sicslow_ethernet.c

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/**
 * \file sicslow_ethernet.c
 *         Routines to interface between Ethernet and 6LowPan
 *
 * \author
 *         Colin O'Flynn <coflynn@newae.com>
 *
 * \addtogroup usbstick 
 */

/* Copyright (c) 2008 by:
 * Colin O'Flynn coflynn@newae.com
 * Eric Gnoske egnoske@gmail.com
 * Blake Leverett bleverett@gmail.com
 * Mike Vidales mavida404@gmail.com
 * Kevin Brown kbrown3@uccs.edu
 * Nate Bohlmann nate@elfwerks.com
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 * * Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in
 * the documentation and/or other materials provided with the
 * distribution.
 * * Neither the name of the copyright holders nor the names of
 * contributors may be used to endorse or promote products derived
 * from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

/**
   \ingroup usbstick
   \defgroup sicslowinterop 6LowPan Ethernet Interop
   @{
*/

//TODO: Should be able to always use this SIMPLE mode, hence can remove the 'complex' mode permanently
//TODO: RF230BB !SIMPLE works on XP, Ubuntu. SIMPLE works on Vista, W7. Find out why!

#ifndef UIP_CONF_SIMPLE_JACKDAW_ADDR_TRANS
#define UIP_CONF_SIMPLE_JACKDAW_ADDR_TRANS 0
#endif // ifndef UIP_CONF_SIMPLE_JACKDAW_ADDR_TRANS

#ifndef UIP_CONF_AUTO_SUBSTITUTE_LOCAL_MAC_ADDR
#define UIP_CONF_AUTO_SUBSTITUTE_LOCAL_MAC_ADDR 1
#endif // ifndef UIP_CONF_AUTO_SUBSTITUTE_LOCAL_MAC_ADDR

#if UIP_CONF_SIMPLE_JACKDAW_ADDR_TRANS
/**
   \par Ethernet to 6LowPan Address Translation

   It should be obvious that since 802.15.4 addresses are 8
   bytes, and 802.3 addresses are 6 bytes, some form of
   address translation is needed. These routines provide this

   \par Address Translation on Packets coming FROM Ethernet

   Packets coming from Ethernet, have any addresses inside
   IPv6 packets (such as 'source link-layer address') expanded
   by inserting a 0xFF 0xFE sequence as such:

   \verbatim
   AA:BB:CC:DD:EE:FF

   becomes

   AA:BB:CC:FF:FE:DD:EE:FF
   \endverbatim

   The 802.15.4 destination address is always derived from the IPv6
   destination address.

   \par Address Translation on Packets coming FROM 802.15.4

   Packets coming from 802.15.4, have any addresses inside IPv6
   packets (such as a 'source link-layer address') replaced
   with the local_ethernet_addr, defined to 3A:3B:3C:3D:3E:3F here.

   The destination ethernet address is performed by performing
   the reverse process used to make the 802.15.4 addresses before.

   \par Comments on Using This

   Thus you always send IPv6 messages to the local_ethernet_addr,
   which is 3A:3B:3C:3D:3E:3F. The actual 802.15.4 destination
   address is based on the lower 64-bits of your IPv6 destination
   address. IPv6 addresses must always be based on link-layer
   addresses in the 802.15.4 network for this to work.

   \par Notes on how addresses are stored

   An 802.15.4 address will be reported for example as:

   0x8877665544332211

   Stored in the array as passed to these functions, it will be:
   \verbatim
   array[0] = 0x88;
   array[1] = 0x77;
   array[2] = 0x66;
   etc.
   \endverbatim

   An 802.3 address will be reported for example as:
   02:43:53:35:45:45

   Stored in the array as passed to these functions, it will be:
   \verbatim
   array[0] = 0x02;
   array[1] = 0x43;
   array[2] = 0x53;
   array[3] = 0x35
   etc.
   \endverbatim
*/
#else
/**
   \par Ethernet to 6LowPan Address Translation
   
   It should be obvious that since 802.15.4 addresses are 8 
   bytes, and 802.3 addresses are 6 bytes, some form of 
   address translation is needed. These routines provide this

   \par 802.3 Address Formats

   802.3 MAC addresses used here have this form:
   
   \verbatim
   +----+----+----+----+----+----+----+----+
   +    +    +    +    +    + TR + GL + MU +
   +----+----+----+----+----+----+----+----+
   \endverbatim


   It can be seen this is like a normal ethernet MAC address, 
   with GL being the Global/Local bit, and MU being the
   Multicast/Unicast bit.

   The addition is the 'TR' bit, which if set indicates that
   the address must be translated when going between 802.15.4
   and 802.3. 

   \par Address Translation

   If the TRANSLATE (TR) bit is CLEAR, this means the 5th and
   4th LSBytes of the 802.15.4 address are fffe, aka the address
   has the hexidecial form:
   
   xxxxxxfffexxxxxx

   \note
   You should always aim to set the 802.15.4 addresses
   of the devices on your network to ones that will
   satisfy this requirement. Some examples are:
   \note
   0x02 23 42 ff fe 73 92 28
   \note
   0x82 00 82 ff fe cd ee 22

   \note
   So the most significant octets MUST
   have bit 0 CLEAR, bit 1 SET, and bit 2 CLEAR. The remaining
   bits in this octet can be anything.

