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/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/**
* Copyright (c) 2014, Regents of the University of California,
* Arizona Board of Regents,
* Colorado State University,
* University Pierre & Marie Curie, Sorbonne University,
* Washington University in St. Louis,
* Beijing Institute of Technology,
* The University of Memphis
*
* This file is part of NFD (Named Data Networking Forwarding Daemon).
* See AUTHORS.md for complete list of NFD authors and contributors.
*
* NFD is free software: you can redistribute it and/or modify it under the terms
* of the GNU General Public License as published by the Free Software Foundation,
* either version 3 of the License, or (at your option) any later version.
*
* NFD 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
* NFD, e.g., in COPYING.md file. If not, see <http://www.gnu.org/licenses/>.
*/
#include "rib.hpp"
#include "core/logger.hpp"
NFD_LOG_INIT("Rib");
namespace nfd {
namespace rib {
static inline bool
sortRoutes(const Route& lhs, const Route& rhs)
{
return lhs.faceId < rhs.faceId;
}
static inline bool
isChildInheritFlagSet(uint64_t flags)
{
return flags & ndn::nfd::ROUTE_FLAG_CHILD_INHERIT;
}
static inline bool
isCaptureFlagSet(uint64_t flags)
{
return flags & ndn::nfd::ROUTE_FLAG_CAPTURE;
}
static inline bool
isAnyFlagSet(uint64_t flags)
{
return isChildInheritFlagSet(flags) || isCaptureFlagSet(flags);
}
static inline bool
areBothFlagsSet(uint64_t flags)
{
return isChildInheritFlagSet(flags) && isCaptureFlagSet(flags);
}
Rib::Rib()
: m_nItems(0)
{
}
Rib::const_iterator
Rib::find(const Name& prefix) const
{
return m_rib.find(prefix);
}
Route*
Rib::find(const Name& prefix, const Route& route) const
{
RibTable::const_iterator ribIt = m_rib.find(prefix);
// Name prefix exists
if (ribIt != m_rib.end())
{
shared_ptr<RibEntry> entry = ribIt->second;
RibEntry::iterator routeIt = entry->findRoute(route);
if (routeIt != entry->end())
{
return &((*routeIt));
}
}
return nullptr;
}
void
Rib::insert(const Name& prefix, const Route& route)
{
RibTable::iterator ribIt = m_rib.find(prefix);
// Name prefix exists
if (ribIt != m_rib.end())
{
shared_ptr<RibEntry> entry(ribIt->second);
RibEntry::iterator routeIt = entry->findRoute(route);
if (routeIt == entry->end())
{
// Will the new route change the namespace's capture flag?
bool captureWasTurnedOn = (entry->hasCapture() == false && isCaptureFlagSet(route.flags));
// New route
entry->insertRoute(route);
m_nItems++;
// Register with face lookup table
m_faceMap[route.faceId].push_back(entry);
createFibUpdatesForNewRoute(*entry, route, captureWasTurnedOn);
}
else // Route exists, update fields
{
// First cancel old scheduled event, if any, then set the EventId to new one
if (static_cast<bool>(routeIt->getExpirationEvent()))
{
NFD_LOG_TRACE("Cancelling expiration event for " << entry->getName() << " "
<< *routeIt);
scheduler::cancel(routeIt->getExpirationEvent());
}
// No checks are required here as the iterator needs to be updated in all cases.
routeIt->setExpirationEvent(route.getExpirationEvent());
// Save flags for update processing
uint64_t previousFlags = routeIt->flags;
// If the route's cost didn't change and child inherit is not set,
// no need to traverse subtree.
