Exemplo n.º 1
0
/**
\brief Send a packet originating at this mote.

This function is called by an upper layer, and only concerns packets originated
at this mote.

\param[in,out] msg Packet to send.
*/
owerror_t forwarding_send(OpenQueueEntry_t* msg) {
   ipv6_header_iht      ipv6_header;
   rpl_option_ht        rpl_option;
   open_addr_t*         myprefix;
   open_addr_t*         myadd64;
   uint32_t             flow_label = 0;
   
   // take ownership over the packet
   msg->owner                = COMPONENT_FORWARDING;
   
   // retrieve my prefix and EUI64
   myprefix                  = idmanager_getMyID(ADDR_PREFIX);
   myadd64                   = idmanager_getMyID(ADDR_64B);
   
   // set source address (me)
   msg->l3_sourceAdd.type=ADDR_128B;
   memcpy(&(msg->l3_sourceAdd.addr_128b[0]),myprefix->prefix,8);
   memcpy(&(msg->l3_sourceAdd.addr_128b[8]),myadd64->addr_64b,8);
   
   // initialize IPv6 header
   memset(&ipv6_header,0,sizeof(ipv6_header_iht));
   
   // Set hop limit to the default in-network value as this packet is being
   // sent from upper layer. This is done here as send_internal() is used by
   // forwarding of packets as well which carry a hlim. This value is required
   // to be set to a value as the following function can decrement it.
   ipv6_header.hop_limit     = IPHC_DEFAULT_HOP_LIMIT;
   
   // create the RPL hop-by-hop option

   forwarding_createRplOption(
      &rpl_option,      // rpl_option to fill in
      0x00              // flags
   );

#ifdef FLOW_LABEL_RPL_DOMAIN
   forwarding_createFlowLabel(&flow_label,0x00);
#endif

   return forwarding_send_internal_RoutingTable(
      msg,
      &ipv6_header,
      &rpl_option,
      &flow_label,
      PCKTSEND
   );
}
Exemplo n.º 2
0
/**
\brief Indicates a packet was received.

\param[in,out] msg               The packet just sent.
\param[in]     ipv6_header       The information contained in the IPv6 header.
\param[in]     ipv6_hop_header   The hop-by-hop header present in the packet.
\param[in]     rpl_option        The hop-by-hop options present in the packet.
*/
void forwarding_receive(
      OpenQueueEntry_t*      msg,
      ipv6_header_iht*       ipv6_header,
      ipv6_hopbyhop_iht*     ipv6_hop_header,
      rpl_option_ht*         rpl_option
   ) {
   uint8_t flags;
   uint16_t senderRank;
   
   // take ownership
   msg->owner                     = COMPONENT_FORWARDING;
   
   // determine L4 protocol
   if (ipv6_header->next_header==IANA_IPv6HOPOPT){
      // get information from ipv6_hop_header
      
      msg->l4_protocol            = ipv6_hop_header->nextHeader;
      msg->l4_protocol_compressed = ipv6_hop_header->next_header_compressed;
   } else {
      // get information from ipv6_header
      
      msg->l4_protocol            = ipv6_header->next_header;
      msg->l4_protocol_compressed = ipv6_header->next_header_compressed;
   }
   
   // populate packets metadata with L3 information
   memcpy(&(msg->l3_destinationAdd),&ipv6_header->dest,sizeof(open_addr_t));
   memcpy(&(msg->l3_sourceAdd),     &ipv6_header->src, sizeof(open_addr_t));
   
   if (
         (
            idmanager_isMyAddress(&ipv6_header->dest)
            ||
            packetfunctions_isBroadcastMulticast(&ipv6_header->dest)
         )
         &&
         ipv6_header->next_header!=IANA_IPv6ROUTE
      ) {
      // this packet is for me, no source routing header.