   If the TRANSLATE bit is SET, this means the address on the 
   802.3 side does not directly convert to an 802.15.4 address.
   To translate it, the remainder of the octet is used as an
   index in a look-up table. This look-up table simply stores
   the 4th, 5th, and 8th octet of the 802.15.4 address, and attaches
   them to the remaining 5 bytes of the 802.3 address.

   In this way there can be 32 different 802.15.4 'prefixes', 
   requiring only 96 bytes of RAM in a storage table on the
   802.3 to 802.15.4 bridge. 
  
   Mulitcast addresses on 802.3 are mapped to broadcast addresses on
   802.15.4 and vis-versa. Since IPv6 does not use 802.3 broadcast, 
   this code will drop all 802.3 broadcast packets. They are most
   likely something unwanted, such as IPv4 packets that snuck in.

   \par Notes on how addresses are stored

   An 802.15.4 address will be reported for example as:

   0x8877665544332211

   Stored in the array as passed to these functions, it will be:
   \verbatim
   array[0] = 0x88;
   array[1] = 0x77;
   array[2] = 0x66;
   etc.
   \endverbatim

   An 802.3 address will be reported for example as:
   02:43:53:35:45:45

   Stored in the array as passed to these functions, it will be:
   \verbatim
   array[0] = 0x02;
   array[1] = 0x43;
   array[2] = 0x53;
   array[3] = 0x35
   etc.
   \endverbatim
*/
#endif

#include "uip.h"
#include "uip_arp.h" //For ethernet header structure

#include "net/rime.h"
#include "sicslowpan.h"
#include "sicslow_ethernet.h"
#if !RF230BB
#include "zmac.h"
#include "frame.h"
#include "radio.h"
#endif
#include "rndis/rndis_protocol.h"
#include "rndis/rndis_task.h"

#include <stdint.h>
#include <stdio.h>
#include <string.h>

#define DEBUG 0
#if DEBUG
#define PRINTF(FORMAT,args...) printf_P(PSTR(FORMAT),##args)
#else
#define PRINTF(...)
#endif

#define UIP_IP_BUF   ((struct uip_ip_hdr *)&uip_buf[UIP_LLH_LEN])
#define ETHBUF(x) ((struct uip_eth_hdr *)x)

//For little endian, such as our friend mr. AVR
#ifndef LSB
#define LSB(u16)     (((uint8_t  *)&(u16))[0])  //!< Least significant byte of \a u16.
#define MSB(u16)     (((uint8_t  *)&(u16))[1])  //!< Most significant byte of \a u16.
#endif

static const uint64_t simple_trans_ethernet_addr = 0x3E3D3C3B3AF2ULL;

#if UIP_CONF_IPV6_RPL
static uip_ipaddr_t last_sender;
#endif

extern uint64_t usb_ethernet_addr;

extern uint64_t macLongAddr;

#if !RF230BB
extern void (*pinput)(const struct mac_driver *r);
void (*sicslowinput)(const struct mac_driver *r);
parsed_frame_t * parsed_frame;
#endif
usbstick_mode_t usbstick_mode;

uint8_t mac_createSicslowpanLongAddr(uint8_t * ethernet, uip_lladdr_t * lowpan);
uint8_t mac_createEthernetAddr(uint8_t * ethernet, uip_lladdr_t * lowpan);
uint8_t mac_createDefaultEthernetAddr(uint8_t * ethernet);
void mac_ethhijack_nondata(const struct mac_driver *r);
void mac_ethhijack(const struct mac_driver *r);

extern void (*sicslowmac_snifferhook)(const struct mac_driver *r);


//! Location of TRANSLATE (TR) bit in Ethernet address
#define TRANSLATE_BIT_MASK (1<<2) 
//! Location of LOCAL (GL) bit in Ethernet address
#define LOCAL_BIT_MASK     (1<<1)
//! Location of MULTICAST (MU) bit in Ethernet address
#define MULTICAST_BIT_MASK (1<<0)

#define PREFIX_BUFFER_SIZE 32

uint8_t prefixCounter;
uint8_t prefixBuffer[PREFIX_BUFFER_SIZE][3];

/* 6lowpan max size + ethernet header size + 1 */
uint8_t raw_buf[127+ UIP_LLH_LEN +1];

/**
 * \brief   Perform any setup needed
 */
#if !RF230BB
 struct mac_driver * pmac;
#endif
void mac_ethernetSetup(void)
{
  usbstick_mode.sicslowpan = 1;
  usbstick_mode.sendToRf = 1;
  usbstick_mode.translate = 1;
  usbstick_mode.debugOn= 1;
  usbstick_mode.raw = 0;
  usbstick_mode.sneeze=0;

#if !RF230BB
  sicslowinput = pinput;

  pmac = sicslowmac_get_driver();
  pmac->set_receive_function(mac_ethhijack);
  sicslowmac_snifferhook = mac_ethhijack_nondata;
#endif
}


/**
 * \brief   Take a packet received over the ethernet link, and send it
 * out over 802.15.4
 */
void mac_ethernetToLowpan(uint8_t * ethHeader)
{
  //Dest address
  uip_lladdr_t destAddr;
  uip_lladdr_t *destAddrPtr = NULL;

  PRINTF("Packet type: 0x%04x\n\r", uip_ntohs(((struct uip_eth_hdr *) ethHeader)->type));

   //RUM doesn't support sending data
   #if UIP_CONF_USE_RUM
   return;
   #endif

  /* In sniffer or sneezr mode we don't ever send anything */
  if ((usbstick_mode.sendToRf == 0) || (usbstick_mode.sneeze != 0)) {
    uip_len = 0;
    return;
  }