uint64_t previousCost = routeIt->cost;
routeIt->flags = route.flags;
routeIt->cost = route.cost;
routeIt->expires = route.expires;
createFibUpdatesForUpdatedRoute(*entry, route, previousFlags, previousCost);
}
}
else // New name prefix
{
shared_ptr<RibEntry> entry(make_shared<RibEntry>(RibEntry()));
m_rib[prefix] = entry;
m_nItems++;
entry->setName(prefix);
entry->insertRoute(route);
// Find prefix's parent
shared_ptr<RibEntry> parent = findParent(prefix);
// Add self to parent's children
if (static_cast<bool>(parent))
{
parent->addChild(entry);
}
RibEntryList children = findDescendants(prefix);
for (std::list<shared_ptr<RibEntry> >::iterator child = children.begin();
child != children.end(); ++child)
{
if ((*child)->getParent() == parent)
{
// Remove child from parent and inherit parent's child
if (static_cast<bool>(parent))
{
parent->removeChild((*child));
}
entry->addChild((*child));
}
}
// Register with face lookup table
m_faceMap[route.faceId].push_back(entry);
createFibUpdatesForNewRibEntry(*entry, route);
// do something after inserting an entry
afterInsertEntry(prefix);
}
}
void
Rib::erase(const Name& prefix, const Route& route)
{
RibTable::iterator ribIt = m_rib.find(prefix);
// Name prefix exists
if (ribIt != m_rib.end())
{
shared_ptr<RibEntry> entry(ribIt->second);
const bool hadCapture = entry->hasCapture();
// Need to copy route to do FIB updates with correct cost and flags since nfdc does not
// pass flags or cost
RibEntry::iterator routeIt = entry->findRoute(route);
if (routeIt != entry->end())
{
Route routeToErase = *routeIt;
routeToErase.flags = routeIt->flags;
routeToErase.cost = routeIt->cost;
entry->eraseRoute(routeIt);
m_nItems--;
const bool captureWasTurnedOff = (hadCapture && !entry->hasCapture());
createFibUpdatesForErasedRoute(*entry, routeToErase, captureWasTurnedOff);
// If this RibEntry no longer has this faceId, unregister from face lookup table
if (!entry->hasFaceId(route.faceId))
{
m_faceMap[route.faceId].remove(entry);
}
else
{
// The RibEntry still has the face ID; need to update FIB
// with lowest cost for the same route instead of removing the route from the FIB
shared_ptr<Route> lowCostRoute = entry->getRouteWithLowestCostByFaceId(route.faceId);
BOOST_ASSERT(static_cast<bool>(lowCostRoute));
createFibUpdatesForNewRoute(*entry, *lowCostRoute, false);
}
// If a RibEntry's route list is empty, remove it from the tree
if (entry->getRoutes().size() == 0)
{
eraseEntry(ribIt);
}
}
}
}
void
Rib::erase(const uint64_t faceId)
{
FaceLookupTable::iterator lookupIt = m_faceMap.find(faceId);
// No RIB entries have this face
if (lookupIt == m_faceMap.end())
{
return;
}
RibEntryList& ribEntries = lookupIt->second;
// For each RIB entry that has faceId, remove the face from the entry
for (shared_ptr<RibEntry>& entry : ribEntries)
{
const bool hadCapture = entry->hasCapture();
// Find the routes in the entry
for (RibEntry::iterator routeIt = entry->begin(); routeIt != entry->end(); ++routeIt)
{
if (routeIt->faceId == faceId)
{
Route copy = *routeIt;
routeIt = entry->eraseRoute(routeIt);
m_nItems--;
const bool captureWasTurnedOff = (hadCapture && !entry->hasCapture());
createFibUpdatesForErasedRoute(*entry, copy, captureWasTurnedOff);
}
}
// If a RibEntry's route list is empty, remove it from the tree
if (entry->getRoutes().size() == 0)
{
eraseEntry(m_rib.find(entry->getName()));
}
}
// Face no longer exists, remove from face lookup table
m_faceMap.erase(lookupIt);
}
shared_ptr<RibEntry>
Rib::findParent(const Name& prefix) const
{
for (int i = prefix.size() - 1; i >= 0; i--)
{
RibTable::const_iterator it = m_rib.find(prefix.getPrefix(i));
if (it != m_rib.end())
{
return (it->second);
}
}
return shared_ptr<RibEntry>();
}
std::list<shared_ptr<RibEntry> >
Rib::findDescendants(const Name& prefix) const
{
std::list<shared_ptr<RibEntry> > children;