      // indicate received packet to upper layer
      switch(msg->l4_protocol) {
         case IANA_TCP:
            opentcp_receive(msg);
            break;
         case IANA_UDP:
            openudp_receive(msg);
            break;
         case IANA_ICMPv6:
            icmpv6_receive(msg);
            break;
         default:
            
            // log error
            openserial_printError(
               COMPONENT_FORWARDING,ERR_WRONG_TRAN_PROTOCOL,
               (errorparameter_t)msg->l4_protocol,
               (errorparameter_t)1
            );
            
            // free packet
            openqueue_freePacketBuffer(msg);
      }
   } else {
      // this packet is not for me: relay
      
      // change the creator of the packet
      msg->creator = COMPONENT_FORWARDING;
      
      if (ipv6_header->next_header!=IANA_IPv6ROUTE) {
         // no source routing header present
         //check if flow label rpl header
    	 #ifdef FLOW_LABEL_RPL_DOMAIN             
             flags = (uint8_t)((uint32_t)((ipv6_header->flow_label)>>16)&0xFF);
             senderRank = (uint16_t)((uint32_t)(ipv6_header->flow_label)>>8)&0xFFFF;
             senderRank = senderRank*MINHOPRANKINCREASE;//shift it according to HopRank Increase
         #else
    	     flags = rpl_option->flags;
    	     senderRank = rpl_option->senderRank;
    	 #endif

         if ((flags & O_FLAG)!=0){
            // wrong direction
            
            // log error
            openserial_printError(
               COMPONENT_FORWARDING,
               ERR_WRONG_DIRECTION,
               (errorparameter_t)flags,
               (errorparameter_t)senderRank
            );
         }
         

         if (senderRank < neighbors_getMyDAGrank()){
            // loop
            
            // set flag
            #ifdef FLOW_LABEL_RPL_DOMAIN
        	    flags |= R_FLAG;
        	    ipv6_header->flow_label|= ((uint32_t)flags<<16);
            #else
        	    rpl_option->flags |= R_FLAG;
            #endif

            // log error
            openserial_printError(
               COMPONENT_FORWARDING,
               ERR_LOOP_DETECTED,
               (errorparameter_t) senderRank,
               (errorparameter_t) neighbors_getMyDAGrank()
            );
         }
         

         forwarding_createRplOption(rpl_option, rpl_option->flags);
         #ifdef FLOW_LABEL_RPL_DOMAIN
         // do not recreate flow label, relay the same but adding current flags
         //forwarding_createFlowLabel(&(ipv6_header->flow_label),flags);
         #endif
         // resend as if from upper layer
         if (
               forwarding_send_internal_RoutingTable(
                  msg,
                  ipv6_header,
                  rpl_option,
                  &(ipv6_header->flow_label),
                  PCKTFORWARD 
               )==E_FAIL
            ) {
            openqueue_freePacketBuffer(msg);
         }
      } else {
         // source routing header present
         
         if (forwarding_send_internal_SourceRouting(msg, ipv6_header)==E_FAIL) {
Exemplo n.º 3
0
/**
\brief Send a packet using the source rout to find the next hop.

\note This is always called for packets being forwarded.

How to process the routing header is detailed in
http://tools.ietf.org/html/rfc6554#page-9.

\param[in,out] msg             The packet to send.
\param[in]     ipv6_header     The packet's IPv6 header.
*/
owerror_t forwarding_send_internal_SourceRouting(OpenMote* self, 
    OpenQueueEntry_t* msg,
    ipv6_header_iht*  ipv6_outer_header,
    ipv6_header_iht*  ipv6_inner_header,
    rpl_option_ht*    rpl_option
    ) {
    uint8_t              temp_8b;
    uint8_t              type;
    uint8_t              next_type;
    uint8_t              size;
    uint8_t              next_size;
    uint8_t              hlen;
    open_addr_t          firstAddr;
    open_addr_t          nextAddr;
    open_addr_t          temp_prefix;
    open_addr_t          temp_addr64;
    
    uint8_t              rpi_length;
    uint8_t              flags;
    uint16_t             senderRank;
    
    uint8_t              RH3_copy[127];
    uint8_t              RH3_length;
    
    memset(&RH3_copy[0],0,127);
    RH3_length = 0;
    memcpy(&msg->l3_destinationAdd,&ipv6_inner_header->dest,sizeof(open_addr_t));
    memcpy(&msg->l3_sourceAdd,&ipv6_inner_header->src,sizeof(open_addr_t));
    
