internet: (fixes nsnam#62) ICMP handle time exceed responses.

Author: TommyPec

AUTHORS

@@ -248,3 +248,4 @@ He Wu (mdzz@u.washington.edu)
 Yoshihiko Yazawa (yoshiyaz@gmail.com)
 Menglei Zhang (menglei@nyu.edu)
 Dizhi Zhou (dizhi.zhou@gmail.com)
+Alberto Gallegos Ramonet (ramonet@fc.ritsumei.ac.jp)

src/internet-apps/examples/wscript

@@ -5,4 +5,4 @@ def build(bld):
         return;
 
     obj = bld.create_ns3_program('dhcp-example', ['internet', 'internet-apps', 'csma', 'point-to-point', 'applications'])
-    obj.source = 'dhcp-example.cc'
+    obj.source = 'dhcp-example.cc'

src/internet/model/ipv4-l3-protocol.cc

@@ -1029,9 +1029,8 @@ Ipv4L3Protocol::IpForward (Ptr<Ipv4Route> rtentry, Ptr<const Packet> p, const Ip
   ipHeader.SetTtl (ipHeader.GetTtl () - 1);
   if (ipHeader.GetTtl () == 0)
     {
-      // Do not reply to ICMP or to multicast/broadcast IP address 
-      if (ipHeader.GetProtocol () != Icmpv4L4Protocol::PROT_NUMBER && 
-          ipHeader.GetDestination ().IsBroadcast () == false &&
+      // Do not reply to multicast/broadcast IP address
+      if (ipHeader.GetDestination ().IsBroadcast () == false &&
           ipHeader.GetDestination ().IsMulticast () == false)
         {
           Ptr<Icmpv4L4Protocol> icmp = GetIcmp ();