// -*- c-basic-offset: 4; tab-width: 8; indent-tabs-mode: t -*- // vim:set sts=4 ts=8: // Copyright (c) 2001-2005 International Computer Science Institute // // Permission is hereby granted, free of charge, to any person obtaining a // copy of this software and associated documentation files (the "Software") // to deal in the Software without restriction, subject to the conditions // listed in the XORP LICENSE file. These conditions include: you must // preserve this copyright notice, and you cannot mention the copyright // holders in advertising related to the Software without their permission. // The Software is provided WITHOUT ANY WARRANTY, EXPRESS OR IMPLIED. This // notice is a summary of the XORP LICENSE file; the license in that file is // legally binding. // $XORP: xorp/bgp/route_table_damping.hh,v 1.1 2005/12/06 06:26:36 atanu Exp $ #ifndef __BGP_ROUTE_TABLE_DAMPING_HH__ #define __BGP_ROUTE_TABLE_DAMPING_HH__ #include "libxorp/trie.hh" #include "route_table_base.hh" #include "damping.hh" #include "peer_handler.hh" /** * BGP Route Flap Damping RFC 2439 */ /** * An entry of this form exists for all networks. */ class Damp { public: Damp(uint32_t time, uint32_t merit) : _time(time), _merit(merit), _damped(false) {} uint32_t _time; // Last time the route was announced or withdrawn. uint32_t _merit; // Figure of merit. bool _damped; // True if this route is currently damped. }; /** * An entry of this form exists only if the route has been damped. */ template<class A> class DampRoute { public: DampRoute(const SubnetRoute<A>* route, uint32_t genid) : _routeref(route), _genid(genid) {} inline const SubnetRoute<A>* route() const {return _routeref.route();} inline uint32_t genid() const {return _genid;} inline XorpTimer& timer() { return _timer; } private: SubnetRouteConstRef<A> _routeref; uint32_t _genid; XorpTimer _timer; // If this route is damped time when it should // be released. }; /** * Manage the damping of routes. * * NOTE: If damping was enabled and is then disabled it is possible * that some routes may be damped. While damped routes exist the * damping code is entered, no more routes are damped but routes are * only released as the timers fire. */ template<class A> class DampingTable : public BGPRouteTable<A> { public: DampingTable(string tablename, Safi safi, BGPRouteTable<A>* parent, const PeerHandler *peer, Damping& damping); ~DampingTable(); int add_route(const InternalMessage<A> &rtmsg, BGPRouteTable<A> *caller); int replace_route(const InternalMessage<A> &old_rtmsg, const InternalMessage<A> &new_rtmsg, BGPRouteTable<A> *caller); int delete_route(const InternalMessage<A> &rtmsg, BGPRouteTable<A> *caller); int push(BGPRouteTable<A> *caller); int route_dump(const InternalMessage<A> &rtmsg, BGPRouteTable<A> *caller, const PeerHandler *dump_peer); const SubnetRoute<A> *lookup_route(const IPNet<A> &net, uint32_t& genid) const; void route_used(const SubnetRoute<A>* route, bool in_use); RouteTableType type() const {return DAMPING_TABLE;} string str() const; private: inline bool damping() const { if (_peer->ibgp()) return false; if (0 != _damp_count) return true; return _damping.get_damping(); } inline bool damping_global() const { return _damping.get_damping(); } /** * Update the figure of merit for this route. * * @return true if the route should be damped. */ bool update_figure_of_merit(Damp&damp, const InternalMessage<A> &rtmsg); /** * Is this route being damped. */ bool is_this_route_damped(const IPNet<A> &net) const; /** * Callback method called to release damped route. */ void undamp(IPNet<A> net); EventLoop& eventloop() const; private: const PeerHandler *_peer; Damping& _damping; Trie<A, Damp> _damp; RefTrie<A, DampRoute<A> > _damped; uint32_t _damp_count; // Number of damped routes. }; #endif // __BGP_ROUTE_TABLE_DAMPING_HH__