    // initial first Address by compression reference
    firstAddr.type = ADDR_128B;
    if (ipv6_outer_header->src.type != ADDR_NONE){
        if (rpl_option->rplInstanceID == 0){
 icmpv6rpl_getRPLDODAGid(self, &firstAddr.addr_128b[0]);
        }
    } else {
        memcpy(&firstAddr,&ipv6_inner_header->src,sizeof(open_addr_t));
    }
    
    hlen = 0;
    
    temp_8b = *((uint8_t*)(msg->payload)+hlen);
    type    = *((uint8_t*)(msg->payload)+hlen+1);
    
    hlen += 2;
    // get the first address
    switch(type){
    case RH3_6LOTH_TYPE_0:
        memcpy(&firstAddr.addr_128b[15],msg->payload+hlen,1);
        hlen += 1;
        break;
    case RH3_6LOTH_TYPE_1:
        memcpy(&firstAddr.addr_128b[14],msg->payload+hlen,2);
        hlen += 2;
        break;
    case RH3_6LOTH_TYPE_2:
        memcpy(&firstAddr.addr_128b[12],msg->payload+hlen,4);
        hlen += 4;
        break;
    case RH3_6LOTH_TYPE_3:
        memcpy(&firstAddr.addr_128b[8],msg->payload+hlen,8);
        hlen += 8;
        break;
    case RH3_6LOTH_TYPE_4:
        memcpy(&firstAddr.addr_128b[0],msg->payload+hlen,16);
        hlen += 16;
        break;
    }
    
