gkserver.h

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/*
 * gkserver.h
 *
 * H225 Registration Admission and Security protocol handler
 *
 * Open H323 Library
 *
 * Copyright (c) 1998-2001 Equivalence Pty. Ltd.
 *
 * The contents of this file are subject to the Mozilla Public License
 * Version 1.0 (the "License"); you may not use this file except in
 * compliance with the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS"
 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
 * the License for the specific language governing rights and limitations
 * under the License.
 *
 * The Original Code is Open H323 Library.
 *
 * The Initial Developer of the Original Code is Equivalence Pty. Ltd.
 *
 * This code was based on original code from OpenGate of Egoboo Ltd. thanks
 * to Ashley Unitt for his efforts.
 *
 * Contributor(s): ______________________________________.
 *
 * $Revision: 24178 $
 * $Author: rjongbloed $
 * $Date: 2010-04-06 10:10:56 +1000 (Tue, 06 Apr 2010) $
 */

#ifndef OPAL_H323_GKSERVER_H
#define OPAL_H323_GKSERVER_H

#ifdef P_USE_PRAGMA
#pragma interface
#endif

#include <opal/buildopts.h>

#if OPAL_H323

#include <ptlib/safecoll.h>
#include <opal/guid.h>
#include <h323/h225ras.h>
#include <h323/transaddr.h>
#include <h323/h235auth.h>
#include <h323/h323pdu.h>
#include <h323/h323trans.h>


class PASN_Sequence;
class PASN_Choice;

class H225_AliasAddress;
class H225_EndpointIdentifier;
class H225_GatekeeperIdentifier;
class H225_ArrayOf_TransportAddress;
class H225_GatekeeperIdentifier;
class H225_EndpointIdentifier;
class H225_InfoRequestResponse_perCallInfo_subtype;
class H225_RasUsageInformation;

class H323RegisteredEndPoint;
class H323GatekeeperListener;
class H323GatekeeperServer;
class H323RasPDU;

#if OPAL_H501
class H323PeerElement;
#endif

class H323GatekeeperRequest : public H323Transaction
{
    PCLASSINFO(H323GatekeeperRequest, H323Transaction);
  public:
    H323GatekeeperRequest(
      H323GatekeeperListener & rasChannel,
      const H323RasPDU & pdu
    );

    virtual H323TransactionPDU * CreateRIP(
      unsigned sequenceNumber,
      unsigned delay
    ) const;

    virtual PBoolean WritePDU(
      H323TransactionPDU & pdu
    );
    PBoolean CheckCryptoTokens();
    PBoolean CheckGatekeeperIdentifier();
    PBoolean GetRegisteredEndPoint();

    virtual PString GetGatekeeperIdentifier() const = 0;
    virtual unsigned GetGatekeeperRejectTag() const = 0;
    virtual PString GetEndpointIdentifier() const = 0;
    virtual unsigned GetRegisteredEndPointRejectTag() const = 0;
    virtual unsigned GetSecurityRejectTag() const = 0;

    H323GatekeeperListener & GetRasChannel() const { return rasChannel; }

    PSafePtr<H323RegisteredEndPoint> endpoint;

  protected:
    H323GatekeeperListener & rasChannel;
};


class H323GatekeeperGRQ : public H323GatekeeperRequest
{
    PCLASSINFO(H323GatekeeperGRQ, H323GatekeeperRequest);
  public:
    H323GatekeeperGRQ(
      H323GatekeeperListener & listener,
      const H323RasPDU & pdu
    );

#if PTRACING
    virtual const char * GetName() const;
#endif
    virtual PString GetGatekeeperIdentifier() const;
    virtual unsigned GetGatekeeperRejectTag() const;
    virtual PString GetEndpointIdentifier() const;
    virtual unsigned GetRegisteredEndPointRejectTag() const;
    virtual H235Authenticator::ValidationResult ValidatePDU() const;
    virtual unsigned GetSecurityRejectTag() const;
    virtual void SetRejectReason(
      unsigned reasonCode
    );

    H225_GatekeeperRequest & grq;
    H225_GatekeeperConfirm & gcf;
    H225_GatekeeperReject  & grj;

  protected:
    virtual Response OnHandlePDU();
};


class H323GatekeeperRRQ : public H323GatekeeperRequest
{
    PCLASSINFO(H323GatekeeperRRQ, H323GatekeeperRequest);
  public:
    H323GatekeeperRRQ(
      H323GatekeeperListener & listener,
      const H323RasPDU & pdu
    );

