Files
unison/src/internet/model/arp-cache.cc
2015-03-29 11:14:34 +02:00

483 lines
12 KiB
C++

/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/*
* Copyright (c) 2006 INRIA
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation;
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Author: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>
*/
#include "ns3/assert.h"
#include "ns3/packet.h"
#include "ns3/simulator.h"
#include "ns3/uinteger.h"
#include "ns3/log.h"
#include "ns3/node.h"
#include "ns3/trace-source-accessor.h"
#include "ns3/names.h"
#include "arp-cache.h"
#include "arp-header.h"
#include "ipv4-interface.h"
namespace ns3 {
NS_LOG_COMPONENT_DEFINE ("ArpCache");
NS_OBJECT_ENSURE_REGISTERED (ArpCache);
TypeId
ArpCache::GetTypeId (void)
{
static TypeId tid = TypeId ("ns3::ArpCache")
.SetParent<Object> ()
.SetGroupName ("Internet")
.AddAttribute ("AliveTimeout",
"When this timeout expires, "
"the matching cache entry needs refreshing",
TimeValue (Seconds (120)),
MakeTimeAccessor (&ArpCache::m_aliveTimeout),
MakeTimeChecker ())
.AddAttribute ("DeadTimeout",
"When this timeout expires, "
"a new attempt to resolve the matching entry is made",
TimeValue (Seconds (100)),
MakeTimeAccessor (&ArpCache::m_deadTimeout),
MakeTimeChecker ())
.AddAttribute ("WaitReplyTimeout",
"When this timeout expires, "
"the cache entries will be scanned and "
"entries in WaitReply state will resend ArpRequest "
"unless MaxRetries has been exceeded, "
"in which case the entry is marked dead",
TimeValue (Seconds (1)),
MakeTimeAccessor (&ArpCache::m_waitReplyTimeout),
MakeTimeChecker ())
.AddAttribute ("MaxRetries",
"Number of retransmissions of ArpRequest "
"before marking dead",
UintegerValue (3),
MakeUintegerAccessor (&ArpCache::m_maxRetries),
MakeUintegerChecker<uint32_t> ())
.AddAttribute ("PendingQueueSize",
"The size of the queue for packets pending an arp reply.",
UintegerValue (3),
MakeUintegerAccessor (&ArpCache::m_pendingQueueSize),
MakeUintegerChecker<uint32_t> ())
.AddTraceSource ("Drop",
"Packet dropped due to ArpCache entry "
"in WaitReply expiring.",
MakeTraceSourceAccessor (&ArpCache::m_dropTrace),
"ns3::Packet::TracedCallback")
;
return tid;
}
ArpCache::ArpCache ()
: m_device (0),
m_interface (0)
{
NS_LOG_FUNCTION (this);
}
ArpCache::~ArpCache ()
{
NS_LOG_FUNCTION (this);
}
void
ArpCache::DoDispose (void)
{
NS_LOG_FUNCTION (this);
Flush ();
m_device = 0;
m_interface = 0;
if (!m_waitReplyTimer.IsRunning ())
{
Simulator::Remove (m_waitReplyTimer);
}
Object::DoDispose ();
}
void
ArpCache::SetDevice (Ptr<NetDevice> device, Ptr<Ipv4Interface> interface)
{
NS_LOG_FUNCTION (this << device << interface);
m_device = device;
m_interface = interface;
}
Ptr<NetDevice>
ArpCache::GetDevice (void) const
{
NS_LOG_FUNCTION (this);
return m_device;
}
Ptr<Ipv4Interface>
ArpCache::GetInterface (void) const
{
NS_LOG_FUNCTION (this);
return m_interface;
}
void
ArpCache::SetAliveTimeout (Time aliveTimeout)
{
NS_LOG_FUNCTION (this << aliveTimeout);
m_aliveTimeout = aliveTimeout;
}
void
ArpCache::SetDeadTimeout (Time deadTimeout)
{
NS_LOG_FUNCTION (this << deadTimeout);
m_deadTimeout = deadTimeout;
}
void
ArpCache::SetWaitReplyTimeout (Time waitReplyTimeout)
{
NS_LOG_FUNCTION (this << waitReplyTimeout);