 packetfunctions_ip128bToMac64b(self, &firstAddr,&temp_prefix,&temp_addr64);
    if (
 packetfunctions_sameAddress(self, &temp_prefix, idmanager_getMyID(self, ADDR_PREFIX)) &&
 packetfunctions_sameAddress(self, &temp_addr64, idmanager_getMyID(self, ADDR_64B))
    ){
        size = temp_8b & RH3_6LOTH_SIZE_MASK;
        if (size > 0){
            // there are at least 2 entries in the header, 
            // the router removes the first entry and decrements the Size (by 1) 
            size -= 1;
 packetfunctions_tossHeader(self, msg,hlen);
 packetfunctions_reserveHeaderSize(self, msg,2);
            msg->payload[0] = CRITICAL_6LORH | size;
            msg->payload[1] = type;
            // get next hop
            memcpy(&nextAddr,&firstAddr,sizeof(open_addr_t));
            switch(type){
            case RH3_6LOTH_TYPE_0:
                memcpy(&nextAddr.addr_128b[15],msg->payload+2,1);
                break;
            case RH3_6LOTH_TYPE_1:
                memcpy(&nextAddr.addr_128b[14],msg->payload+2,2);
                break;
            case RH3_6LOTH_TYPE_2:
                memcpy(&nextAddr.addr_128b[12],msg->payload+2,4);
                break;
            case RH3_6LOTH_TYPE_3:
                memcpy(&nextAddr.addr_128b[8],msg->payload+2,8);
                break;
            case RH3_6LOTH_TYPE_4:
                memcpy(&nextAddr.addr_128b[0],msg->payload+2,16);
                break;
            }
 packetfunctions_ip128bToMac64b(self, 
                &nextAddr,
                &temp_prefix,
                &msg->l2_nextORpreviousHop
            );
        } else {
            temp_8b   = *((uint8_t*)(msg->payload)+hlen);
            next_type = *((uint8_t*)(msg->payload)+hlen+1);
            if (
                (temp_8b & FORMAT_6LORH_MASK) == CRITICAL_6LORH &&
                next_type<=RH3_6LOTH_TYPE_4
            ) {
                // there is another RH3-6LoRH following, check the type
                if (next_type >= type){
 packetfunctions_tossHeader(self, msg,hlen);
                    // get next hop
                    memcpy(&nextAddr,&firstAddr,sizeof(open_addr_t));
                    switch(next_type){
                    case RH3_6LOTH_TYPE_0:
                        memcpy(&nextAddr.addr_128b[15],msg->payload+2,1);
                        break;
                    case RH3_6LOTH_TYPE_1:
                        memcpy(&nextAddr.addr_128b[14],msg->payload+2,2);
                        break;
                    case RH3_6LOTH_TYPE_2:
                        memcpy(&nextAddr.addr_128b[12],msg->payload+2,4);
                        break;
                    case RH3_6LOTH_TYPE_3:
                        memcpy(&nextAddr.addr_128b[8],msg->payload+2,8);
                        break;
                    case RH3_6LOTH_TYPE_4:
                        memcpy(&nextAddr.addr_128b[0],msg->payload+2,16);
                        break;
                    }
 packetfunctions_ip128bToMac64b(self, 
                        &nextAddr,
                        &temp_prefix,
                        &msg->l2_nextORpreviousHop
                    );
                } else {
                    hlen += 2;
                    switch(next_type){
                    case RH3_6LOTH_TYPE_0:
                        memcpy(&firstAddr.addr_128b[15],msg->payload+hlen,1);
                        hlen += 1;
                        break;
                    case RH3_6LOTH_TYPE_1:
                        memcpy(&firstAddr.addr_128b[14],msg->payload+hlen,2);
                        hlen += 2;
                        break;
                    case RH3_6LOTH_TYPE_2:
                        memcpy(&firstAddr.addr_128b[12],msg->payload+hlen,4);
                        hlen += 4;
                        break;
                    case RH3_6LOTH_TYPE_3:
                        memcpy(&firstAddr.addr_128b[8],msg->payload+hlen,8);
                        hlen += 8;
                        break;
                    }
                    next_size = temp_8b & RH3_6LOTH_SIZE_MASK;
 packetfunctions_tossHeader(self, msg,hlen);
                    if (next_size>0){
                        next_size -= 1;
 packetfunctions_reserveHeaderSize(self, msg,2);
                        msg->payload[0] = CRITICAL_6LORH | next_size;
                        msg->payload[1] = next_type;
                    }
                    // add first address
                    switch(type){
                    case RH3_6LOTH_TYPE_0:
 packetfunctions_reserveHeaderSize(self, msg,1);
                        msg->payload[0] = firstAddr.addr_128b[15];
                        break;
                    case RH3_6LOTH_TYPE_1:
 packetfunctions_reserveHeaderSize(self, msg,2);
                        memcpy(&msg->payload[0],&firstAddr.addr_128b[14],2);
                        break;
                    case RH3_6LOTH_TYPE_2:
 packetfunctions_reserveHeaderSize(self, msg,4);
                        memcpy(&msg->payload[0],&firstAddr.addr_128b[12],4);
                        break;
                    case RH3_6LOTH_TYPE_3:
 packetfunctions_reserveHeaderSize(self, msg,8);
                        memcpy(&msg->payload[0],&firstAddr.addr_128b[8],8);
                        break;
                    case RH3_6LOTH_TYPE_4:
 packetfunctions_reserveHeaderSize(self, msg,16);
                        memcpy(&msg->payload[0],&firstAddr.addr_128b[0],16);
                        break;
                    }
 packetfunctions_reserveHeaderSize(self, msg,2);
                    msg->payload[0] = CRITICAL_6LORH | 0;
                    msg->payload[1] = type;
 packetfunctions_ip128bToMac64b(self, 
                        &firstAddr,
                        &temp_prefix,
                        &msg->l2_nextORpreviousHop
                    );
                }
            } else {
                // there is no next RH3-6loRH, remove current one
 packetfunctions_tossHeader(self, msg,hlen);
 packetfunctions_ip128bToMac64b(self, 
                    &msg->l3_destinationAdd,
                    &temp_prefix,
                    &msg->l2_nextORpreviousHop
                );
            }
        }
    } else {
        // log error
 openserial_printError(self, 
            COMPONENT_IPHC,
            ERR_6LOWPAN_UNSUPPORTED,
            (errorparameter_t)16,
            (errorparameter_t)(temp_addr64.addr_64b[7])
        );
    }
    // copy RH3s before toss them
    if (
        ipv6_outer_header->src.type != ADDR_NONE &&
        ipv6_outer_header->hopByhop_option != NULL
    ){
        // check the length of RH3s
        RH3_length = ipv6_outer_header->hopByhop_option-msg->payload;
        memcpy(&RH3_copy[0],msg->payload,RH3_length);
 packetfunctions_tossHeader(self, msg,RH3_length);
        
