new, ip6_new->ip6_plen));

	  p->kill();
	  output(1).push(q);
	}
       else
	{
	  //click_chatter(" failed for mapping the dst ip6 address and port for a udp packet - inward");
	  p->kill();
	}
    }

  else //discard other packets
    {
      click_chatter(" discard the packet, protocol unrecognized");
      p->kill();
    }
}

EXPORT_ELEMENT(AddressTranslator)
CLICK_ENDDECLS