  /* If not IPv6 we don't do anything. Disable ipv4 on the interface to prevent possible hangs from discovery packet flooding */
  if (((struct uip_eth_hdr *) ethHeader)->type != UIP_HTONS(UIP_ETHTYPE_IPV6)) {
    PRINTF("eth2low: Dropping packet w/type=0x%04x\n",uip_ntohs(((struct uip_eth_hdr *) ethHeader)->type));
  //      printf("!ipv6");
#if !RF230BB
    usb_eth_stat.txbad++;
#endif
    uip_len = 0;
    return;
  }

  /* IPv6 uses 33-33-xx-xx-xx-xx prefix for multicast ND stuff */
  if ( (((struct uip_eth_hdr *) ethHeader)->dest.addr[0] == 0x33) &&
       (((struct uip_eth_hdr *) ethHeader)->dest.addr[1] == 0x33) )
  {
    PRINTF("eth2low: Ethernet multicast packet received\n\r");
    ;//Do Nothing
  } else if ( (((struct uip_eth_hdr *) ethHeader)->dest.addr[0] == 0xFF) &&
            (((struct uip_eth_hdr *) ethHeader)->dest.addr[1] == 0xFF) &&
            (((struct uip_eth_hdr *) ethHeader)->dest.addr[2] == 0xFF) &&
            (((struct uip_eth_hdr *) ethHeader)->dest.addr[3] == 0xFF) &&
            (((struct uip_eth_hdr *) ethHeader)->dest.addr[4] == 0xFF) &&
            (((struct uip_eth_hdr *) ethHeader)->dest.addr[5] == 0xFF) ) {
    /* IPv6 does not use broadcast addresses, hence this should not happen */
    PRINTF("eth2low: Dropping broadcast packet\n\r");
#if !RF230BB
    usb_eth_stat.txbad++;
#endif
    uip_len = 0;
    return;
  } else {

  /* Simple Address Translation */
  if(memcmp((uint8_t *)&simple_trans_ethernet_addr, &(((struct uip_eth_hdr *) ethHeader)->dest.addr[0]), 6) == 0) {
#if UIP_CONF_IPV6
        //Addressed to us: make 802.15.4 address from IPv6 Address
        destAddr.addr[0] = UIP_IP_BUF->destipaddr.u8[8] ^ 0x02;
        destAddr.addr[1] = UIP_IP_BUF->destipaddr.u8[9];
        destAddr.addr[2] = UIP_IP_BUF->destipaddr.u8[10];
        destAddr.addr[3] = UIP_IP_BUF->destipaddr.u8[11];
        destAddr.addr[4] = UIP_IP_BUF->destipaddr.u8[12];
        destAddr.addr[5] = UIP_IP_BUF->destipaddr.u8[13];
        destAddr.addr[6] = UIP_IP_BUF->destipaddr.u8[14];
        destAddr.addr[7] = UIP_IP_BUF->destipaddr.u8[15];
#else
                //Not intended to be functional, but allows ip4 build without errors.
        destAddr.addr[0] = UIP_IP_BUF->destipaddr.u8[0] ^ 0x02;
        destAddr.addr[1] = UIP_IP_BUF->destipaddr.u8[1];
        destAddr.addr[2] = UIP_IP_BUF->destipaddr.u8[2];
        destAddr.addr[3] = UIP_IP_BUF->destipaddr.u8[3];
        destAddr.addr[4] = UIP_IP_BUF->destipaddr.u8[0];
        destAddr.addr[5] = UIP_IP_BUF->destipaddr.u8[1];
        destAddr.addr[6] = UIP_IP_BUF->destipaddr.u8[2];
        destAddr.addr[7] = UIP_IP_BUF->destipaddr.u8[3];

#endif

        destAddrPtr = &destAddr;
  }
#if UIP_CONF_SIMPLE_JACKDAW_ADDR_TRANS
  else {
        //Not addressed to us
        uip_len = 0;
        return;
  }
#else

    /* Complex Address Translation */
    PRINTF("eth2low: Addressed packet received... ");
    //Check this returns OK
    if (mac_createSicslowpanLongAddr( &(((struct uip_eth_hdr *) ethHeader)->dest.addr[0]), &destAddr) == 0) {
      PRINTF(" translation failed\n\r");
#if !RF230BB
      usb_eth_stat.txbad++;
#endif
      uip_len = 0;
      return;
    }
    PRINTF(" translated OK\n\r");
    destAddrPtr = &destAddr;
#endif /* UIP_CONF_SIMPLE_JACKDAW_ADDR_TRANS */


  }

  //Remove header from length before passing onward
  uip_len -= UIP_LLH_LEN;

  //Some IP packets have link layer in them, need to change them around!
  if (usbstick_mode.translate) {
#if DEBUG
    uint8_t transReturn = mac_translateIPLinkLayer(ll_802154_type);
    PRINTF("IPTranslation: returns %d\n\r", transReturn);
#else
    mac_translateIPLinkLayer(ll_802154_type);
#endif
  }