#if PTRACING
    virtual const char * GetName() const;
#endif
    virtual PString GetGatekeeperIdentifier() const;
    virtual unsigned GetGatekeeperRejectTag() const;
    virtual PString GetEndpointIdentifier() const;
    virtual unsigned GetRegisteredEndPointRejectTag() const;
    virtual H235Authenticator::ValidationResult ValidatePDU() const;
    virtual unsigned GetSecurityRejectTag() const;
    virtual void SetRejectReason(
      unsigned reasonCode
    );

    H225_RegistrationRequest & rrq;
    H225_RegistrationConfirm & rcf;
    H225_RegistrationReject  & rrj;

  protected:
    virtual Response OnHandlePDU();
};


class H323GatekeeperURQ : public H323GatekeeperRequest
{
    PCLASSINFO(H323GatekeeperURQ, H323GatekeeperRequest);
  public:
    H323GatekeeperURQ(
      H323GatekeeperListener & listener,
      const H323RasPDU & pdu
    );

#if PTRACING
    virtual const char * GetName() const;
#endif
    virtual PString GetGatekeeperIdentifier() const;
    virtual unsigned GetGatekeeperRejectTag() const;
    virtual PString GetEndpointIdentifier() const;
    virtual unsigned GetRegisteredEndPointRejectTag() const;
    virtual H235Authenticator::ValidationResult ValidatePDU() const;
    virtual unsigned GetSecurityRejectTag() const;
    virtual void SetRejectReason(
      unsigned reasonCode
    );

    H225_UnregistrationRequest & urq;
    H225_UnregistrationConfirm & ucf;
    H225_UnregistrationReject  & urj;

  protected:
    virtual Response OnHandlePDU();
};


class H323GatekeeperARQ : public H323GatekeeperRequest
{
    PCLASSINFO(H323GatekeeperARQ, H323GatekeeperRequest);
  public:
    H323GatekeeperARQ(
      H323GatekeeperListener & listener,
      const H323RasPDU & pdu
    );

#if PTRACING
    virtual const char * GetName() const;
#endif
    virtual PString GetGatekeeperIdentifier() const;
    virtual unsigned GetGatekeeperRejectTag() const;
    virtual PString GetEndpointIdentifier() const;
    virtual unsigned GetRegisteredEndPointRejectTag() const;
    virtual H235Authenticator::ValidationResult ValidatePDU() const;
    virtual unsigned GetSecurityRejectTag() const;
    virtual void SetRejectReason(
      unsigned reasonCode
    );

    H225_AdmissionRequest & arq;
    H225_AdmissionConfirm & acf;
    H225_AdmissionReject  & arj;

    PString alternateSecurityID;

  protected:
    virtual Response OnHandlePDU();
};


class H323GatekeeperDRQ : public H323GatekeeperRequest
{
    PCLASSINFO(H323GatekeeperDRQ, H323GatekeeperRequest);
  public:
    H323GatekeeperDRQ(
      H323GatekeeperListener & listener,
      const H323RasPDU & pdu
    );

#if PTRACING
    virtual const char * GetName() const;
#endif
    virtual PString GetGatekeeperIdentifier() const;
    virtual unsigned GetGatekeeperRejectTag() const;
    virtual PString GetEndpointIdentifier() const;
    virtual unsigned GetRegisteredEndPointRejectTag() const;
    virtual H235Authenticator::ValidationResult ValidatePDU() const;
    virtual unsigned GetSecurityRejectTag() const;
    virtual void SetRejectReason(
      unsigned reasonCode
    );

    H225_DisengageRequest & drq;
    H225_DisengageConfirm & dcf;
    H225_DisengageReject  & drj;

  protected:
    virtual Response OnHandlePDU();
};


class H323GatekeeperBRQ : public H323GatekeeperRequest
{
    PCLASSINFO(H323GatekeeperBRQ, H323GatekeeperRequest);
  public:
    H323GatekeeperBRQ(
      H323GatekeeperListener & listener,
      const H323RasPDU & pdu
    );

#if PTRACING
    virtual const char * GetName() const;
#endif
    virtual PString GetGatekeeperIdentifier() const;
    virtual unsigned GetGatekeeperRejectTag() const;
    virtual PString GetEndpointIdentifier() const;
    virtual unsigned GetRegisteredEndPointRejectTag() const;
    virtual H235Authenticator::ValidationResult ValidatePDU() const;
    virtual unsigned GetSecurityRejectTag() const;
    virtual void SetRejectReason(
      unsigned reasonCode
    );

