lr-wpan: use multicast short addresses for multicast frames

src/lr-wpan/model/lr-wpan-mac.cc

@@ -597,8 +597,26 @@ LrWpanMac::PdDataIndication (uint32_t psduLength, Ptr<Packet> p, uint8_t lqi)
           if (acceptFrame
               && (receivedMacHdr.GetDstAddrMode () == 2))
             {
-              acceptFrame = receivedMacHdr.GetShortDstAddr () == m_shortAddress
-                || receivedMacHdr.GetShortDstAddr () == Mac16Address ("ff:ff");        // check for broadcast addrs
+              if (receivedMacHdr.GetShortDstAddr () == m_shortAddress)
+                {
+                  // unicast, for me
+                  acceptFrame = true;
+                }
+              else if (receivedMacHdr.GetShortDstAddr () == Mac16Address ("ff:ff"))
+                {
+                  // broadcast
+                  acceptFrame = true;
+                }
+              else
+                {
+                  // multicast
+                  uint8_t buf[2];
+                  receivedMacHdr.GetShortDstAddr ().CopyTo (buf);
+                  if (buf[0] & 0x80)
+                    {
+                      acceptFrame = true;
+                    }
+                }
             }
 
           if (acceptFrame

src/lr-wpan/model/lr-wpan-net-device.cc

@@ -284,19 +284,9 @@ LrWpanNetDevice::GetAddress (void) const
     {
       return m_mac->GetExtendedAddress ();
     }
-  uint8_t buf[6];
 
-  uint16_t panId = m_mac->GetPanId ();
-  buf[0] = panId >> 8;
-  // Make sure the U/L bit is set
-  buf[0] |= 0x02;
-  buf[1] = panId & 0xff;
-  buf[2] = 0;
-  buf[3] = 0;
-  m_mac->GetShortAddress ().CopyTo (buf+4);
+  Mac48Address pseudoAddress = BuildPseudoMacAddress (m_mac->GetPanId (), m_mac->GetShortAddress ());
 
-  Mac48Address pseudoAddress;
-  pseudoAddress.CopyFrom (buf);
   return pseudoAddress;
 }
 
@@ -343,18 +333,9 @@ Address
 LrWpanNetDevice::GetBroadcast (void) const
 {
   NS_LOG_FUNCTION (this);
-  uint8_t buf[6];
 
-  uint16_t panId = m_mac->GetPanId ();
-  buf[0] = panId >> 8;
-  buf[1] = panId & 0xff;
-  buf[2] = 0;
-  buf[3] = 0;
-  buf[4] = 0xff;
-  buf[5] = 0xff;
+  Mac48Address pseudoAddress = BuildPseudoMacAddress (m_mac->GetPanId (), Mac16Address::GetBroadcast ());
 
-  Mac48Address pseudoAddress;
-  pseudoAddress.CopyFrom (buf);
   return pseudoAddress;
 }
 
@@ -375,34 +356,11 @@ LrWpanNetDevice::GetMulticast (Ipv4Address multicastGroup) const
 Address
 LrWpanNetDevice::GetMulticast (Ipv6Address addr) const
 {
-  NS_LOG_FUNCTION (this);
-  /* Implementation based on RFC 4944 Section 9.
-   * An IPv6 packet with a multicast destination address (DST),
-   * consisting of the sixteen octets DST[1] through DST[16], is
-   * transmitted to the following 802.15.4 16-bit multicast address:
-   *           0                   1
-   *           0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
-   *          +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-   *          |1 0 0|DST[15]* |   DST[16]     |
-   *          +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-   * Here, DST[15]* refers to the last 5 bits in octet DST[15], that is,
-   * bits 3-7 within DST[15].  The initial 3-bit pattern of "100" follows
-   * the 16-bit address format for multicast addresses (Section 12). */
+  NS_LOG_FUNCTION (this << addr);
 
-  // \todo re-add this once Lr-Wpan will be able to accept these multicast addresses
-  //  uint8_t buf[16];
-  //  uint8_t buf2[2];
-  //
-  //  addr.GetBytes(buf);
-  //
-  //  buf2[0] = 0x80 | (buf[14] & 0x1F);
-  //  buf2[1] = buf[15];
-  //
-  //  Mac16Address newaddr = Mac16Address();
-  //  newaddr.CopyFrom(buf2);
-  //  return newaddr;
+  Mac48Address pseudoAddress = BuildPseudoMacAddress (m_mac->GetPanId (), Mac16Address::GetMulticast (addr));
 
-  return GetBroadcast ();
+  return pseudoAddress;
 }
 
 bool
@@ -527,6 +485,27 @@ LrWpanNetDevice::SupportsSendFrom (void) const
   return false;
 }
 
+Mac48Address
+LrWpanNetDevice::BuildPseudoMacAddress (uint16_t panId, Mac16Address shortAddr) const
+{
+  NS_LOG_FUNCTION (this);
+
+  uint8_t buf[6];
+
+  buf[0] = panId >> 8;
+  // Make sure the U/L bit is set
+  buf[0] |= 0x02;
+  buf[1] = panId & 0xff;
+  buf[2] = 0;
+  buf[3] = 0;
+  shortAddr.CopyTo (buf+4);
+
+  Mac48Address pseudoAddress;
+  pseudoAddress.CopyFrom (buf);
+
+  return pseudoAddress;
+}
+
 int64_t
 LrWpanNetDevice::AssignStreams (int64_t stream)
 {

src/lr-wpan/model/lr-wpan-net-device.h

@@ -190,6 +190,16 @@ private:
    */
   void CompleteConfig (void);
 
+  /**
+   * Builds a Mac48Address from the PanId and Short Address
+   * The form is PanId : 0x0 : 0x0 : ShortAddress
+   *
+   * \param panId The PanID
+   * \param shortMac The Short MAC address
+   * \return a Pseudo-Mac48Adress
+   */
+  Mac48Address BuildPseudoMacAddress (uint16_t panId, Mac16Address shortAddr) const;
+
   /**
    * The MAC for this NetDevice.
    */