asner.h

开源代码的pwlib的1.10.0版本,使用openh323的1.18.0版本毕备

/*
 * asner.h
 *
 * Abstract Syntax Notation Encoding Rules classes
 *
 * Portable Windows Library
 *
 * Copyright (c) 1993-2002 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 Portable Windows Library.
 *
 * The Initial Developer of the Original Code is Equivalence Pty. Ltd.
 *
 * Contributor(s): ______________________________________.
 *
 * $Log: asner.h,v $
 * Revision 1.46  2005/11/25 01:01:13  csoutheren
 * Applied patch #1351168
 * PWlib various fixes
 *
 * Revision 1.45  2005/06/07 06:25:53  csoutheren
 * Applied patch 1199897 to increase speed of ASN parser debugging output
 * Thanks to Dmitriy <[e-mail]>
 *
 * Revision 1.44  2004/11/11 07:34:50  csoutheren
 * Added #include <ptlib.h>
 *
 * Revision 1.43  2004/04/18 04:33:35  rjongbloed
 * Changed all operators that return BOOL to return standard type bool. This is primarily
 *   for improved compatibility with std STL usage removing many warnings.
 *
 * Revision 1.42  2003/12/14 10:21:29  rjongbloed
 * Fixed bug in length incorrectlty decoded from ASN and (apparently) rare circumstances. Thanks [e-mail].
 * Cleaned up return values to be BOOL rather than int for some functions.
 *
 * Revision 1.41  2003/08/18 23:32:22  rjongbloed
 * Micro optimisation suggested by Chih-Wei Huang
 *
 * Revision 1.40  2003/08/01 16:00:51  csoutheren
 * Changed #if to #ifdef to (maybe) avoid compiler problems with gcc 2.95.2
 *
 * Revision 1.39  2003/08/01 02:12:34  csoutheren
 * Changed to allow easy isolation of PER, BER and XER encoding/decoding routines
 *
 * Revision 1.38  2003/04/22 23:39:09  craigs
 * Changed some functions from protected to public for MacOSX. Thanks to Hugo Santos
 *
 * Revision 1.37  2003/04/17 14:44:44  craigs
 * Removed MacOS specific defines to make some attributes public
 * Thanks to Hugo Santos and apologies to Roger Hardiman
 *
 * Revision 1.36  2003/02/26 01:57:44  robertj
 * Added XML encoding rules to ASN system, thanks Federico Pinna
 *
 * Revision 1.35  2003/02/01 13:25:52  robertj
 * Added function to add new elements directly to ASN array.
 *
 * Revision 1.34  2003/01/24 23:43:43  robertj
 * Fixed subtle problems with the use of MAX keyword for unsigned numbers,
 *   should beUINT_MAX not INT_MAX, thanks Stevie Gray for pointing it out.
 *
 * Revision 1.33  2002/11/26 23:29:18  robertj
 * Added missing const to DecodeSubType() function.
 *
 * Revision 1.32  2002/11/06 22:47:23  robertj
 * Fixed header comment (copyright etc)
 *
 * Revision 1.31  2002/10/31 05:50:49  robertj
 * Changed to use new UTF-8/UCS-2 conversion functions on PString.
 *
 * Revision 1.30  2002/10/10 14:37:40  rogerh
 * In two of the PASN classes make the protected members public. This
 * makes OpenH323 compile in Mac OS X 10.2.1
 *
 * Revision 1.29  2002/09/16 01:08:59  robertj
 * Added #define so can select if #pragma interface/implementation is used on
 *   platform basis (eg MacOS) rather than compiler, thanks Robert Monaghan.
 *
 * Revision 1.28  2002/05/29 01:22:35  robertj
 * Added ability to set object id from unsigned integer arrays.
 *
 * Revision 1.27  2002/05/21 04:23:40  robertj
 * Fixed problem with ASN encoding/decoding unsconstrained negative numbers,
 *
 * Revision 1.26  2002/05/14 06:59:31  robertj
 * Added more bullet proofing so a malformed PDU cannot cause teh decoder
 *   to try and allocate huge arrays and consume all CPU and memory on a
 *   system. A configurable limit of 100 is set for things like SEQUENCE OF.
 *
 * Revision 1.25  2001/12/13 09:13:28  robertj
 * Added function get get oid as a string.
 * Added functions to compare oid to PString.
 *
 * Revision 1.24  2001/09/14 01:59:59  robertj
 * Fixed problem with incorrectly initialised PASN_Choice sub-object.
 *
 * Revision 1.23  2001/08/06 01:39:02  robertj
 * Added assignement operator with RHS of PASN_BMPString to classes
 *   descended from PASN_BMPString.
 *
 * Revision 1.22  2001/06/14 02:14:12  robertj
 * Added functions to encode and decode another ASN type that is inside
 *   an octet string, useful for ANY or EXTERNAL types etc.
 *
 * Revision 1.21  2001/04/30 06:47:04  robertj
 * Fixed problem with en/decoding more than 16 extension fields in a sequence.
 *
 * Revision 1.20  2001/04/26 08:15:58  robertj
 * Fixed problem with ASN compile of single constraints on enumerations.
 *
 * Revision 1.19  2001/04/23 04:40:14  robertj
 * Added ASN standard types GeneralizedTime and UTCTime
 *
 * Revision 1.18  2001/04/12 03:25:22  robertj
 * Fixed PASN_Boolean cosntructor to be compatible with usage in ASN parser.
 * Changed all PASN_xxx types so constructor can take real type as only
 *   parameter. eg PASN_OctetString s = "fred";
 *
 * Revision 1.17  2001/03/21 03:32:35  robertj
 * Aded ability to get at the data bits buffer in a PASN_BitString
 *
 * Revision 1.16  2001/01/24 04:36:56  robertj
 * Added more bulletproofing to ASN structures to obey constraints.
 *
 * Revision 1.15  2000/10/26 11:09:07  robertj
 * More bullet proofing of PER decoder, changed bit type to be unsigned.
 *
 * Revision 1.14  2000/10/25 04:05:44  robertj
 * More bullet proofing of PER decoder.
 *
 * Revision 1.13  2000/07/11 18:23:03  robertj
 * Added ability to set/get BMP string data as PWORDArray.
 *
 * Revision 1.12  2000/04/10 17:30:42  robertj
 * Added [] operator for char access on ASN string classes.
 *
 * Revision 1.11  2000/02/29 06:32:12  robertj
 * Added ability to remove optional field in sequence, thanks Dave Harvey.
 *
 * Revision 1.10  1999/08/09 13:02:45  robertj
 * dded ASN compiler #defines for backward support of pre GCC 2.9 compilers.
 * Added ASN compiler #defines to reduce its memory footprint.
 *
 * Revision 1.9  1999/07/22 06:48:51  robertj
 * Added comparison operation to base ASN classes and compiled ASN code.
 * Added support for ANY type in ASN parser.
 *
 * Revision 1.8  1999/03/09 09:34:05  robertj
 * Fixed typo's.
 *
 * Revision 1.7  1999/03/09 08:01:46  robertj
 * Changed comments for doc++ support (more to come).
 *
 * Revision 1.6  1998/09/23 06:19:21  robertj
 * Added open source copyright license.
 *
 * Revision 1.5  1998/05/21 04:26:53  robertj
 * Fixed numerous PER problems.
 *
 * Revision 1.4  1998/05/07 05:19:28  robertj
 * Fixed problems with using copy constructor/assignment oeprator on PASN_Objects.
 *
 * Revision 1.3  1997/12/18 05:08:13  robertj
 * Added function to get choice discriminat`or name.
 *
 * Revision 1.2  1997/12/11 10:35:42  robertj
 * Support for new ASN file parser.
 *
 */