        // retrieve hop-by-hop header (includes RPL option)
        rpi_length = iphc_retrieveIPv6HopByHopHeader(self, 
                          msg,
                          rpl_option
                     );
     
        // toss the headers
 packetfunctions_tossHeader(self, 
            msg,
            rpi_length
        );
      
        flags = rpl_option->flags;
        senderRank = rpl_option->senderRank;
        if ((flags & O_FLAG)!=O_FLAG){
            // wrong direction
            // log error
 openserial_printError(self, 
                COMPONENT_FORWARDING,
                ERR_WRONG_DIRECTION,
                (errorparameter_t)flags,
                (errorparameter_t)senderRank
            );
        }
        if (senderRank > neighbors_getMyDAGrank(self)){
            // loop detected
            // set flag
            rpl_option->flags |= R_FLAG;
            // log error
 openserial_printError(self, 
                COMPONENT_FORWARDING,
                ERR_LOOP_DETECTED,
                (errorparameter_t) senderRank,
                (errorparameter_t) neighbors_getMyDAGrank(self)
            );
        }
 forwarding_createRplOption(self, rpl_option, rpl_option->flags);
        // toss the IP in IP 6LoRH
 packetfunctions_tossHeader(self, msg, ipv6_outer_header->header_length);
    } else {
        RH3_length = 0;
    }
    
    // send to next lower layer
    return iphc_sendFromForwarding(self, 
        msg,
        ipv6_outer_header,
        ipv6_inner_header,
        rpl_option,
        &ipv6_outer_header->flow_label,
        &RH3_copy[0],
        RH3_length,
        PCKTFORWARD
    );
}
Exemplo n.º 4
0
/**
\brief Send a packet originating at this mote.

This function is called by an upper layer, and only concerns packets originated
at this mote.

\param[in,out] msg Packet to send.
*/
owerror_t forwarding_send(OpenMote* self, OpenQueueEntry_t* msg) {
    ipv6_header_iht      ipv6_outer_header;
    ipv6_header_iht      ipv6_inner_header;
    rpl_option_ht        rpl_option;
    open_addr_t*         myprefix;
    open_addr_t*         myadd64;
    uint32_t             flow_label = 0;

    open_addr_t          temp_dest_prefix;
    open_addr_t          temp_dest_mac64b;
    open_addr_t*         p_dest;
    open_addr_t*         p_src;  
    open_addr_t          temp_src_prefix;
    open_addr_t          temp_src_mac64b; 
    uint8_t              sam;
    uint8_t              m;
    uint8_t              dam;

    // take ownership over the packet
    msg->owner                = COMPONENT_FORWARDING;

    m   = IPHC_M_NO;

    // retrieve my prefix and EUI64
    myprefix                  = idmanager_getMyID(self, ADDR_PREFIX);
    myadd64                   = idmanager_getMyID(self, ADDR_64B);

    // set source address (me)
    msg->l3_sourceAdd.type=ADDR_128B;
    memcpy(&(msg->l3_sourceAdd.addr_128b[0]),myprefix->prefix,8);
    memcpy(&(msg->l3_sourceAdd.addr_128b[8]),myadd64->addr_64b,8);