RibTable::const_iterator it = m_rib.find(prefix);
if (it != m_rib.end())
{
++it;
for (; it != m_rib.end(); ++it)
{
if (prefix.isPrefixOf(it->first))
{
children.push_back((it->second));
}
else
{
break;
}
}
}
return children;
}
Rib::RibTable::iterator
Rib::eraseEntry(RibTable::iterator it)
{
// Entry does not exist
if (it == m_rib.end())
{
return m_rib.end();
}
shared_ptr<RibEntry> entry(it->second);
// Remove inherited routes from namespace
createFibUpdatesForErasedRibEntry(*entry);
shared_ptr<RibEntry> parent = entry->getParent();
// Remove self from parent's children
if (static_cast<bool>(parent))
{
parent->removeChild(entry);
}
std::list<shared_ptr<RibEntry> > children = entry->getChildren();
for (RibEntryList::iterator child = children.begin(); child != children.end(); ++child)
{
// Remove children from self
entry->removeChild(*child);
// Update parent's children
if (static_cast<bool>(parent))
{
parent->addChild(*child);
}
}
// Must save and advance iterator to return a valid iterator
RibTable::iterator nextIt = it;
nextIt++;
m_rib.erase(it);
// do something after erasing an entry.
afterEraseEntry(entry->getName());
return nextIt;
}
bool
compareFibUpdates(const shared_ptr<const FibUpdate> lhs, const shared_ptr<const FibUpdate> rhs)
{
return ((lhs->name == rhs->name) &&
(lhs->faceId == rhs->faceId));
}
void
Rib::insertFibUpdate(shared_ptr<FibUpdate> update)
{
// If an update with the same name and Face ID already exists, replace it
FibUpdateList::iterator it = std::find_if(m_fibUpdateList.begin(), m_fibUpdateList.end(),
bind(&compareFibUpdates, _1, update));
if (it != m_fibUpdateList.end())
{
// Get rid of the const to alter the action, prevents copying or removal and
// insertion
FibUpdate& entry = const_cast<FibUpdate&>(*(*it));
entry.action = update->action;
entry.cost = update->cost;
}
else
{
m_fibUpdateList.push_back(update);
}
}
void
Rib::createFibUpdatesForNewRibEntry(RibEntry& entry, const Route& route)
{
// Create FIB update for new entry
insertFibUpdate(FibUpdate::createAddUpdate(entry.getName(), route.faceId, route.cost));
// No flags are set
if (!isAnyFlagSet(route.flags))
{
// Add ancestor routes to self
addInheritedRoutesToEntry(entry, getAncestorRoutes(entry));
}
else if (areBothFlagsSet(route.flags))
{
// Add route to children
RouteSet routesToAdd;
routesToAdd.insert(route);
// Remove routes blocked by capture and add self to children
modifyChildrensInheritedRoutes(entry, routesToAdd, getAncestorRoutes(entry));
}
else if (isChildInheritFlagSet(route.flags))
{
RouteSet ancestorRoutes = getAncestorRoutes(entry);
// Add ancestor routes to self
addInheritedRoutesToEntry(entry, ancestorRoutes);
// If there is an ancestor route with the same Face ID as the new route, replace it
// with the new route
RouteSet::iterator it = ancestorRoutes.find(route);
// There is a route that needs to be overwritten, erase and then replace
if (it != ancestorRoutes.end())
{
ancestorRoutes.erase(it);
}
// Add new route to ancestor list so it can be added to children
ancestorRoutes.insert(route);
// Add ancestor routes to children
modifyChildrensInheritedRoutes(entry, ancestorRoutes, RouteSet());
}
else if (isCaptureFlagSet(route.flags))
{
// Remove routes blocked by capture
modifyChildrensInheritedRoutes(entry, RouteSet(), getAncestorRoutes(entry));
}
}
void
Rib::createFibUpdatesForNewRoute(RibEntry& entry, const Route& route, bool captureWasTurnedOn)
{
// Only update if the new route has a lower cost than a previously installed route
shared_ptr<Route> prevRoute = entry.getRouteWithLowestCostAndChildInheritByFaceId(route.faceId);
RouteSet routesToAdd;
if (isChildInheritFlagSet(route.flags))
{
// Add to children if this new route doesn't override a previous lower cost, or
// add to children if this new route is lower cost than a previous route.