#ifndef _ASNER_H
#define _ASNER_H

#ifdef P_USE_PRAGMA
#pragma interface
#endif

// provide options to omit vertain encodings, if needed
#define     P_INCLUDE_PER
#define     P_INCLUDE_BER
#define     P_INCLUDE_XER

class PASN_Stream;
class PBER_Stream;
class PPER_Stream;

#if P_EXPAT
class PXER_Stream;
class PXMLElement;
#else
#undef      P_INCLUDE_XER
#endif

#include <ptlib.h>

/////////////////////////////////////////////////////////////////////////////

/** Base class for ASN encoding/decoding.
*/
class PASN_Object : public PObject
{
    PCLASSINFO(PASN_Object, PObject);
  public:
    /** Return a string giving the type of the object */
    virtual PString GetTypeAsString() const = 0;

    PINDEX GetObjectLength() const;
    virtual PINDEX GetDataLength() const = 0;
    virtual BOOL IsPrimitive() const { return TRUE; }

    virtual BOOL Decode(PASN_Stream &) = 0;
    virtual void Encode(PASN_Stream &) const = 0;

    BOOL IsExtendable() const { return extendable; }
    void SetExtendable(BOOL ext = TRUE) { extendable = ext; }

    enum TagClass {
      UniversalTagClass,
      ApplicationTagClass,
      ContextSpecificTagClass,
      PrivateTagClass,
      DefaultTagClass
    };
    TagClass GetTagClass() const { return tagClass; }

    enum UniversalTags {
      InvalidUniversalTag,
      UniversalBoolean,
      UniversalInteger,
      UniversalBitString,
      UniversalOctetString,
      UniversalNull,
      UniversalObjectId,
      UniversalObjectDescriptor,
      UniversalExternalType,
      UniversalReal,
      UniversalEnumeration,
      UniversalEmbeddedPDV,
      UniversalSequence = 16,
      UniversalSet,
      UniversalNumericString,
      UniversalPrintableString,
      UniversalTeletexString,
      UniversalVideotexString,
      UniversalIA5String,
      UniversalUTCTime,
      UniversalGeneralisedTime,
      UniversalGeneralizedTime = UniversalGeneralisedTime,
      UniversalGraphicString,
      UniversalVisibleString,
      UniversalGeneralString,
      UniversalUniversalString,
      UniversalBMPString = 30
    };