    // initialize IPv6 header
    memset(&ipv6_outer_header,0,sizeof(ipv6_header_iht));
    memset(&ipv6_inner_header,0,sizeof(ipv6_header_iht));

    // Set hop limit to the default in-network value as this packet is being
    // sent from upper layer. This is done here as send_internal() is used by
    // forwarding of packets as well which carry a hlim. This value is required
    // to be set to a value as the following function can decrement it.
    ipv6_inner_header.hop_limit     = IPHC_DEFAULT_HOP_LIMIT;

    // create the RPL hop-by-hop option

 forwarding_createRplOption(self, 
      &rpl_option,      // rpl_option to fill in
      0x00              // flags
    );

 packetfunctions_ip128bToMac64b(self, &(msg->l3_destinationAdd),&temp_dest_prefix,&temp_dest_mac64b);
    //xv poipoi -- get the src prefix as well
 packetfunctions_ip128bToMac64b(self, &(msg->l3_sourceAdd),&temp_src_prefix,&temp_src_mac64b);
    //XV -poipoi we want to check if the source address prefix is the same as destination prefix
    if ( packetfunctions_sameAddress(self, &temp_dest_prefix,&temp_src_prefix)) {
         // same prefix use 64B address
         sam = IPHC_SAM_64B;
         dam = IPHC_DAM_64B;
         p_dest = &temp_dest_mac64b;      
         p_src  = &temp_src_mac64b; 
    } else {
        //not the same prefix. so the packet travels to another network
        //check if this is a source routing pkt. in case it is then the DAM is elided as it is in the SrcRouting header.
        if ( packetfunctions_isBroadcastMulticast(self, &(msg->l3_destinationAdd))==FALSE){
            sam = IPHC_SAM_128B;
            dam = IPHC_DAM_128B;
            p_dest = &(msg->l3_destinationAdd);
            p_src = &(msg->l3_sourceAdd);
            
            ipv6_outer_header.src.type = ADDR_128B;
            memcpy(&ipv6_outer_header.src,p_src,sizeof(open_addr_t));
            ipv6_outer_header.hop_limit = IPHC_DEFAULT_HOP_LIMIT;
        } else {
           // this is DIO, source address elided, multicast bit is set
            sam = IPHC_SAM_ELIDED;
            m   = IPHC_M_YES;
            dam = IPHC_DAM_ELIDED;
            p_dest = &(msg->l3_destinationAdd);
            p_src = &(msg->l3_sourceAdd);
        }
    }
    //IPHC inner header and NHC IPv6 header will be added at here
 iphc_prependIPv6Header(self, msg,
                IPHC_TF_ELIDED,
                flow_label, // value_flowlabel
                IPHC_NH_INLINE,
                msg->l4_protocol, 
                IPHC_HLIM_64,
                ipv6_outer_header.hop_limit,
                IPHC_CID_NO,
                IPHC_SAC_STATELESS,
                sam,
                m,
                IPHC_DAC_STATELESS,
                dam,
                p_dest,
                p_src,            
                PCKTSEND  
                );
    // both of them are compressed
    ipv6_outer_header.next_header_compressed = TRUE;

    return forwarding_send_internal_RoutingTable(self, 
        msg,
        &ipv6_outer_header,
        &ipv6_inner_header,
        &rpl_option,
        &flow_label,
        PCKTSEND
    );
}
Exemplo n.º 5
0
/**
\brief Indicates a packet was received.