// Less than equal, since entry may find this route
if (prevRoute == nullptr || route.cost <= prevRoute->cost)
{
// Add self to children
routesToAdd.insert(route);
}
}
RouteSet routesToRemove;
if (captureWasTurnedOn)
{
// Capture flag on
routesToRemove = getAncestorRoutes(entry);
// Remove ancestor routes from self
removeInheritedRoutesFromEntry(entry, routesToRemove);
}
modifyChildrensInheritedRoutes(entry, routesToAdd, routesToRemove);
// If another route with same faceId and lower cost, don't update.
// Must be done last so that add updates replace removal updates
// Create FIB update for new entry
if (route.cost <= entry.getRouteWithLowestCostByFaceId(route.faceId)->cost)
{
insertFibUpdate(FibUpdate::createAddUpdate(entry.getName(), route.faceId, route.cost));
}
}
void
Rib::createFibUpdatesForUpdatedRoute(RibEntry& entry, const Route& route,
const uint64_t previousFlags, const uint64_t previousCost)
{
const bool costDidChange = (route.cost != previousCost);
// Look for the installed route with the lowest cost and child inherit set
shared_ptr<Route> prevRoute = entry.getRouteWithLowestCostAndChildInheritByFaceId(route.faceId);
// No flags changed and cost didn't change, no change in FIB
if (route.flags == previousFlags && !costDidChange)
{
return;
}
// Cost changed so create update for the entry itself
if (costDidChange)
{
// Create update if this route's cost is lower than other routes
if (route.cost <= entry.getRouteWithLowestCostByFaceId(route.faceId)->cost)
{
// Create FIB update for the updated entry
insertFibUpdate(FibUpdate::createAddUpdate(entry.getName(), route.faceId, route.cost));
}
else if (previousCost < entry.getRouteWithLowestCostByFaceId(route.faceId)->cost)
{
// Create update if this route used to be the lowest cost route but is no longer
// the lowest cost route.
insertFibUpdate(FibUpdate::createAddUpdate(entry.getName(), prevRoute->faceId,
prevRoute->cost));
}
// If another route with same faceId and lower cost and ChildInherit exists,
// don't update children.
if (prevRoute == nullptr || route.cost <= prevRoute->cost)
{
// If no flags changed but child inheritance is set, need to update children
// with new cost
if ((route.flags == previousFlags) && isChildInheritFlagSet(route.flags))
{
// Add self to children
RouteSet routesToAdd;
routesToAdd.insert(route);
modifyChildrensInheritedRoutes(entry, routesToAdd, RouteSet());
return;
}
}
}
// Child inherit was turned on
if (!isChildInheritFlagSet(previousFlags) && isChildInheritFlagSet(route.flags))
{
// If another route with same faceId and lower cost and ChildInherit exists,
// don't update children.
if (prevRoute == nullptr || route.cost <= prevRoute->cost)
{
// Add self to children
RouteSet routesToAdd;
routesToAdd.insert(route);
modifyChildrensInheritedRoutes(entry, routesToAdd, RouteSet());
}
} // Child inherit was turned off
else if (isChildInheritFlagSet(previousFlags) && !isChildInheritFlagSet(route.flags))
{
// Remove self from children
RouteSet routesToRemove;
routesToRemove.insert(route);
RouteSet routesToAdd;
// If another route with same faceId and ChildInherit exists, update children with this route.
