X509EnhancedKeyUsageExtension.cs :  » 2.6.4-mono-.net-core » System.Security » System » Security » Cryptography » X509Certificates » C# / CSharp Open Source

//
// System.Security.Cryptography.X509EnhancedKeyUsageExtension
//
// Author:
//  Sebastien Pouliot  <sebastien@ximian.com>
//
// Copyright (C) 2005 Novell, Inc (http://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.
//

#if SECURITY_DEP || MOONLIGHT

using System.Text;

using Mono.Security;

namespace System.Security.Cryptography.X509Certificates{

  public sealed class X509EnhancedKeyUsageExtension : X509Extension {

    internal const string oid = "2.5.29.37";
    internal const string friendlyName = "Enhanced Key Usage";

    private OidCollection _enhKeyUsage;
    private AsnDecodeStatus _status;

    // constructors

    public X509EnhancedKeyUsageExtension ()
    {
      _oid = new Oid (oid, friendlyName);
    }

    public X509EnhancedKeyUsageExtension (AsnEncodedData encodedEnhancedKeyUsages, bool critical)
    {
      // ignore the Oid provided by encodedKeyUsage (our rules!)
      _oid = new Oid (oid, friendlyName);
      _raw = encodedEnhancedKeyUsages.RawData;
      base.Critical = critical;
      _status = Decode (this.RawData);
    }

    public X509EnhancedKeyUsageExtension (OidCollection enhancedKeyUsages, bool critical)
    {
      if (enhancedKeyUsages == null)
        throw new ArgumentNullException ("enhancedKeyUsages");

      _oid = new Oid (oid, friendlyName);
      base.Critical = critical;
      _enhKeyUsage = enhancedKeyUsages.ReadOnlyCopy ();
      RawData = Encode ();
    }

    // properties

    public OidCollection EnhancedKeyUsages {
      get {
        switch (_status) {
        case AsnDecodeStatus.Ok:
        case AsnDecodeStatus.InformationNotAvailable:
          if (_enhKeyUsage == null)
            _enhKeyUsage = new OidCollection ();
          _enhKeyUsage.ReadOnly = true;
          return _enhKeyUsage;
        default:
          throw new CryptographicException ("Badly encoded extension.");
        }
      }
    }

    // methods

    public override void CopyFrom (AsnEncodedData asnEncodedData) 
    {
      if (asnEncodedData == null)
        throw new ArgumentNullException ("encodedData");

      X509Extension ex = (asnEncodedData as X509Extension);
      if (ex == null)
        throw new ArgumentException (Locale.GetText ("Wrong type."), "asnEncodedData");

      if (ex._oid == null)
        _oid = new Oid (oid, friendlyName);
      else 
        _oid = new Oid (ex._oid);

      RawData = ex.RawData;
      base.Critical = ex.Critical;
      // and we deal with the rest later
      _status = Decode (this.RawData);
    }

    // internal

    internal AsnDecodeStatus Decode (byte[] extension)
    {
      if ((extension == null) || (extension.Length == 0))
        return AsnDecodeStatus.BadAsn;
      if (extension [0] != 0x30)
        return AsnDecodeStatus.BadTag;

      if (_enhKeyUsage == null)
        _enhKeyUsage = new OidCollection ();

      try {
        ASN1 ex = new ASN1 (extension);
        if (ex.Tag != 0x30)
          throw new CryptographicException (Locale.GetText ("Invalid ASN.1 Tag"));
        for (int i=0; i < ex.Count; i++) {
          _enhKeyUsage.Add (new Oid (ASN1Convert.ToOid (ex [i])));
        }
      }
      catch {
        return AsnDecodeStatus.BadAsn;
      }

      return AsnDecodeStatus.Ok;
    }

    internal byte[] Encode ()
    {
      ASN1 ex = new ASN1 (0x30);
      foreach (Oid oid in _enhKeyUsage) {
        ex.Add (ASN1Convert.FromOid (oid.Value));
      }
      return ex.GetBytes ();
    }

    internal override string ToString (bool multiLine)
    {
      switch (_status) {
      case AsnDecodeStatus.BadAsn:
        return String.Empty;
      case AsnDecodeStatus.BadTag:
      case AsnDecodeStatus.BadLength:
        return FormatUnkownData (_raw);
      case AsnDecodeStatus.InformationNotAvailable:
        return "Information Not Available";
      }

      if (_oid.Value != oid)
        return String.Format ("Unknown Key Usage ({0})", _oid.Value);
      if (_enhKeyUsage.Count == 0)
        return "Information Not Available";

      StringBuilder sb = new StringBuilder ();

      for (int i=0; i < _enhKeyUsage.Count; i++) {
        Oid o = _enhKeyUsage [i];
        switch (o.Value) {
        case "1.3.6.1.5.5.7.3.1":
          sb.Append ("Server Authentication (");
          break;
        default:
          sb.Append ("Unknown Key Usage (");
          break;
        }
        sb.Append (o.Value);
        sb.Append (")");

        if (multiLine)
          sb.Append (Environment.NewLine);
        else if (i != (_enhKeyUsage.Count - 1))
          sb.Append (", ");
      }

      return sb.ToString ();
    }
  }
}

#endif