    H225_BandwidthRequest & brq;
    H225_BandwidthConfirm & bcf;
    H225_BandwidthReject  & brj;

  protected:
    virtual Response OnHandlePDU();
};


class H323GatekeeperLRQ : public H323GatekeeperRequest
{
    PCLASSINFO(H323GatekeeperLRQ, H323GatekeeperRequest);
  public:
    H323GatekeeperLRQ(
      H323GatekeeperListener & listener,
      const H323RasPDU & pdu
    );

#if PTRACING
    virtual const char * GetName() const;
#endif
    virtual PString GetGatekeeperIdentifier() const;
    virtual unsigned GetGatekeeperRejectTag() const;
    virtual PString GetEndpointIdentifier() const;
    virtual unsigned GetRegisteredEndPointRejectTag() const;
    virtual H235Authenticator::ValidationResult ValidatePDU() const;
    virtual unsigned GetSecurityRejectTag() const;
    virtual void SetRejectReason(
      unsigned reasonCode
    );

    H225_LocationRequest & lrq;
    H225_LocationConfirm & lcf;
    H225_LocationReject  & lrj;

  protected:
    virtual Response OnHandlePDU();
};


class H323GatekeeperIRR : public H323GatekeeperRequest
{
    PCLASSINFO(H323GatekeeperIRR, H323GatekeeperRequest);
  public:
    H323GatekeeperIRR(
      H323GatekeeperListener & listener,
      const H323RasPDU & pdu
    );

#if PTRACING
    virtual const char * GetName() const;
#endif
    virtual PString GetGatekeeperIdentifier() const;
    virtual unsigned GetGatekeeperRejectTag() const;
    virtual PString GetEndpointIdentifier() const;
    virtual unsigned GetRegisteredEndPointRejectTag() const;
    virtual H235Authenticator::ValidationResult ValidatePDU() const;
    virtual unsigned GetSecurityRejectTag() const;
    virtual void SetRejectReason(
      unsigned reasonCode
    );

    H225_InfoRequestResponse & irr;
    H225_InfoRequestAck      & iack;
    H225_InfoRequestNak      & inak;

  protected:
    virtual Response OnHandlePDU();
};


class H323GatekeeperCall : public PSafeObject
{
    PCLASSINFO(H323GatekeeperCall, PSafeObject);
  public:
    enum Direction {
      AnsweringCall,
      OriginatingCall,
      UnknownDirection
    };

    H323GatekeeperCall(
      H323GatekeeperServer & server,               
      const OpalGloballyUniqueID & callIdentifier, 
      Direction direction                          
    );

    ~H323GatekeeperCall();

    Comparison Compare(
      const PObject & obj  
    ) const;

    void PrintOn(
      ostream & strm    
    ) const;

    virtual H323GatekeeperRequest::Response OnAdmission(
      H323GatekeeperARQ & request
    );

    virtual PBoolean Disengage(
      int reason = -1   
    );

    virtual H323GatekeeperRequest::Response OnDisengage(
      H323GatekeeperDRQ & request
    );

    virtual H323GatekeeperRequest::Response OnBandwidth(
      H323GatekeeperBRQ & request
    );

    virtual H323GatekeeperRequest::Response OnInfoResponse(
      H323GatekeeperIRR & request,
      H225_InfoRequestResponse_perCallInfo_subtype & call
    );

    virtual void OnAlerting();

    virtual void OnConnected();

    virtual PBoolean OnHeartbeat();

    virtual PString GetCallCreditAmount() const;

    virtual PBoolean GetCallCreditMode() const;

    virtual unsigned GetDurationLimit() const;

    virtual PBoolean SendCallCreditServiceControl();

    PBoolean AddCallCreditServiceControl(
      H225_ArrayOf_ServiceControlSession & serviceControl
    ) const;

    virtual PBoolean SendServiceControlSession(
      const H323ServiceControlSession & session
    );

    virtual PBoolean TranslateAliasAddress(
      const H225_AliasAddress & alias,
      H225_ArrayOf_AliasAddress & aliases,
      H323TransportAddress & address,
      PBoolean & isGkRouted
    );


