Jo Shields a575963da9 Imported Upstream version 3.6.0
Former-commit-id: da6be194a6b1221998fc28233f2503bd61dd9d14
2014-08-13 10:39:27 +01:00

327 lines
8.0 KiB
C#

/******************************************************************************
* The MIT License
* Copyright (c) 2003 Novell Inc. www.novell.com
*
* 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, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED AS IS, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*******************************************************************************/
//
// Novell.Directory.Ldap.Asn1.Asn1Identifier.cs
//
// Author:
// Sunil Kumar (Sunilk@novell.com)
//
// (C) 2003 Novell, Inc (http://www.novell.com)
//
using System;
namespace Novell.Directory.Ldap.Asn1
{
/// <summary> This class is used to encapsulate an ASN.1 Identifier.
///
/// An Asn1Identifier is composed of three parts:
/// <li> a class type,</li>
/// <li> a form, and</li>
/// <li> a tag.</li>
///
/// The class type is defined as:
/// <pre>
/// bit 8 7 TAG CLASS
/// ------- -----------
/// 0 0 UNIVERSAL
/// 0 1 APPLICATION
/// 1 0 CONTEXT
/// 1 1 PRIVATE
/// </pre>
/// The form is defined as:
/// <pre>
/// bit 6 FORM
/// ----- --------
/// 0 PRIMITIVE
/// 1 CONSTRUCTED
/// </pre>
///
/// Note: CONSTRUCTED types are made up of other CONSTRUCTED or PRIMITIVE
/// types.
///
/// The tag is defined as:
/// <pre>
/// bit 5 4 3 2 1 TAG
/// ------------- ---------------------------------------------
/// 0 0 0 0 0
/// . . . . .
/// 1 1 1 1 0 (0-30) single octet tag
///
/// 1 1 1 1 1 (> 30) multiple octet tag, more octets follow
/// </pre>
/// </summary>
public class Asn1Identifier:System.Object, System.ICloneable
{
/// <summary> Returns the CLASS of this Asn1Identifier as an int value.
///
/// </summary>
/// <seealso cref="UNIVERSAL">
/// </seealso>
/// <seealso cref="APPLICATION">
/// </seealso>
/// <seealso cref="CONTEXT">
/// </seealso>
/// <seealso cref="PRIVATE">
/// </seealso>
virtual public int Asn1Class
{
get
{
return tagClass;
}
}
/// <summary> Return a boolean indicating if the constructed bit is set.
///
/// </summary>
/// <returns> true if constructed and false if primitive.
/// </returns>
virtual public bool Constructed
{
get
{
return constructed;
}
}
/// <summary> Returns the TAG of this Asn1Identifier.</summary>
virtual public int Tag
{
get
{
return tag;
}
}
/// <summary> Returns the encoded length of this Asn1Identifier.</summary>
virtual public int EncodedLength
{
get
{
return encodedLength;
}
}
/// <summary> Returns a boolean value indicating whether or not this Asn1Identifier
/// has a TAG CLASS of UNIVERSAL.
///
/// </summary>
/// <seealso cref="UNIVERSAL">
/// </seealso>
[CLSCompliantAttribute(false)]
virtual public bool Universal
{
get
{
return tagClass == UNIVERSAL;
}
}
/// <summary> Returns a boolean value indicating whether or not this Asn1Identifier
/// has a TAG CLASS of APPLICATION.
///
/// </summary>
/// <seealso cref="APPLICATION">
/// </seealso>
[CLSCompliantAttribute(false)]
virtual public bool Application
{
get
{
return tagClass == APPLICATION;
}
}
/// <summary> Returns a boolean value indicating whether or not this Asn1Identifier
/// has a TAG CLASS of CONTEXT-SPECIFIC.
///
/// </summary>
/// <seealso cref="CONTEXT">
/// </seealso>
[CLSCompliantAttribute(false)]
virtual public bool Context
{
get
{
return tagClass == CONTEXT;
}
}
/// <summary> Returns a boolean value indicating whether or not this Asn1Identifier
/// has a TAG CLASS of PRIVATE.