if (prevRoute != nullptr)
{
routesToAdd.insert(*prevRoute);
}
else
{
// Look for an ancestor that was blocked previously
const RouteSet ancestorRoutes = getAncestorRoutes(entry);
RouteSet::iterator it = ancestorRoutes.find(route);
// If an ancestor is found, add it to children
if (it != ancestorRoutes.end())
{
routesToAdd.insert(*it);
}
}
modifyChildrensInheritedRoutes(entry, routesToAdd, routesToRemove);
}
// Capture was turned on
if (!isCaptureFlagSet(previousFlags) && isCaptureFlagSet(route.flags))
{
RouteSet ancestorRoutes = getAncestorRoutes(entry);
// Remove ancestor routes from self
removeInheritedRoutesFromEntry(entry, ancestorRoutes);
// Remove ancestor routes from children
modifyChildrensInheritedRoutes(entry, RouteSet(), ancestorRoutes);
} // Capture was turned off
else if (isCaptureFlagSet(previousFlags) && !isCaptureFlagSet(route.flags))
{
RouteSet ancestorRoutes = getAncestorRoutes(entry);
// Add ancestor routes to self
addInheritedRoutesToEntry(entry, ancestorRoutes);
// Add ancestor routes to children
modifyChildrensInheritedRoutes(entry, ancestorRoutes, RouteSet());
}
}
void
Rib::createFibUpdatesForErasedRoute(RibEntry& entry, const Route& route,
const bool captureWasTurnedOff)
{
insertFibUpdate(FibUpdate::createRemoveUpdate(entry.getName(), route.faceId));
if (areBothFlagsSet(route.flags))
{
// Remove self from children
RouteSet routesToRemove;
routesToRemove.insert(route);
// If capture is turned off for the route, need to add ancestors
// to self and children
RouteSet routesToAdd;
if (captureWasTurnedOff)
{
// Look for ancestors that were blocked previously
routesToAdd = getAncestorRoutes(entry);
// Add ancestor routes to self
addInheritedRoutesToEntry(entry, routesToAdd);
}
modifyChildrensInheritedRoutes(entry, routesToAdd, routesToRemove);
}
else if (isChildInheritFlagSet(route.flags))
{
// If not blocked by capture, add inherited routes to children
RouteSet routesToAdd;
if (!entry.hasCapture())
{
routesToAdd = getAncestorRoutes(entry);
}
RouteSet routesToRemove;
routesToRemove.insert(route);
// Add ancestor routes to children
modifyChildrensInheritedRoutes(entry, routesToAdd, routesToRemove);
}
else if (isCaptureFlagSet(route.flags))
{
// If capture is turned off for the route, need to add ancestors
// to self and children
RouteSet routesToAdd;
if (captureWasTurnedOff)
{
// Look for an ancestors that were blocked previously
routesToAdd = getAncestorRoutes(entry);
// Add ancestor routes to self
addInheritedRoutesToEntry(entry, routesToAdd);
}
modifyChildrensInheritedRoutes(entry, routesToAdd, RouteSet());
}
// Need to check if the removed route was blocking an inherited route
RouteSet ancestorRoutes = getAncestorRoutes(entry);
if (!entry.hasCapture())
{
// If there is an ancestor route with the same Face ID as the erased route, add that route
// to the current entry
RouteSet::iterator it = ancestorRoutes.find(route);
if (it != ancestorRoutes.end())
{
entry.addInheritedRoute(*it);
insertFibUpdate(FibUpdate::createAddUpdate(entry.getName(), it->faceId, it->cost));
}
}
}
void
Rib::createFibUpdatesForErasedRibEntry(RibEntry& entry)
{
for (RibEntry::RouteList::iterator it = entry.getInheritedRoutes().begin();
it != entry.getInheritedRoutes().end(); ++it)
{
insertFibUpdate(FibUpdate::createRemoveUpdate(entry.getName(), it->faceId));
}
}
Rib::RouteSet
Rib::getAncestorRoutes(const RibEntry& entry) const
{
RouteSet ancestorRoutes(&sortRoutes);
shared_ptr<RibEntry> parent = entry.getParent();
while (static_cast<bool>(parent))
{