    H323GatekeeperServer & GetGatekeeper() const { return gatekeeper; }
    H323RegisteredEndPoint & GetEndPoint() const { return *PAssertNULL(endpoint); }
    PBoolean IsAnsweringCall() const { return direction == AnsweringCall; }
    unsigned GetCallReference() const { return callReference; }
    const OpalGloballyUniqueID & GetCallIdentifier() const { return callIdentifier; }
    const OpalGloballyUniqueID & GetConferenceIdentifier() const { return conferenceIdentifier; }
    const PString & GetSourceNumber() const { return srcNumber; }
    const PStringArray & GetSourceAliases() const { return srcAliases; }
    const H323TransportAddress & GetSourceHost() const { return srcHost; }
    PString GetSourceAddress() const;
    const PString & GetDestinationNumber() const { return dstNumber; }
    const PStringArray & GetDestinationAliases() const { return dstAliases; }
    const H323TransportAddress & GetDestinationHost() const { return dstHost; }
    PString GetDestinationAddress() const;
    unsigned GetBandwidthUsed() const { return bandwidthUsed; }
    PBoolean SetBandwidthUsed(unsigned bandwidth);
    const PTime & GetLastInfoResponseTime() const { return lastInfoResponse; }
    const PTime & GetCallStartTime() const { return callStartTime; }
    const PTime & GetAlertingTime() const { return alertingTime; }
    const PTime & GetConnectedTime() const { return connectedTime; }
    const PTime & GetCallEndTime() const { return callEndTime; }
    H323Connection::CallEndReason GetCallEndReason() const { return callEndReason; }

  protected:
    void SetUsageInfo(const H225_RasUsageInformation & usage);

    H323GatekeeperServer   & gatekeeper;
    H323RegisteredEndPoint * endpoint;
    H323GatekeeperListener * rasChannel;

    Direction            direction;
    unsigned             callReference;
    OpalGloballyUniqueID callIdentifier;
    OpalGloballyUniqueID conferenceIdentifier;
    PString              srcNumber;
    PStringArray         srcAliases;
    H323TransportAddress srcHost;
    PString              dstNumber;
    PStringArray         dstAliases;
    H323TransportAddress dstHost;
    unsigned             bandwidthUsed;
    unsigned             infoResponseRate;
    PTime                lastInfoResponse;

    PBoolean                          drqReceived;
    PTime                         callStartTime;
    PTime                         alertingTime;
    PTime                         connectedTime;
    PTime                         callEndTime;
    H323Connection::CallEndReason callEndReason;
};


class H323RegisteredEndPoint : public PSafeObject
{
    PCLASSINFO(H323RegisteredEndPoint, PSafeObject);
  public:
    H323RegisteredEndPoint(
      H323GatekeeperServer & server, 
      const PString & id             
    );

    Comparison Compare(
      const PObject & obj  
    ) const;

    void PrintOn(
      ostream & strm    
    ) const;

    virtual void AddCall(
      H323GatekeeperCall * call
    );

    virtual PBoolean RemoveCall(
      H323GatekeeperCall * call
    );

    PINDEX GetCallCount() const { return activeCalls.GetSize(); }

    H323GatekeeperCall & GetCall(
      PINDEX idx
    ) { return activeCalls[idx]; }

    virtual H323GatekeeperRequest::Response OnRegistration(
      H323GatekeeperRRQ & request
    );

    virtual H323GatekeeperRequest::Response OnFullRegistration(
      H323GatekeeperRRQ & request
    );

    virtual H323GatekeeperRequest::Response OnSecureRegistration(
      H323GatekeeperRRQ & request
    );

    virtual H323GatekeeperRequest::Response OnUnregistration(
      H323GatekeeperURQ & request
    );

    virtual PBoolean Unregister(
      int reason = -1   
    );

    virtual H323GatekeeperRequest::Response OnInfoResponse(
      H323GatekeeperIRR & request
    );

    virtual PBoolean OnTimeToLive();

    virtual PString GetCallCreditAmount() const;

    virtual PBoolean GetCallCreditMode() const;

    virtual PBoolean SendServiceControlSession(
      const H323ServiceControlSession & session
    );

    virtual PBoolean AddServiceControlSession(
      const H323ServiceControlSession & session,
      H225_ArrayOf_ServiceControlSession & serviceControl
    );

    virtual PBoolean SetPassword(
      const PString & password,
      const PString & username = PString::Empty()
    );

    const PString & GetIdentifier() const { return identifier; }

    const OpalGloballyUniqueID & GetDescriptorID() const { return descriptorID; }

    H323GatekeeperServer & GetGatekeeper() const { return gatekeeper; }

    const H323TransportAddressArray & GetRASAddresses() const { return rasAddresses; }