m_waitReplyTimeout = waitReplyTimeout;
}
Time
ArpCache::GetAliveTimeout (void) const
{
NS_LOG_FUNCTION (this);
return m_aliveTimeout;
}
Time
ArpCache::GetDeadTimeout (void) const
{
NS_LOG_FUNCTION (this);
return m_deadTimeout;
}
Time
ArpCache::GetWaitReplyTimeout (void) const
{
NS_LOG_FUNCTION (this);
return m_waitReplyTimeout;
}
void
ArpCache::SetArpRequestCallback (Callback<void, Ptr<const ArpCache>,
Ipv4Address> arpRequestCallback)
{
NS_LOG_FUNCTION (this << &arpRequestCallback);
m_arpRequestCallback = arpRequestCallback;
}
void
ArpCache::StartWaitReplyTimer (void)
{
NS_LOG_FUNCTION (this);
if (!m_waitReplyTimer.IsRunning ())
{
NS_LOG_LOGIC ("Starting WaitReplyTimer at " << Simulator::Now () << " for " <<
m_waitReplyTimeout);
m_waitReplyTimer = Simulator::Schedule (m_waitReplyTimeout,
&ArpCache::HandleWaitReplyTimeout, this);
}
}
void
ArpCache::HandleWaitReplyTimeout (void)
{
NS_LOG_FUNCTION (this);
ArpCache::Entry* entry;
bool restartWaitReplyTimer = false;
for (CacheI i = m_arpCache.begin (); i != m_arpCache.end (); i++)
{
entry = (*i).second;
if (entry != 0 && entry->IsWaitReply ())
{
if (entry->GetRetries () < m_maxRetries)
{
NS_LOG_LOGIC ("node="<< m_device->GetNode ()->GetId () <<
", ArpWaitTimeout for " << entry->GetIpv4Address () <<
" expired -- retransmitting arp request since retries = " <<
entry->GetRetries ());
m_arpRequestCallback (this, entry->GetIpv4Address ());
restartWaitReplyTimer = true;
entry->IncrementRetries ();
}
else
{
NS_LOG_LOGIC ("node="<<m_device->GetNode ()->GetId () <<
", wait reply for " << entry->GetIpv4Address () <<
" expired -- drop since max retries exceeded: " <<
entry->GetRetries ());
entry->MarkDead ();
entry->ClearRetries ();
Ptr<Packet> pending = entry->DequeuePending ();
while (pending != 0)
{
m_dropTrace (pending);
pending = entry->DequeuePending ();
}
}
}
}
if (restartWaitReplyTimer)
{
NS_LOG_LOGIC ("Restarting WaitReplyTimer at " << Simulator::Now ().GetSeconds ());
m_waitReplyTimer = Simulator::Schedule (m_waitReplyTimeout,
&ArpCache::HandleWaitReplyTimeout, this);
}
}
void
ArpCache::Flush (void)
{
NS_LOG_FUNCTION (this);
for (CacheI i = m_arpCache.begin (); i != m_arpCache.end (); i++)
{
delete (*i).second;
}
m_arpCache.erase (m_arpCache.begin (), m_arpCache.end ());
if (m_waitReplyTimer.IsRunning ())
{
NS_LOG_LOGIC ("Stopping WaitReplyTimer at " << Simulator::Now ().GetSeconds () << " due to ArpCache flush");
m_waitReplyTimer.Cancel ();
}
}
void
ArpCache::PrintArpCache (Ptr<OutputStreamWrapper> stream)
{
NS_LOG_FUNCTION (this << stream);
std::ostream* os = stream->GetStream ();
for (CacheI i = m_arpCache.begin (); i != m_arpCache.end (); i++)
{
*os << i->first << " dev ";
std::string found = Names::FindName (m_device);
if (Names::FindName (m_device) != "")
{
*os << found;
}
else
{
*os << static_cast<int> (m_device->GetIfIndex ());
}
*os << " lladdr " << i->second->GetMacAddress ();
if (i->second->IsAlive ())
{
*os << " REACHABLE\n";
}
else if (i->second->IsWaitReply ())
{
*os << " DELAY\n";
}
else
{
*os << " STALE\n";
}
}
}
ArpCache::Entry *
ArpCache::Lookup (Ipv4Address to)
{
NS_LOG_FUNCTION (this << to);
if (m_arpCache.find (to) != m_arpCache.end ())
{
ArpCache::Entry *entry = m_arpCache[to];
return entry;
}
