1.1 --- a/src/node/packet-socket.cc	Wed Jun 04 10:47:34 2008 -0700
     1.2 +++ b/src/node/packet-socket.cc	Wed Jun 04 10:59:30 2008 -0700
     1.3 @@ -27,6 +27,8 @@
     1.4  #include "ns3/uinteger.h"
     1.5  #include "ns3/trace-source-accessor.h"
     1.6  
     1.7 +#include <algorithm>
     1.8 +
     1.9  NS_LOG_COMPONENT_DEFINE ("PacketSocket");
    1.10  
    1.11  namespace ns3 {
    1.12 @@ -240,11 +242,35 @@
    1.13    return SendTo (p, m_destAddr);
    1.14  }
    1.15  
    1.16 -// XXX must limit it to interface MTU
    1.17 +uint32_t
    1.18 +PacketSocket::GetMinMtu (PacketSocketAddress ad) const
    1.19 +{
    1.20 +  if (ad.IsSingleDevice ())
    1.21 +    {
    1.22 +      Ptr<NetDevice> device = m_node->GetDevice (ad.GetSingleDevice ());
    1.23 +      return device->GetMtu ();
    1.24 +    }
    1.25 +  else
    1.26 +    {
    1.27 +      uint32_t minMtu = 0xffff;
    1.28 +      for (uint32_t i = 0; i < m_node->GetNDevices (); i++)
    1.29 +        {
    1.30 +          Ptr<NetDevice> device = m_node->GetDevice (i);
    1.31 +          minMtu = std::min (minMtu, (uint32_t)device->GetMtu ());
    1.32 +        }
    1.33 +      return minMtu;
    1.34 +    }
    1.35 +}
    1.36 +
    1.37  uint32_t 
    1.38  PacketSocket::GetTxAvailable (void) const
    1.39  {
    1.40 -  // Use 65536 for now
    1.41 +  if (m_state == STATE_CONNECTED)
    1.42 +    {
    1.43 +      PacketSocketAddress ad = PacketSocketAddress::ConvertFrom (m_destAddr);      
    1.44 +      return GetMinMtu (ad);
    1.45 +    }
    1.46 +  // If we are not connected, we return a 'safe' value by default.
    1.47    return 0xffff;
    1.48  }
    1.49  
    1.50 @@ -271,12 +297,12 @@
    1.51        m_errno = ERROR_AFNOSUPPORT;
    1.52        return -1;
    1.53      }
    1.54 -  if (p->GetSize () > GetTxAvailable ())
    1.55 +  ad = PacketSocketAddress::ConvertFrom (address);
    1.56 +  if (p->GetSize () > GetMinMtu (ad))
    1.57      {
    1.58        m_errno = ERROR_MSGSIZE;
    1.59        return -1;
    1.60      }
    1.61 -  ad = PacketSocketAddress::ConvertFrom (address);
    1.62    
    1.63    bool error = false;
    1.64    Address dest = ad.GetPhysicalAddress ();

     2.1 --- a/src/node/packet-socket.h	Wed Jun 04 10:47:34 2008 -0700
     2.2 +++ b/src/node/packet-socket.h	Wed Jun 04 10:59:30 2008 -0700
     2.3 @@ -105,6 +105,7 @@
     2.4    void ForwardUp (Ptr<NetDevice> device, Ptr<Packet> packet, 
     2.5                    uint16_t protocol, const Address &from);
     2.6    int DoBind (const PacketSocketAddress &address);
     2.7 +  uint32_t GetMinMtu (PacketSocketAddress ad) const;
     2.8    virtual void DoDispose (void);
     2.9  
    2.10    enum State {