for (RibEntry::iterator it = parent->getRoutes().begin();
it != parent->getRoutes().end(); ++it)
{
if (isChildInheritFlagSet(it->flags))
{
ancestorRoutes.insert(*it);
}
}
if (parent->hasCapture())
{
break;
}
parent = parent->getParent();
}
return ancestorRoutes;
}
void
Rib::addInheritedRoutesToEntry(RibEntry& entry, const Rib::RouteSet& routesToAdd)
{
for (RouteSet::const_iterator it = routesToAdd.begin(); it != routesToAdd.end(); ++it)
{
// Don't add an ancestor route if the namespace has a route with that Face ID
if (!entry.hasFaceId(it->faceId))
{
entry.addInheritedRoute(*it);
insertFibUpdate(FibUpdate::createAddUpdate(entry.getName(), it->faceId, it->cost));
}
}
}
void
Rib::removeInheritedRoutesFromEntry(RibEntry& entry, const Rib::RouteSet& routesToRemove)
{
for (RouteSet::const_iterator it = routesToRemove.begin(); it != routesToRemove.end(); ++it)
{
// Only remove if the route has been inherited
if (entry.hasInheritedRoute(*it))
{
entry.removeInheritedRoute(*it);
insertFibUpdate(FibUpdate::createRemoveUpdate(entry.getName(), it->faceId));
}
}
}
void
Rib::modifyChildrensInheritedRoutes(RibEntry& entry, const Rib::RouteSet& routesToAdd,
const Rib::RouteSet& routesToRemove)
{
RibEntryList children = entry.getChildren();
for (RibEntryList::iterator child = children.begin(); child != children.end(); ++child)
{
traverseSubTree(*(*child), routesToAdd, routesToRemove);
}
}
void
Rib::traverseSubTree(RibEntry& entry, Rib::RouteSet routesToAdd, Rib::RouteSet routesToRemove)
{
// If a route on the namespace has the capture flag set, ignore self and children
if (entry.hasCapture())
{
return;
}
// Remove inherited routes from current namespace
for (Rib::RouteSet::const_iterator removeIt = routesToRemove.begin();
removeIt != routesToRemove.end(); )
{
// If a route on the namespace has the same face and child inheritance set, ignore this route
if (entry.hasChildInheritOnFaceId(removeIt->faceId))
{
routesToRemove.erase(removeIt++);
continue;
}
// Only remove route if it removes an existing inherited route
if (entry.hasInheritedRoute(*removeIt))
{
entry.removeInheritedRoute(*removeIt);
insertFibUpdate(FibUpdate::createRemoveUpdate(entry.getName(), removeIt->faceId));
}
++removeIt;
}
// Add inherited routes to current namespace
for (Rib::RouteSet::const_iterator addIt = routesToAdd.begin(); addIt != routesToAdd.end(); )
{
// If a route on the namespace has the same face and child inherit set, ignore this route
if (entry.hasChildInheritOnFaceId(addIt->faceId))
{
routesToAdd.erase(addIt++);
continue;
}
// Only add route if it does not override an existing route
if (!entry.hasFaceId(addIt->faceId))
{
RibEntry::RouteList::iterator routeIt = entry.findInheritedRoute(*addIt);
// If the entry already has the inherited route, just update the route
if (routeIt != entry.getInheritedRoutes().end())
{
routeIt->cost = addIt->cost;
}
else // Otherwise, this is a newly inherited route
{
entry.addInheritedRoute(*addIt);
}
insertFibUpdate(FibUpdate::createAddUpdate(entry.getName(), addIt->faceId, addIt->cost));
}
++addIt;
}
Rib::RibEntryList children = entry.getChildren();
// Apply route operations to current namespace's children
for (Rib::RibEntryList::iterator child = children.begin(); child != children.end(); ++child)
{
traverseSubTree(*(*child), routesToAdd, routesToRemove);
}
}
std::ostream&
operator<<(std::ostream& os, const Rib& rib)
{
for (Rib::RibTable::const_iterator it = rib.begin(); it != rib.end(); ++it)
{
os << *(it->second) << "\n";
}
return os;
}
} // namespace rib
} // namespace nfd