#if UIP_CONF_IPV6
/* Send the packet to the uip6 stack if it exists, else send to 6lowpan */
#if UIP_CONF_IPV6_RPL
/* Save the destination address, to trap ponging it back to the interface */
  uip_ipaddr_copy(&last_sender, &UIP_IP_BUF->srcipaddr);
  tcpip_input();
#else
//  PRINTF("Input from %x %x %x %x %x %x %x %x\n",UIP_IP_BUF->srcipaddr.u8[0],UIP_IP_BUF->srcipaddr.u8[1],UIP_IP_BUF->srcipaddr.u8[2],UIP_IP_BUF->srcipaddr.u8[3],UIP_IP_BUF->srcipaddr.u8[4],UIP_IP_BUF->srcipaddr.u8[5],UIP_IP_BUF->srcipaddr.u8[6],UIP_IP_BUF->srcipaddr.u8[7]);
//  PRINTF("Output to %x %x %x %x %x %x %x %x\n",destAddr.addr[0],destAddr.addr[1],destAddr.addr[2],destAddr.addr[3],destAddr.addr[4],destAddr.addr[5],destAddr.addr[6],destAddr.addr[7]);
  tcpip_output(destAddrPtr);
#endif
#else  /* UIP_CONF_IPV6 */
  tcpip_output();    //Allow non-ipv6 builds (Hello World) 
#endif /* UIP_CONF_IPV6 */

#if !RF230BB
  usb_eth_stat.txok++;
#endif
  uip_len = 0;

}


/**
 * \brief Take a packet received over the 802.15.4 link, and send it
 * out over ethernet, performing any translations needed.
 */
void mac_LowpanToEthernet(void)
{
#if !RF230BB
  parsed_frame = sicslowmac_get_frame();
#endif

  //Setup generic ethernet stuff
  ETHBUF(uip_buf)->type = uip_htons(UIP_ETHTYPE_IPV6);

  //Check for broadcast message
  
#if RF230BB
  if(rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER), &rimeaddr_null)) {
//  if(rimeaddr_cmp((const rimeaddr_t *)destAddr, &rimeaddr_null)) {
#else
  if(  ( parsed_frame->fcf->destAddrMode == SHORTADDRMODE) &&
       ( parsed_frame->dest_addr->addr16 == 0xffff) ) {
#endif
    ETHBUF(uip_buf)->dest.addr[0] = 0x33;
    ETHBUF(uip_buf)->dest.addr[1] = 0x33;

#if UIP_CONF_IPV6
    ETHBUF(uip_buf)->dest.addr[2] = UIP_IP_BUF->destipaddr.u8[12];
    ETHBUF(uip_buf)->dest.addr[3] = UIP_IP_BUF->destipaddr.u8[13];
    ETHBUF(uip_buf)->dest.addr[4] = UIP_IP_BUF->destipaddr.u8[14];
    ETHBUF(uip_buf)->dest.addr[5] = UIP_IP_BUF->destipaddr.u8[15];
#else
        //Not intended to be functional, but allows ip4 build without errors.
    ETHBUF(uip_buf)->dest.addr[2] = UIP_IP_BUF->destipaddr.u8[0];
    ETHBUF(uip_buf)->dest.addr[3] = UIP_IP_BUF->destipaddr.u8[1];
    ETHBUF(uip_buf)->dest.addr[4] = UIP_IP_BUF->destipaddr.u8[2];
    ETHBUF(uip_buf)->dest.addr[5] = UIP_IP_BUF->destipaddr.u8[3];
#endif
  } else {
        //Otherwise we have a real address
        mac_createEthernetAddr((uint8_t *) &(ETHBUF(uip_buf)->dest.addr[0]),
                        (uip_lladdr_t *)packetbuf_addr(PACKETBUF_ADDR_RECEIVER));
  }

#if !UIP_CONF_SIMPLE_JACKDAW_ADDR_TRANS
  //Source ethernet depends on node
  if(!mac_createEthernetAddr(
    (uint8_t *) &(ETHBUF(uip_buf)->src.addr[0]),
    (uip_lladdr_t *)packetbuf_addr(PACKETBUF_ADDR_SENDER)
  ))
#endif

  {
    mac_createDefaultEthernetAddr((uint8_t *) &(ETHBUF(uip_buf)->src.addr[0]));
  }

  //We only do address translation in network mode!
  if (usbstick_mode.translate) {
    //Some IP packets have link layer in them, need to change them around!
    mac_translateIPLinkLayer(ll_8023_type);
  }
 
#if UIP_CONF_IPV6_RPL
/* We won't play ping-pong with the host! */
    if(uip_ipaddr_cmp(&last_sender, &UIP_IP_BUF->srcipaddr)) {
        PRINTF("siclow_ethernet: Destination off-link but no route\n");
        uip_len=0;
        return;
    }
#endif

  PRINTF("Low2Eth: Sending packet to ethernet\n\r");

  uip_len += UIP_LLH_LEN;

  usb_eth_send(uip_buf, uip_len, 1);
#if !RF230BB
  usb_eth_stat.rxok++;
#endif
  uip_len = 0;
}

/**
 * \brief Translate IP packet's possible link-layer addresses, passing
 *        the message to the appropriate higher level function for this
 *        packet (aka: ICMP)
 * \param target The target we want to end up with - either ll_8023_type
 *        for ethernet, or ll_802154_type for 802.15.4
 * \return    Returns how successful the translation was
 * \retval 0  Addresses, if present, were translated.
 * \retval <0 Negative return values indicate various errors, as defined
 *            by the higher level function.
 */
int8_t mac_translateIPLinkLayer(lltype_t target)
{