    PINDEX GetRASAddressCount() const { return rasAddresses.GetSize(); }

    H323TransportAddress GetRASAddress(
      PINDEX idx
    ) const { return rasAddresses[idx]; }

    const H323TransportAddressArray & GetSignalAddresses() const { return signalAddresses; }

    PINDEX GetSignalAddressCount() const { return signalAddresses.GetSize(); }

    H323TransportAddress GetSignalAddress(
      PINDEX idx
    ) const { return signalAddresses[idx]; }

    const PStringArray & GetAliases() const { return aliases; }

    PBoolean ContainsAlias(
      const PString & alias
      ) { return aliases.GetStringsIndex(alias) != P_MAX_INDEX; }

    PINDEX GetAliasCount() const { return aliases.GetSize(); }

    PString GetAlias(
      PINDEX idx
    ) const { if (idx < aliases.GetSize()) return aliases[idx]; return PString::Empty(); }

    void RemoveAlias(
      const PString & alias
    );

    virtual const H235Authenticators & GetAuthenticators() const { return authenticators; }

    PINDEX GetPrefixCount() const { return voicePrefixes.GetSize(); }

    PString GetPrefix(
      PINDEX idx
    ) const { return voicePrefixes[idx]; }

    PCaselessString GetApplicationInfo() const { return productInfo.AsString(); }

    const OpalProductInfo & GetProductInfo() const { return productInfo; }

    unsigned GetProtocolVersion() const { return protocolVersion; }

    PBoolean IsBehindNAT() const { return isBehindNAT; }

    PBoolean CanDisplayAmountString() const { return canDisplayAmountString; }

    PBoolean CanEnforceDurationLimit() const { return canEnforceDurationLimit; }

    PBoolean CanReceiveRIP() const;

    PBoolean GetH225Version() const { return h225Version; }

      virtual PBoolean OnSendDescriptorForEndpoint(
        H225_ArrayOf_AliasAddress & aliases,          
        H225_EndpointType & terminalType,             
        H225_ArrayOf_AliasAddress & transportAddresses  
      );


  protected:
    H323GatekeeperServer    & gatekeeper;
    H323GatekeeperListener  * rasChannel;

    PString                   identifier;
    OpalGloballyUniqueID      descriptorID;
    H323TransportAddressArray rasAddresses;
    H323TransportAddressArray signalAddresses;
    PStringArray              aliases;
    PStringArray              voicePrefixes;
    OpalProductInfo           productInfo;
    unsigned                  protocolVersion;
    PBoolean                      isBehindNAT;
    PBoolean                      canDisplayAmountString;
    PBoolean                      canEnforceDurationLimit;
    unsigned                  h225Version;
    unsigned                  timeToLive;
    H235Authenticators        authenticators;

    PTime lastRegistration;
    PTime lastInfoResponse;

    PSortedList<H323GatekeeperCall> activeCalls;
    POrdinalDictionary<PString>     serviceControlSessions;
};


class H323GatekeeperListener : public H225_RAS
{
    PCLASSINFO(H323GatekeeperListener, H225_RAS);
  public:
    H323GatekeeperListener(
      H323EndPoint & endpoint,               
      H323GatekeeperServer & server,         
      const PString & gatekeeperIdentifier,  
      H323Transport * transport = NULL       
    );

    ~H323GatekeeperListener();

    PBoolean UnregistrationRequest(
      const H323RegisteredEndPoint & ep,
      unsigned reason
    );

    PBoolean DisengageRequest(
      const H323GatekeeperCall & call,
      unsigned reason
    );

    virtual PBoolean InfoRequest(
      H323RegisteredEndPoint & ep,
      H323GatekeeperCall * call = NULL
    );

    virtual PBoolean ServiceControlIndication(
      H323RegisteredEndPoint & ep,
      const H323ServiceControlSession & session,
      H323GatekeeperCall * call = NULL
    );

    virtual H323GatekeeperRequest::Response OnDiscovery(
      H323GatekeeperGRQ & request
    );

    virtual H323GatekeeperRequest::Response OnRegistration(
      H323GatekeeperRRQ & request
    );

    virtual H323GatekeeperRequest::Response OnUnregistration(
      H323GatekeeperURQ & request
    );

    virtual H323GatekeeperRequest::Response OnAdmission(
      H323GatekeeperARQ & request
    );

    virtual H323GatekeeperRequest::Response OnDisengage(
      H323GatekeeperDRQ & request
    );

    virtual H323GatekeeperRequest::Response OnBandwidth(
      H323GatekeeperBRQ & request
    );