///
/// </summary>
/// <seealso cref="PRIVATE"></seealso>
[CLSCompliantAttribute(false)]
virtual public bool Private
{
get
{
return tagClass == PRIVATE;
}
}
/// <summary> Universal tag class.
///
/// UNIVERSAL = 0
/// </summary>
public const int UNIVERSAL = 0;
/// <summary> Application-wide tag class.
///
/// APPLICATION = 1
/// </summary>
public const int APPLICATION = 1;
/// <summary> Context-specific tag class.
///
/// CONTEXT = 2
/// </summary>
public const int CONTEXT = 2;
/// <summary> Private-use tag class.
///
/// PRIVATE = 3
/// </summary>
public const int PRIVATE = 3;
/* Private variables
*/
private int tagClass;
private bool constructed;
private int tag;
private int encodedLength;
/* Constructors for Asn1Identifier
*/
/// <summary> Constructs an Asn1Identifier using the classtype, form and tag.
///
/// </summary>
/// <param name="tagClass">As defined above.
///
/// </param>
/// <param name="constructed">Set to true if constructed and false if primitive.
///
/// </param>
/// <param name="tag">The tag of this identifier
/// </param>
public Asn1Identifier(int tagClass, bool constructed, int tag)
{
this.tagClass = tagClass;
this.constructed = constructed;
this.tag = tag;
}
/// <summary> Decode an Asn1Identifier directly from an InputStream and
/// save the encoded length of the Asn1Identifier.
///
/// </summary>
/// <param name="in">The input stream to decode from.
/// </param>
public Asn1Identifier(System.IO.Stream in_Renamed)
{
int r = in_Renamed.ReadByte();
encodedLength++;
if (r < 0)
throw new System.IO.EndOfStreamException("BERDecoder: decode: EOF in Identifier");
tagClass = r >> 6;
constructed = (r & 0x20) != 0;
tag = r & 0x1F; // if tag < 30 then its a single octet identifier.
if (tag == 0x1F)
// if true, its a multiple octet identifier.
tag = decodeTagNumber(in_Renamed);
return ;
}
public Asn1Identifier()
{
return ;
}
/// <summary> Decode an Asn1Identifier directly from an InputStream and
/// save the encoded length of the Asn1Identifier, but reuse the object.
///
/// </summary>
/// <param name="in">The input stream to decode from.
/// </param>
public void reset(System.IO.Stream in_Renamed)
{
encodedLength = 0;
int r = in_Renamed.ReadByte();
encodedLength++;
if (r < 0)
throw new System.IO.EndOfStreamException("BERDecoder: decode: EOF in Identifier");
tagClass = r >> 6;
constructed = (r & 0x20) != 0;
tag = r & 0x1F; // if tag < 30 then its a single octet identifier.
if (tag == 0x1F)
// if true, its a multiple octet identifier.
tag = decodeTagNumber(in_Renamed);
}
/// <summary> In the case that we have a tag number that is greater than 30, we need
/// to decode a multiple octet tag number.
/// </summary>
private int decodeTagNumber(System.IO.Stream in_Renamed)
{
int n = 0;
while (true)
{
int r = in_Renamed.ReadByte();
encodedLength++;
if (r < 0)
throw new System.IO.EndOfStreamException("BERDecoder: decode: EOF in tag number");
n = (n << 7) + (r & 0x7F);
if ((r & 0x80) == 0)
break;
}
return n;
}
/* Convenience methods
*/
/// <summary> Creates a duplicate, not a true clone, of this object and returns
/// a reference to the duplicate.
///
/// </summary>
public System.Object Clone()
{
try
{
return base.MemberwiseClone();
}
catch (System.Exception ce)
{
throw new System.SystemException("Internal error, cannot create clone");
}
}
}
}