#if UIP_LLADDR_LEN == 8
  if (UIP_IP_BUF->proto == UIP_PROTO_ICMP6) {
    PRINTF("eth2low: ICMP Message detected\n\r");
    return mac_translateIcmpLinkLayer(target);
  }
  return 0;
#else
  return 1;
#endif

}

#include "net/uip-icmp6.h"
#include "net/uip-nd6.h"

typedef struct {
  uint8_t type;
  uint8_t length;
  uint8_t data[16];
} icmp_opts_t;

#define UIP_ICMP_BUF     ((struct uip_icmp_hdr *)&uip_buf[UIP_LLH_LEN + UIP_IPH_LEN])
#define UIP_ICMP_OPTS(x) ((icmp_opts_t *)&uip_buf[UIP_LLH_LEN + UIP_IPH_LEN + x])

void slide(uint8_t * data, uint8_t length, int16_t slide);

/**
 * \brief Translate the link-layer (L2) addresses in an ICMP packet.
 *        This will just be NA/NS/RA/RS packets currently.
 * \param target The target we want to end up with - either ll_8023_type
 *        for ethernet, or ll_802154_type for 802.15.4
 * \return       Returns how successful the translation was
 * \retval 0     Addresses, if present, were translated.
 * \retval -1    ICMP message was unknown type, nothing done.
 * \retval -2    ICMP Length does not make sense?
 * \retval -3    Unknown 'target' type
 */
int8_t mac_translateIcmpLinkLayer(lltype_t target)
{
  uint16_t icmp_opt_offset = 0;
  int16_t len = UIP_IP_BUF->len[1] | (UIP_IP_BUF->len[0] << 8);

  uint16_t iplen;

  uint8_t i;

  int16_t sizechange;

  uint8_t llbuf[16];

  //Figure out offset to start of options
  switch(UIP_ICMP_BUF->type) {
    case ICMP6_NS:
    case ICMP6_NA:
      icmp_opt_offset = 24;
      break;

    case ICMP6_RS:
      icmp_opt_offset = 8;
      break;

    case ICMP6_RA:
      icmp_opt_offset = 16;
      break;

    case ICMP6_REDIRECT:
      icmp_opt_offset = 40;
      break;

      /** Things without link-layer */
    case ICMP6_DST_UNREACH:
    case ICMP6_PACKET_TOO_BIG:
    case ICMP6_TIME_EXCEEDED:   
    case ICMP6_PARAM_PROB:
    case ICMP6_ECHO_REQUEST:  
    case ICMP6_ECHO_REPLY: 
      return 0;
      break;

    default:
      return -1;
  }

  //Figure out length of options
  len -= icmp_opt_offset;

  //Sanity check
  if (len < 8) return -2; 

  //While we have options to do...
  while (len >= 8){
    
    //If we have one of these, we have something useful!
    if (((UIP_ICMP_OPTS(icmp_opt_offset)->type) == UIP_ND6_OPT_SLLAO) || 
        ((UIP_ICMP_OPTS(icmp_opt_offset)->type) == UIP_ND6_OPT_TLLAO) ) {
      
      /* Shrinking the buffer may thrash things, so we store the old
         link-layer address */
      for(i = 0; i < (UIP_ICMP_OPTS(icmp_opt_offset)->length*8 - 2); i++) {
        llbuf[i] = UIP_ICMP_OPTS(icmp_opt_offset)->data[i];
      }

      //Shrink/grow buffer as needed
      if (target == ll_802154_type) {
        //Current is 802.3, Hence current link-layer option is 6 extra bytes
        sizechange = 8;
        slide(UIP_ICMP_OPTS(icmp_opt_offset)->data + 6, len - 6, sizechange);
      } else if (target == ll_8023_type) {
        /* Current is 802.15.4, Hence current link-layer option is 14 extra
         * bytes.
         * (Actual LL is 8 bytes, but total option length is in multiples of
         * 8 Bytes, hence 8 + 2 = 10. Closest is 16 bytes, then 16 bytes for
         * total optional length - 2 bytes for type + length leaves 14 )
         */
        sizechange = -8;
        slide(UIP_ICMP_OPTS(icmp_opt_offset)->data + 14, len - 14, sizechange);
      } else {
        return -3; //Uh-oh!
      }
      
      //Translate addresses
      if (target == ll_802154_type) {
        mac_createSicslowpanLongAddr(llbuf, (uip_lladdr_t *)UIP_ICMP_OPTS(icmp_opt_offset)->data);
      } else {
#if !UIP_CONF_SIMPLE_JACKDAW_ADDR_TRANS
        if(!mac_createEthernetAddr(UIP_ICMP_OPTS(icmp_opt_offset)->data, (uip_lladdr_t *)llbuf))
#endif
            mac_createDefaultEthernetAddr(UIP_ICMP_OPTS(icmp_opt_offset)->data);
      }
      
      //Adjust the length
      if (target == ll_802154_type) {
        UIP_ICMP_OPTS(icmp_opt_offset)->length = 2;
      } else {
        UIP_ICMP_OPTS(icmp_opt_offset)->length = 1;
      }

      //Adjust the IP header length, as well as uIP length
      iplen = UIP_IP_BUF->len[1] | (UIP_IP_BUF->len[0]<<8);
      iplen += sizechange;
      len += sizechange;
      
      UIP_IP_BUF->len[1] = (uint8_t)iplen;
      UIP_IP_BUF->len[0] = (uint8_t)(iplen >> 8);

      uip_len += sizechange;