    virtual H323GatekeeperRequest::Response OnLocation(
      H323GatekeeperLRQ & request
    );

    virtual H323GatekeeperRequest::Response OnInfoResponse(
      H323GatekeeperIRR & request
    );

    virtual PBoolean OnReceiveGatekeeperRequest(const H323RasPDU &, const H225_GatekeeperRequest &);
    virtual PBoolean OnReceiveRegistrationRequest(const H323RasPDU &, const H225_RegistrationRequest &);
    virtual PBoolean OnReceiveUnregistrationRequest(const H323RasPDU &, const H225_UnregistrationRequest &);
    virtual PBoolean OnReceiveUnregistrationConfirm(const H225_UnregistrationConfirm &);
    virtual PBoolean OnReceiveUnregistrationReject(const H225_UnregistrationReject &);
    virtual PBoolean OnReceiveAdmissionRequest(const H323RasPDU &, const H225_AdmissionRequest &);
    virtual PBoolean OnReceiveBandwidthRequest(const H323RasPDU &, const H225_BandwidthRequest &);
    virtual PBoolean OnReceiveBandwidthConfirm(const H225_BandwidthConfirm &);
    virtual PBoolean OnReceiveBandwidthReject(const H225_BandwidthReject &);
    virtual PBoolean OnReceiveDisengageRequest(const H323RasPDU &, const H225_DisengageRequest &);
    virtual PBoolean OnReceiveDisengageConfirm(const H225_DisengageConfirm &);
    virtual PBoolean OnReceiveDisengageReject(const H225_DisengageReject &);
    virtual PBoolean OnReceiveLocationRequest(const H323RasPDU &, const H225_LocationRequest &);
    virtual PBoolean OnReceiveInfoRequestResponse(const H323RasPDU &, const H225_InfoRequestResponse &);
    virtual PBoolean OnReceiveResourcesAvailableConfirm(const H225_ResourcesAvailableConfirm &);
    virtual PBoolean OnSendFeatureSet(unsigned, H225_FeatureSet & features) const;
    virtual void OnReceiveFeatureSet(unsigned, const H225_FeatureSet & features) const;

    H323GatekeeperServer & GetGatekeeper() const { return gatekeeper; }


  protected:
    H323GatekeeperServer & gatekeeper;
};


class H323GatekeeperServer : public H323TransactionServer
{
    PCLASSINFO(H323GatekeeperServer, H323TransactionServer);
  public:
    H323GatekeeperServer(
      H323EndPoint & endpoint
    );

    ~H323GatekeeperServer();

    WORD GetDefaultUdpPort() { return H225_RAS::DefaultRasUdpPort; }

    virtual H323Transactor * CreateListener(
      H323Transport * transport  
    );


    virtual H323GatekeeperRequest::Response OnDiscovery(
      H323GatekeeperGRQ & request
    );

    virtual H323GatekeeperRequest::Response OnRegistration(
      H323GatekeeperRRQ & request
    );

    virtual H323GatekeeperRequest::Response OnUnregistration(
      H323GatekeeperURQ & request
    );

    virtual H323GatekeeperRequest::Response OnInfoResponse(
      H323GatekeeperIRR & request
    );

    virtual void AddEndPoint(
      H323RegisteredEndPoint * ep
    );

    virtual PBoolean RemoveEndPoint(
      H323RegisteredEndPoint * ep
    );

    virtual H323RegisteredEndPoint * CreateRegisteredEndPoint(
      H323GatekeeperRRQ & request
    );

    virtual PString CreateEndPointIdentifier();

    virtual PSafePtr<H323RegisteredEndPoint> FindEndPointByIdentifier(
      const PString & identifier,
      PSafetyMode mode = PSafeReference
    );

    virtual PSafePtr<H323RegisteredEndPoint> FindEndPointBySignalAddresses(
      const H225_ArrayOf_TransportAddress & addresses,
      PSafetyMode mode = PSafeReference
    );

    virtual PSafePtr<H323RegisteredEndPoint> FindEndPointBySignalAddress(
      const H323TransportAddress & address,
      PSafetyMode mode = PSafeReference
    );

    virtual PSafePtr<H323RegisteredEndPoint> FindEndPointByAliasAddress(
      const H225_AliasAddress & alias,
      PSafetyMode mode = PSafeReadWrite
    );

    virtual PSafePtr<H323RegisteredEndPoint> FindEndPointByAliasString(
      const PString & alias,
      PSafetyMode mode = PSafeReference
    );

    virtual PSafePtr<H323RegisteredEndPoint> FindEndPointByPartialAlias(
      const PString & alias,
      PSafetyMode mode = PSafeReference
    );

    virtual PSafePtr<H323RegisteredEndPoint> FindEndPointByPrefixString(
      const PString & prefix,
      PSafetyMode mode = PSafeReference
    );