\param[in,out] msg               The packet just sent.
\param[in]     ipv6_header       The information contained in the IPv6 header.
\param[in]     ipv6_hop_header   The hop-by-hop header present in the packet.
\param[in]     rpl_option        The hop-by-hop options present in the packet.
*/
void forwarding_receive(OpenMote* self, 
      OpenQueueEntry_t*      msg,
      ipv6_header_iht*       ipv6_outer_header,
      ipv6_header_iht*       ipv6_inner_header,
      rpl_option_ht*         rpl_option
    ) {
    uint8_t flags;
    uint16_t senderRank;
   
    // take ownership
    msg->owner                     = COMPONENT_FORWARDING;
   
    // determine L4 protocol
    // get information from ipv6_header
    msg->l4_protocol            = ipv6_inner_header->next_header;
    msg->l4_protocol_compressed = ipv6_inner_header->next_header_compressed;
   
    // populate packets metadata with L3 information
    memcpy(&(msg->l3_destinationAdd),&ipv6_inner_header->dest, sizeof(open_addr_t));
    memcpy(&(msg->l3_sourceAdd),     &ipv6_inner_header->src,  sizeof(open_addr_t));
   
    if (
        (
 idmanager_isMyAddress(self, &(msg->l3_destinationAdd))
            ||
 packetfunctions_isBroadcastMulticast(self, &(msg->l3_destinationAdd))
        )
        &&
        ipv6_outer_header->next_header!=IANA_IPv6ROUTE
    ) {
        if (ipv6_outer_header->src.type != ADDR_NONE){
 packetfunctions_tossHeader(self, msg,ipv6_outer_header->header_length);
        }
        // this packet is for me, no source routing header // toss iphc inner header
 packetfunctions_tossHeader(self, msg,ipv6_inner_header->header_length);
        // indicate received packet to upper layer
        switch(msg->l4_protocol) {
        case IANA_TCP:
 opentcp_receive(self, msg);
            break;
        case IANA_UDP:
 openudp_receive(self, msg);
            break;
        case IANA_ICMPv6:
 icmpv6_receive(self, msg);
            break;
        default:
            // log error
 openserial_printError(self, 
                COMPONENT_FORWARDING,ERR_WRONG_TRAN_PROTOCOL,
                (errorparameter_t)msg->l4_protocol,
                (errorparameter_t)1
            );
            
            // free packet
 openqueue_freePacketBuffer(self, msg);
        }
    } else {
        // this packet is not for me: relay
      
        // change the creator of the packet
        msg->creator = COMPONENT_FORWARDING;
      
        if (ipv6_outer_header->next_header!=IANA_IPv6ROUTE) {
            flags = rpl_option->flags;
            senderRank = rpl_option->senderRank;
            if ((flags & O_FLAG)!=0){
                // wrong direction
                // log error
 openserial_printError(self, 
                    COMPONENT_FORWARDING,
                    ERR_WRONG_DIRECTION,
                    (errorparameter_t)flags,
                    (errorparameter_t)senderRank
                );
            }
            if (senderRank < neighbors_getMyDAGrank(self)){
                // loop detected
                // set flag
                rpl_option->flags |= R_FLAG;
                // log error
 openserial_printError(self, 
                    COMPONENT_FORWARDING,
                    ERR_LOOP_DETECTED,
                    (errorparameter_t) senderRank,
                    (errorparameter_t) neighbors_getMyDAGrank(self)
                );
            }
 forwarding_createRplOption(self, rpl_option, rpl_option->flags);
            // resend as if from upper layer
            if (
 forwarding_send_internal_RoutingTable(self, 
                    msg,
                    ipv6_outer_header,
                    ipv6_inner_header,
                    rpl_option,
                    &(ipv6_outer_header->flow_label),
                    PCKTFORWARD 
                )==E_FAIL
            ) {
 openqueue_freePacketBuffer(self, msg);
            }
        } else {
            // source routing header present
            if (
 forwarding_send_internal_SourceRouting(self, 
                    msg,
                    ipv6_outer_header,
                    ipv6_inner_header,
                    rpl_option
                )==E_FAIL
            ) {
                // log error
 openserial_printError(self, 
                    COMPONENT_FORWARDING,
                    ERR_INVALID_FWDMODE,
                    (errorparameter_t)0,
                    (errorparameter_t)0
                );
            }
        }
    }
}