      //We broke ICMP checksum, be sure to fix that
      UIP_ICMP_BUF->icmpchksum = 0;
#if UIP_CONF_IPV6   //allow non ipv6 builds
      UIP_ICMP_BUF->icmpchksum = ~uip_icmp6chksum();
#endif

      //Finally set up next run in while loop
      len -= 8 * UIP_ICMP_OPTS(icmp_opt_offset)->length;
      icmp_opt_offset += 8 * UIP_ICMP_OPTS(icmp_opt_offset)->length;
    } else {
          
      //Not an option we care about, ignore it
      len -= 8 * UIP_ICMP_OPTS(icmp_opt_offset)->length;
              
      //This shouldn't happen!
      if (UIP_ICMP_OPTS(icmp_opt_offset)->length == 0) {
        PRINTF("Option in ND packet has length zero, error?\n\r");
        len = 0;
      }

      icmp_opt_offset += 8 * UIP_ICMP_OPTS(icmp_opt_offset)->length;
      
    } //If ICMP_OPT is one we care about
   
  } //while(len >= 8)

  return 0;

}


/**
 * \brief Create a 802.15.4 long address from a 802.3 address
 * \param ethernet   Pointer to ethernet address
 * \param lowpan     Pointer to 802.15.4 address
 */
uint8_t mac_createSicslowpanLongAddr(uint8_t * ethernet, uip_lladdr_t * lowpan)
{
#if UIP_CONF_AUTO_SUBSTITUTE_LOCAL_MAC_ADDR
  //Special case - if the address is our address, we just copy over what we know to be
  //our 802.15.4 address
  if (memcmp((uint8_t *)&usb_ethernet_addr, ethernet, 6) == 0)
  {
    memcpy((uint8_t *)lowpan, &macLongAddr, UIP_LLADDR_LEN);
    return 1;
  }
#endif

#if UIP_CONF_SIMPLE_JACKDAW_ADDR_TRANS

  //Easy does it!
  lowpan->addr[0] = ethernet[0];
  lowpan->addr[1] = ethernet[1];
  lowpan->addr[2] = ethernet[2];
  lowpan->addr[3] = 0xff;
  lowpan->addr[4] = 0xfe;
  lowpan->addr[5] = ethernet[3];
  lowpan->addr[6] = ethernet[4];
  lowpan->addr[7] = ethernet[5];

#else //!UIP_CONF_SIMPLE_JACKDAW_ADDR_TRANS

  uint8_t index;

#if UIP_LLADDR_LEN == 8
  //Check if translate bit is set, hence we have to look up the prefix
  if((ethernet[0]&(TRANSLATE_BIT_MASK|MULTICAST_BIT_MASK|LOCAL_BIT_MASK)) == (TRANSLATE_BIT_MASK|LOCAL_BIT_MASK)) {
    //Get top bits
    index = ethernet[0] >> 3;

    //Copy over prefix
    lowpan->addr[0] = prefixBuffer[index][0];
    lowpan->addr[1] = prefixBuffer[index][1];
    lowpan->addr[2] = prefixBuffer[index][2];
    lowpan->addr[3] = ethernet[1];
    lowpan->addr[4] = ethernet[2];

    //Check this is plausible...
    if (index >= prefixCounter)
        return 0;
  } else {
    lowpan->addr[0] = ethernet[0];
    lowpan->addr[1] = ethernet[1];
    lowpan->addr[2] = ethernet[2];
    lowpan->addr[3] = 0xff;
    lowpan->addr[4] = 0xfe;
  }

  lowpan->addr[5] = ethernet[3];
  lowpan->addr[6] = ethernet[4];
  lowpan->addr[7] = ethernet[5];

#else //UIP_LLADDR != 8
    // Not sure when we would ever hit this case...
        uint8_t i;
        for(i = 0; i < UIP_LLADDR_LEN; i++) {
                lowpan->addr[i] = ethernet[i];
        }
#endif //UIP_LLADDR == 8

#endif //UIP_CONF_SIMPLE_JACKDAW_ADDR_TRANS

  return 1;
}


/**
 * \brief Create a 802.3 address from a 802.15.4 long address
 * \param ethernet   Pointer to ethernet address
 * \param lowpan     Pointer to 802.15.4 address
 */
uint8_t mac_createEthernetAddr(uint8_t * ethernet, uip_lladdr_t * lowpan)
{
#if UIP_CONF_AUTO_SUBSTITUTE_LOCAL_MAC_ADDR
        //Special case - if the address is our address, we just copy over what we know to be
        //our 802.3 address
        if (memcmp((uint8_t *)&macLongAddr, (uint8_t *)lowpan, UIP_LLADDR_LEN) == 0) {
                usb_eth_get_mac_address(ethernet);
                return 1;
        } 
#endif  

#if UIP_CONF_SIMPLE_JACKDAW_ADDR_TRANS

  /** Just copy over 6 bytes **/
    ethernet[0] = lowpan->addr[0];
    ethernet[1] = lowpan->addr[1];
    ethernet[2] = lowpan->addr[2];
    ethernet[3] = lowpan->addr[5];
    ethernet[4] = lowpan->addr[6];
    ethernet[5] = lowpan->addr[7];

#else //!UIP_CONF_SIMPLE_JACKDAW_ADDR_TRANS

  uint8_t index = 0;
  uint8_t i;