    PSafePtr<H323RegisteredEndPoint> GetFirstEndPoint(
      PSafetyMode mode = PSafeReference
    ) { return PSafePtr<H323RegisteredEndPoint>(byIdentifier, mode); }

    PSafePtr<H323RegisteredEndPoint> FindDestinationEndPoint(
      const OpalGloballyUniqueID & id, 
      H323GatekeeperCall::Direction direction
    );
    
    virtual H323GatekeeperRequest::Response OnAdmission(
      H323GatekeeperARQ & request
    );

    virtual H323GatekeeperRequest::Response OnDisengage(
      H323GatekeeperDRQ & request
    );

    virtual H323GatekeeperRequest::Response OnBandwidth(
      H323GatekeeperBRQ & request
    );

    virtual H323GatekeeperCall * CreateCall(
      const OpalGloballyUniqueID & callIdentifier,
      H323GatekeeperCall::Direction direction
    );

    virtual void AddCall(H323GatekeeperCall *) 
    { }

    virtual void RemoveCall(
      H323GatekeeperCall * call
    );

    virtual PSafePtr<H323GatekeeperCall> FindCall(
      const PString & description,
      PSafetyMode mode = PSafeReference
    );

    virtual PSafePtr<H323GatekeeperCall> FindCall(
      const OpalGloballyUniqueID & callIdentifier,
      PBoolean answeringCall,
      PSafetyMode mode = PSafeReference
    );

    virtual PSafePtr<H323GatekeeperCall> FindCall(
      const OpalGloballyUniqueID & callIdentifier,
      H323GatekeeperCall::Direction direction,
      PSafetyMode mode = PSafeReference
    );

    PSafePtr<H323GatekeeperCall> GetFirstCall(
      PSafetyMode mode = PSafeReference
    ) { return PSafePtr<H323GatekeeperCall>(activeCalls, mode); }

    virtual H323GatekeeperRequest::Response OnLocation(
      H323GatekeeperLRQ & request
    );

    virtual PBoolean TranslateAliasAddress(
      const H225_AliasAddress & alias,
      H225_ArrayOf_AliasAddress & aliases,
      H323TransportAddress & address,
      PBoolean & isGkRouted,
      H323GatekeeperCall * call
    );

    virtual PBoolean TranslateAliasAddressToSignalAddress(
      const H225_AliasAddress & alias,
      H323TransportAddress & address
    );

    virtual PBoolean CheckSignalAddressPolicy(
      const H323RegisteredEndPoint & ep,
      const H225_AdmissionRequest & arq,
      const H323TransportAddress & address
    );

    virtual PBoolean CheckAliasAddressPolicy(
      const H323RegisteredEndPoint & ep,
      const H225_AdmissionRequest & arq,
      const H225_AliasAddress & alias
    );

    virtual PBoolean CheckAliasStringPolicy(
      const H323RegisteredEndPoint & ep,
      const H225_AdmissionRequest & arq,
      const PString & alias
    );

    virtual unsigned AllocateBandwidth(
      unsigned newBandwidth,
      unsigned oldBandwidth = 0
    );

    virtual PBoolean GetAdmissionRequestAuthentication(
      H323GatekeeperARQ & info,           
      H235Authenticators & authenticators 
    );

    virtual PBoolean GetUsersPassword(
      const PString & alias,
      PString & password,
      H323RegisteredEndPoint & registeredEndpoint
    ) const;
    virtual PBoolean GetUsersPassword(
      const PString & alias,
      PString & password
    ) const;

#if OPAL_H501

    H323PeerElement * GetPeerElement() const { return peerElement; }

    void SetPeerElement(
      H323PeerElement * newPeerElement
    );

    void CreatePeerElement(
      const H323TransportAddress & h501Interface
    );

