/**
 * \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 && !RF212BB
  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 || RF212BB
  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;
  if (usbstick_mode.raw == 0)
	  usb_eth_send(uip_buf, uip_len, 1);
#if !RF230BB && !RF212BB
  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)
Example #2
0
/**
 * \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
 */
static int8_t
mac_translateIcmpLinkLayer(lltype_t target)
{
    uint16_t icmp_opt_offset=0,
             sizechange,
             iplen;
    int16_t  len = UIP_IP_BUF->len[1] | (UIP_IP_BUF->len[0] << 8);
    uint8_t  i,
             llbuf[6];

    // 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
                mac_createEthernetAddr(UIP_ICMP_OPTS(icmp_opt_offset)->data, (uip_lladdr_t *)llbuf);

            // 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;
            UIP_ICMP_BUF->icmpchksum = ~uip_icmp6chksum();

            // 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)
                len = 0;

            icmp_opt_offset += 8 * UIP_ICMP_OPTS(icmp_opt_offset)->length;
        }
    }