#if UIP_LLADDR_LEN == 8

        //Check if we need to do anything:
        if ((lowpan->addr[3] == 0xff) && (lowpan->addr[4] == 0xfe) &&
          ((lowpan->addr[0] & TRANSLATE_BIT_MASK) == 0) &&
          ((lowpan->addr[0] & MULTICAST_BIT_MASK) == 0) &&
          (lowpan->addr[0] & LOCAL_BIT_MASK)) {
                
    /** Nope: just copy over 6 bytes **/
      ethernet[0] = lowpan->addr[0];
          ethernet[1] = lowpan->addr[1];
          ethernet[2] = lowpan->addr[2];
          ethernet[3] = lowpan->addr[5];
          ethernet[4] = lowpan->addr[6];
          ethernet[5] = lowpan->addr[7];
          
        
  } else {

    /** Yes: need to store prefix **/
    for (i = 0; i < prefixCounter; i++) {       
      //Check the current prefix - if it fails, check next one
      if ((lowpan->addr[0] == prefixBuffer[i][0]) &&
         (lowpan->addr[1] == prefixBuffer[i][1]) &&
         (lowpan->addr[2] == prefixBuffer[i][2])) {
        break;
      }
  }
    index = i;

                if (index >= PREFIX_BUFFER_SIZE) {
                        // Overflow. Fall back to simple translation.
                        // TODO: Implement me!
                        ethernet[0] = lowpan->addr[0];
                        ethernet[1] = lowpan->addr[1];
                        ethernet[2] = lowpan->addr[2];
                        ethernet[3] = lowpan->addr[5];
                        ethernet[4] = lowpan->addr[6];
                        ethernet[5] = lowpan->addr[7];
                        return 0;
                } else {        
                        //Are we making a new one?
                        if (index == prefixCounter) {
                                prefixCounter++;
                                prefixBuffer[index][0] = lowpan->addr[0];
                                prefixBuffer[index][1] = lowpan->addr[1];
                                prefixBuffer[index][2] = lowpan->addr[2];
                        }

                        //Create ethernet MAC address now
                        ethernet[0] = TRANSLATE_BIT_MASK | LOCAL_BIT_MASK | (index << 3);
                        ethernet[1] = lowpan->addr[3];
                        ethernet[2] = lowpan->addr[4];
                        ethernet[3] = lowpan->addr[5];
                        ethernet[4] = lowpan->addr[6];
                        ethernet[5] = lowpan->addr[7];
                }
        }

#else //UIP_LLADDR_LEN != 8
        // Not sure when we would ever hit this case...
    //Create ethernet MAC address now
        for(i = 0; i < UIP_LLADDR_LEN; i++) {
                ethernet[i] = lowpan->addr[i];
        }
#endif //UIP_LLADDR_LEN == 8

#endif //UIP_CONF_SIMPLE_JACKDAW_ADDR_TRANS

  return 1;
}
/**
 * \brief Create a 802.3 address (default)
 * \param ethernet   Pointer to ethernet address
 */
uint8_t mac_createDefaultEthernetAddr(uint8_t * ethernet)
{
  memcpy(ethernet, &simple_trans_ethernet_addr, 6);
  return 1;
}
/**
 * \brief        Slide the pointed to memory up a certain amount,
 *               growing/shrinking a buffer
 * \param data   Pointer to start of data buffer
 * \param length Length of the data buffer
 * \param slide  How many bytes to slide the buffer up in memory (if +) or
 *               down in memory (if -)
 */
void slide(uint8_t * data, uint8_t length, int16_t slide)
{
  //Sanity checks
  if (!length) return;
  if (!slide) return;

  uint8_t i = 0;

  while(length) {
    length--;

    //If we are sliding up, we do from the top of the buffer down
    if (slide > 0) {
      *(data + length + slide) = *(data + length);      

      //If we are sliding down, we do from the bottom of the buffer up
    } else {
      *(data + slide + i) = *(data + i);
    }
    
    i++;
  }
}

//#define ETHBUF(x) ((struct uip_eth_hdr *)x)
//#define UIP_IP_BUF   ((struct uip_ip_hdr *)&uip_buf[UIP_LLH_LEN])

void
mac_log_802_15_4_tx(const uint8_t* buffer, size_t total_len) {
  if (usbstick_mode.raw != 0) {
    uint8_t sendlen;

        static uint8_t raw_buf[127+ UIP_LLH_LEN +1];

  /* Get the raw frame */
    memcpy(&raw_buf[UIP_LLH_LEN], buffer, total_len);
    sendlen = total_len;

  /* Setup generic ethernet stuff */
    ETHBUF(raw_buf)->type = uip_htons(0x809A);  //UIP_ETHTYPE_802154 0x809A
 
  /* Check for broadcast message */
    if(rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER), &rimeaddr_null)) {
      ETHBUF(raw_buf)->dest.addr[0] = 0x33;
      ETHBUF(raw_buf)->dest.addr[1] = 0x33;
      ETHBUF(raw_buf)->dest.addr[2] = 0x00;
      ETHBUF(raw_buf)->dest.addr[3] = 0x00;
      ETHBUF(raw_buf)->dest.addr[4] = 0x80;
      ETHBUF(raw_buf)->dest.addr[5] = 0x9A;