    PBoolean OpenPeerElement(
      const H323TransportAddress & remotePeer,
      PBoolean append = false,
      PBoolean keepTrying = true
    );
#endif

    const PString & GetGatekeeperIdentifier() const { return gatekeeperIdentifier; }

    void SetGatekeeperIdentifier(
      const PString & id,
      PBoolean adjustListeners = true
    );

    unsigned GetAvailableBandwidth() const { return totalBandwidth; }

    void SetAvailableBandwidth(unsigned bps100) { totalBandwidth = bps100; }

    unsigned GetUsedBandwidth() const { return usedBandwidth; }

    unsigned GetDefaultBandwidth() const { return defaultBandwidth; }

    unsigned GetTimeToLive() const { return defaultTimeToLive; }

    void SetTimeToLive(unsigned seconds) { defaultTimeToLive = seconds; }

    unsigned GetInfoResponseRate() const { return defaultInfoResponseRate; }

    void SetInfoResponseRate(unsigned seconds) { defaultInfoResponseRate = seconds; }

    PBoolean IsGatekeeperRouted() const { return isGatekeeperRouted; }

    PBoolean IsRequiredH235() const { return requireH235; }

    unsigned GetActiveRegistrations() const { return byIdentifier.GetSize(); }

    unsigned GetPeakRegistrations() const { return peakRegistrations; }

    unsigned GetTotalRegistrations() const { return totalRegistrations; }

    unsigned GetRejectedRegistrations() const { return rejectedRegistrations; }

    unsigned GetActiveCalls() const { return activeCalls.GetSize(); }

    unsigned GetPeakCalls() const { return peakCalls; }

    unsigned GetTotalCalls() const { return totalCalls; }

    unsigned GetRejectedCalls() const { return rejectedCalls; }

    // Remove an alias from the server database.
    void RemoveAlias(
      H323RegisteredEndPoint & ep,
      const PString & alias
    );

    // called when an endpoint needs to send a descriptor to the H.501 peer element
    virtual PBoolean OnSendDescriptorForEndpoint(
      H323RegisteredEndPoint & /*ep*/,                    
      H225_ArrayOf_AliasAddress & /*aliases*/,            
      H225_EndpointType & /*terminalType*/,               
      H225_ArrayOf_AliasAddress & /*transportAddresses*/  
    )
    { return true; } 

    virtual PBoolean AllowDuplicateAlias(const H225_ArrayOf_AliasAddress & /*aliases*/)
    { return canHaveDuplicateAlias; }

    virtual PBoolean OnSendFeatureSet(unsigned, H225_FeatureSet & features) const;
    virtual void OnReceiveFeatureSet(unsigned, const H225_FeatureSet & features) const;

  protected:

    PDECLARE_NOTIFIER(PThread, H323GatekeeperServer, MonitorMain);

    // Configuration & policy variables
    PString  gatekeeperIdentifier;
    unsigned totalBandwidth;
    unsigned usedBandwidth;
    unsigned defaultBandwidth;
    unsigned maximumBandwidth;
    unsigned defaultTimeToLive;
    unsigned defaultInfoResponseRate;
    PBoolean     overwriteOnSameSignalAddress;
    PBoolean     canHaveDuplicateAlias;
    PBoolean     canHaveDuplicatePrefix;
    PBoolean     canOnlyCallRegisteredEP;
    PBoolean     canOnlyAnswerRegisteredEP;
    PBoolean     answerCallPreGrantedARQ;
    PBoolean     makeCallPreGrantedARQ;
    PBoolean     isGatekeeperRouted;
    PBoolean     aliasCanBeHostName;
    PBoolean     requireH235;
    PBoolean     disengageOnHearbeatFail;

    PStringToString passwords;

    // Dynamic variables
    PMutex         mutex;
    time_t         identifierBase;
    unsigned       nextIdentifier;
    PThread      * monitorThread;
    PSyncPoint     monitorExit;

    PLIST(ListenerList, H323GatekeeperListener);
    ListenerList listeners;

#if OPAL_H501
    H323PeerElement * peerElement;
#endif

    PSafeDictionary<PString, H323RegisteredEndPoint> byIdentifier;

    class StringMap : public PString {
        PCLASSINFO(StringMap, PString);
      public:
        StringMap(const PString & from, const PString & id)
          : PString(from), identifier(id) { }
        PString identifier;
    };
    PSortedStringList byAddress;
    PSortedStringList byAlias;
    PSortedStringList byVoicePrefix;

    PSafeSortedList<H323GatekeeperCall> activeCalls;

    PINDEX peakRegistrations;
    PINDEX totalRegistrations;
    PINDEX rejectedRegistrations;
    PINDEX peakCalls;
    PINDEX totalCalls;
    PINDEX rejectedCalls;

  friend class H323GatekeeperRRQ;
  friend class H323GatekeeperARQ;
};


#endif // OPAL_H323

#endif // OPAL_H323_GKSERVER_H