Bug 1814 - IPv6 Packets with length not multiple of 8 bytes are fragmented incorrectly.

RELEASE_NOTES

@@ -55,6 +55,7 @@ Bugs fixed
 - Bug 1802 - FlowMon header deserialization problem with IPv4 fragments
 - Bug 1807 - Multiple bugs in Ipv4L3Protocol::LocalDeliver
 - Bug 1810 - IP packets can be sent on NetDevices not respecting the minimum MTU requirements
+- Bug 1814 - IPv6 Packet with length not multiple of 8 bytes are fragmented incorrectly.
 
 Release 3.18.1
 ==============

src/internet/model/ipv6-extension-header.cc

@@ -334,6 +334,7 @@ Ipv6ExtensionFragmentHeader::Ipv6ExtensionFragmentHeader ()
   : m_offset (0),
     m_identification (0)
 {
+  SetLength (0);
 }
 
 Ipv6ExtensionFragmentHeader::~Ipv6ExtensionFragmentHeader ()
@@ -388,7 +389,7 @@ void Ipv6ExtensionFragmentHeader::Serialize (Buffer::Iterator start) const
   Buffer::Iterator i = start;
 
   i.WriteU8 (GetNextHeader ());
-  i.WriteU8 ((GetLength () >> 3) - 1);
+  i.WriteU8 (0);
   i.WriteHtonU16 (m_offset);
   i.WriteHtonU32 (m_identification);
 }
@@ -398,7 +399,8 @@ uint32_t Ipv6ExtensionFragmentHeader::Deserialize (Buffer::Iterator start)
   Buffer::Iterator i = start;
 
   SetNextHeader (i.ReadU8 ());
-  SetLength ((i.ReadU8 () + 1) << 3);
+  i.ReadU8();
+  SetLength (0);
   m_offset = i.ReadNtohU16 ();
   m_identification = i.ReadNtohU32 ();
 

src/internet/model/ipv6-extension.cc

@@ -510,6 +510,7 @@ void Ipv6ExtensionFragment::GetFragments (Ptr<Packet> packet, uint32_t maxFragme
         {
           moreFragment = true;
           currentFragmentablePartSize = maxFragmentablePartSize;
+          currentFragmentablePartSize -= currentFragmentablePartSize % 8;
         }
       else
         {
@@ -517,10 +518,8 @@ void Ipv6ExtensionFragment::GetFragments (Ptr<Packet> packet, uint32_t maxFragme
           currentFragmentablePartSize = p->GetSize () - offset;
         }
 
-      currentFragmentablePartSize -= currentFragmentablePartSize % 8;
 
       fragmentHeader.SetNextHeader (nextHeader);
-      fragmentHeader.SetLength (currentFragmentablePartSize);
       fragmentHeader.SetOffset (offset);
       fragmentHeader.SetMoreFragment (moreFragment);
       fragmentHeader.SetIdentification (identification);

src/internet/test/ipv6-fragmentation-test.cc

@@ -295,7 +295,7 @@ Ipv6FragmentationTest::DoRun (void)
   {
     clientDev = CreateObject<SimpleNetDevice> ();
     clientDev->SetAddress (Mac48Address::ConvertFrom (Mac48Address::Allocate ()));
-    clientDev->SetMtu (1000);
+    clientDev->SetMtu (1500);
     clientDev->SetReceiveErrorModel (clientDevErrorModel);
     clientDevErrorModel->Disable ();
     clientNode->AddDevice (clientDev);
@@ -315,7 +315,7 @@ Ipv6FragmentationTest::DoRun (void)
 
 
   // some small packets, some rather big ones
-  uint32_t packetSizes[5] = {1000, 2000, 5000, 10000, 65000};
+  uint32_t packetSizes[5] = {2000, 2500, 5000, 10000, 65000};
 
   // using the alphabet
   uint8_t fillData[78];