return 0;
}
ArpCache::Entry *
ArpCache::Add (Ipv4Address to)
{
NS_LOG_FUNCTION (this << to);
NS_ASSERT (m_arpCache.find (to) == m_arpCache.end ());
ArpCache::Entry *entry = new ArpCache::Entry (this);
m_arpCache[to] = entry;
entry->SetIpv4Address (to);
return entry;
}
ArpCache::Entry::Entry (ArpCache *arp)
: m_arp (arp),
m_state (ALIVE),
m_retries (0)
{
NS_LOG_FUNCTION (this << arp);
}
bool
ArpCache::Entry::IsDead (void)
{
NS_LOG_FUNCTION (this);
return (m_state == DEAD) ? true : false;
}
bool
ArpCache::Entry::IsAlive (void)
{
NS_LOG_FUNCTION (this);
return (m_state == ALIVE) ? true : false;
}
bool
ArpCache::Entry::IsWaitReply (void)
{
NS_LOG_FUNCTION (this);
return (m_state == WAIT_REPLY) ? true : false;
}
void
ArpCache::Entry::MarkDead (void)
{
NS_LOG_FUNCTION (this);
m_state = DEAD;
ClearRetries ();
UpdateSeen ();
}
void
ArpCache::Entry::MarkAlive (Address macAddress)
{
NS_LOG_FUNCTION (this << macAddress);
NS_ASSERT (m_state == WAIT_REPLY);
m_macAddress = macAddress;
m_state = ALIVE;
ClearRetries ();
UpdateSeen ();
}
bool
ArpCache::Entry::UpdateWaitReply (Ptr<Packet> waiting)
{
NS_LOG_FUNCTION (this << waiting);
NS_ASSERT (m_state == WAIT_REPLY);
/* We are already waiting for an answer so
* we dump the previously waiting packet and
* replace it with this one.
*/
if (m_pending.size () >= m_arp->m_pendingQueueSize)
{
return false;
}
m_pending.push_back (waiting);
return true;
}
void
ArpCache::Entry::MarkWaitReply (Ptr<Packet> waiting)
{
NS_LOG_FUNCTION (this << waiting);
NS_ASSERT (m_state == ALIVE || m_state == DEAD);
NS_ASSERT (m_pending.empty ());
m_state = WAIT_REPLY;
m_pending.push_back (waiting);
UpdateSeen ();
m_arp->StartWaitReplyTimer ();
}
Address
ArpCache::Entry::GetMacAddress (void) const
{
NS_LOG_FUNCTION (this);
return m_macAddress;
}
Ipv4Address
ArpCache::Entry::GetIpv4Address (void) const
{
NS_LOG_FUNCTION (this);
return m_ipv4Address;
}
void
ArpCache::Entry::SetIpv4Address (Ipv4Address destination)
{
NS_LOG_FUNCTION (this << destination);
m_ipv4Address = destination;
}
Time
ArpCache::Entry::GetTimeout (void) const
{
NS_LOG_FUNCTION (this);
switch (m_state) {
case ArpCache::Entry::WAIT_REPLY:
return m_arp->GetWaitReplyTimeout ();
case ArpCache::Entry::DEAD:
return m_arp->GetDeadTimeout ();
case ArpCache::Entry::ALIVE:
return m_arp->GetAliveTimeout ();
default:
NS_ASSERT (false);
return Seconds (0);
/* NOTREACHED */
}
}
bool
ArpCache::Entry::IsExpired (void) const
{
NS_LOG_FUNCTION (this);
Time timeout = GetTimeout ();
Time delta = Simulator::Now () - m_lastSeen;
NS_LOG_DEBUG ("delta=" << delta.GetSeconds () << "s");
if (delta > timeout)
{
return true;
}
return false;
}
Ptr<Packet>
ArpCache::Entry::DequeuePending (void)
{
NS_LOG_FUNCTION (this);
if (m_pending.empty ())
{
return 0;
}
else
{
Ptr<Packet> p = m_pending.front ();
m_pending.pop_front ();
return p;
}
}
void
ArpCache::Entry::UpdateSeen (void)
{
NS_LOG_FUNCTION (this);
m_lastSeen = Simulator::Now ();
}
uint32_t
ArpCache::Entry::GetRetries (void) const
{
NS_LOG_FUNCTION (this);
return m_retries;
}
void
ArpCache::Entry::IncrementRetries (void)
{
NS_LOG_FUNCTION (this);
m_retries++;
UpdateSeen ();
}
void
ArpCache::Entry::ClearRetries (void)
{
NS_LOG_FUNCTION (this);
m_retries = 0;
}
} // namespace ns3