    unsigned GetTag() const  { return tag; }
    virtual void SetTag(unsigned newTag, TagClass tagClass = DefaultTagClass);

    enum ConstraintType {
      Unconstrained,
      PartiallyConstrained,
      FixedConstraint,
      ExtendableConstraint
    };

    enum MinimumValueTag { MinimumValue = INT_MIN };
    enum MaximumValueTag { MaximumValue = INT_MAX };
    void SetConstraints(ConstraintType type, int value)
      { SetConstraintBounds(type, value, value); }
    void SetConstraints(ConstraintType, int lower, MaximumValueTag /*upper*/)
      { SetConstraintBounds(PartiallyConstrained, (int)lower, lower < 0 ? INT_MAX : UINT_MAX); }
    void SetConstraints(ConstraintType, MinimumValueTag lower, unsigned upper)
      { SetConstraintBounds(PartiallyConstrained, (int)lower, (unsigned)upper); }
    void SetConstraints(ConstraintType, MinimumValueTag lower, MaximumValueTag upper)
      { SetConstraintBounds(PartiallyConstrained, (int)lower, (unsigned)upper); }
    void SetConstraints(ConstraintType type, int lower, unsigned upper)
      { SetConstraintBounds(type, lower, upper); }

    virtual void SetConstraintBounds(ConstraintType type, int lower, unsigned upper);
    virtual void SetCharacterSet(ConstraintType ctype, const char * charSet);
    virtual void SetCharacterSet(ConstraintType ctype, unsigned firstChar, unsigned lastChar);

    static PINDEX GetMaximumArraySize();
    static void SetMaximumArraySize(PINDEX sz);
    static PINDEX GetMaximumStringSize();
    static void SetMaximumStringSize(PINDEX sz);

  protected:
    PASN_Object(unsigned tag, TagClass tagClass, BOOL extend = FALSE);

    /// PER extension capability
    BOOL extendable;
    /// BER tag class
    TagClass tagClass;
    /// ASN object tag
    unsigned tag;
};


/** Base class for constrained ASN encoding/decoding.
*/
class PASN_ConstrainedObject : public PASN_Object
{
    PCLASSINFO(PASN_ConstrainedObject, PASN_Object);
  public:
    BOOL IsConstrained() const { return constraint != Unconstrained; }
    int GetLowerLimit() const { return lowerLimit; }
    unsigned GetUpperLimit() const { return upperLimit; }

    BOOL ConstrainedLengthDecode(PPER_Stream & strm, unsigned & length);
    void ConstrainedLengthEncode(PPER_Stream & strm, unsigned length) const;

    BOOL ConstraintEncode(PPER_Stream & strm, unsigned value) const;

  protected:
    virtual void SetConstraintBounds(ConstraintType type, int lower, unsigned upper);
    PASN_ConstrainedObject(unsigned tag, TagClass tagClass);

    ConstraintType constraint;
    int lowerLimit;
    unsigned upperLimit;
};


/** Class for ASN Null type.
*/
class PASN_Null : public PASN_Object
{
    PCLASSINFO(PASN_Null, PASN_Object);
  public:
    PASN_Null(unsigned tag = UniversalNull,
              TagClass tagClass = UniversalTagClass);

    virtual Comparison Compare(const PObject & obj) const;
    virtual PObject * Clone() const;
    virtual void PrintOn(ostream & strm) const;

    virtual PString GetTypeAsString() const;
    virtual PINDEX GetDataLength() const;
    virtual BOOL Decode(PASN_Stream &);
    virtual void Encode(PASN_Stream &) const;
};


/** Class for ASN Boolean type.
*/
class PASN_Boolean : public PASN_Object
{
    PCLASSINFO(PASN_Boolean, PASN_Object);
  public:
    PASN_Boolean(BOOL val = FALSE);
    PASN_Boolean(unsigned tag, TagClass tagClass, BOOL val = FALSE);

    PASN_Boolean & operator=(BOOL v) { value = v; return *this; }
    operator BOOL() const { return value; }
    BOOL GetValue() const { return value; }
    void SetValue(BOOL v) { value = v; }

    virtual Comparison Compare(const PObject & obj) const;
    virtual PObject * Clone() const;
    virtual void PrintOn(ostream & strm) const;

    virtual PString GetTypeAsString() const;
    virtual PINDEX GetDataLength() const;
    virtual BOOL Decode(PASN_Stream &);
    virtual void Encode(PASN_Stream &) const;

  protected:
    BOOL value;
};


/** Class for ASN Integer type.