/*
      ETHBUF(raw_buf)->dest.addr[2] = UIP_IP_BUF->destipaddr.u8[12];
      ETHBUF(raw_buf)->dest.addr[3] = UIP_IP_BUF->destipaddr.u8[13];
      ETHBUF(raw_buf)->dest.addr[4] = UIP_IP_BUF->destipaddr.u8[14];
      ETHBUF(raw_buf)->dest.addr[5] = UIP_IP_BUF->destipaddr.u8[15];
*/
    } else {
  /* Otherwise we have a real address */  
      mac_createEthernetAddr((uint8_t *) &(ETHBUF(raw_buf)->dest.addr[0]),
          (uip_lladdr_t *)packetbuf_addr(PACKETBUF_ADDR_RECEIVER));
    }

//    mac_createEthernetAddr((uint8_t *) &(ETHBUF(raw_buf)->src.addr[0]),(uip_lladdr_t *)&uip_lladdr.addr);
        mac_createDefaultEthernetAddr((uint8_t *) &(ETHBUF(raw_buf)->src.addr[0]));

    sendlen += UIP_LLH_LEN;
    usb_eth_send(raw_buf, sendlen, 0);
  }
}

void
mac_log_802_15_4_rx(const uint8_t* buf, size_t len) {
  if (usbstick_mode.raw != 0) {
    uint8_t sendlen;

  /* Get the raw frame */
    memcpy(&raw_buf[UIP_LLH_LEN], buf, len);
    sendlen = len;

  /* Setup generic ethernet stuff */
    ETHBUF(raw_buf)->type = uip_htons(0x809A);  //UIP_ETHTYPE_802154 0x809A
  
  /* Check for broadcast message */
    if(rimeaddr_cmp(packetbuf_addr(PACKETBUF_ADDR_RECEIVER), &rimeaddr_null)) {
      ETHBUF(raw_buf)->dest.addr[0] = 0x33;
      ETHBUF(raw_buf)->dest.addr[1] = 0x33;
      ETHBUF(raw_buf)->dest.addr[2] = 0x00;
      ETHBUF(raw_buf)->dest.addr[3] = 0x00;
      ETHBUF(raw_buf)->dest.addr[4] = 0x80;
      ETHBUF(raw_buf)->dest.addr[5] = 0x9A;
/*
      ETHBUF(raw_buf)->dest.addr[2] = UIP_IP_BUF->destipaddr.u8[12];
      ETHBUF(raw_buf)->dest.addr[3] = UIP_IP_BUF->destipaddr.u8[13];
      ETHBUF(raw_buf)->dest.addr[4] = UIP_IP_BUF->destipaddr.u8[14];
      ETHBUF(raw_buf)->dest.addr[5] = UIP_IP_BUF->destipaddr.u8[15];
*/
    } else {
  /* Otherwise we have a real address */  
      mac_createEthernetAddr((uint8_t *) &(ETHBUF(raw_buf)->dest.addr[0]),
          (uip_lladdr_t *)packetbuf_addr(PACKETBUF_ADDR_RECEIVER));
    }

//    mac_createEthernetAddr((uint8_t *) &(ETHBUF(raw_buf)->src.addr[0]),(uip_lladdr_t *)&uip_lladdr.addr);
        mac_createDefaultEthernetAddr((uint8_t *) &(ETHBUF(raw_buf)->src.addr[0]));

    sendlen += UIP_LLH_LEN;
    usb_eth_send(raw_buf, sendlen, 0);
  }
}
/* The rf230bb send driver may call this routine via  RF230BB_HOOK_IS_SEND_ENABLED */
bool
mac_is_send_enabled(void) {
  if ((usbstick_mode.sendToRf == 0) || (usbstick_mode.sneeze != 0)) return 0;
  return 1;
//return usbstick_mode.sendToRf;
}

/** @} */



/** @} */


#if !RF230BB
/*--------------------------------------------------------------------*/
/** \brief Process a received 6lowpan packet. Hijack function.
 *  \param r The MAC layer
 *
 *  The 6lowpan packet is put in packetbuf by the MAC. This routine calls
 *  any other needed layers (either 6lowpan, or just raw ethernet dump)
 */
void mac_ethhijack(const struct mac_driver *r)
{
        if (usbstick_mode.raw) {
                mac_802154raw(r);
        }
                
        if (usbstick_mode.sicslowpan) {

#if UIP_CONF_USE_RUM
        if (parsed_frame->payload[4]) { /* RUM 6lowpan frame type */
#endif
                sicslowinput(r);        
#if UIP_CONF_USE_RUM
        }
#endif          
                
                
        }

}

void mac_ethhijack_nondata(const struct mac_driver *r)
{
        if (usbstick_mode.raw)
                mac_802154raw(r);
}


/*--------------------------------------------------------------------*/
/*--------------------------------------------------------------------*/
/** \brief Logs a sent 6lowpan frame
 *
 *  This routine passes a frame 
 *  directly to the ethernet layer without decompressing.
 */
void mac_logTXtoEthernet(frame_create_params_t *p,frame_result_t *frame_result)
{
        mac_log_802_15_4_tx(frame_result->frame, frame_result->length);
}


/*--------------------------------------------------------------------*/
/** \brief Process a received 6lowpan packet. 
 *  \param r The MAC layer
 *
 *  The 6lowpan packet is put in packetbuf by the MAC. This routine passes
 *  it directly to the ethernet layer without decompressing.
 */
void mac_802154raw(const struct mac_driver *r) { 
        mac_log_802_15_4_tx(radio_frame_data(), radio_frame_length());
}

#endif /* !RF230BB */