EncryptedData.cs :  » PDF » iTextSharp » Org » BouncyCastle » Asn1 » Pkcs » C# / CSharp Open Source

using System;

using Org.BouncyCastle.Asn1.X509;

namespace Org.BouncyCastle.Asn1.Pkcs{
    /**
     * The EncryptedData object.
     * <pre>
     *      EncryptedData ::= Sequence {
     *           version Version,
     *           encryptedContentInfo EncryptedContentInfo
     *      }
     *
     *
     *      EncryptedContentInfo ::= Sequence {
     *          contentType ContentType,
     *          contentEncryptionAlgorithm  ContentEncryptionAlgorithmIdentifier,
     *          encryptedContent [0] IMPLICIT EncryptedContent OPTIONAL
     *    }
     *
     *    EncryptedContent ::= OCTET STRING
     * </pre>
     */
    public class EncryptedData
        : Asn1Encodable
    {
        private readonly Asn1Sequence data;
//        private readonly DerObjectIdentifier bagId;
//        private readonly Asn1Object bagValue;

    public static EncryptedData GetInstance(
             object obj)
        {
      if (obj is EncryptedData)
      {
        return (EncryptedData) obj;
      }

      if (obj is Asn1Sequence)
      {
        return new EncryptedData((Asn1Sequence) obj);
      }

      throw new ArgumentException("Unknown object in factory: " + obj.GetType().FullName, "obj");
    }

    private EncryptedData(
            Asn1Sequence seq)
        {
      if (seq.Count != 2)
        throw new ArgumentException("Wrong number of elements in sequence", "seq");

      int version = ((DerInteger) seq[0]).Value.IntValue;
      if (version != 0)
            {
                throw new ArgumentException("sequence not version 0");
            }

      this.data = (Asn1Sequence) seq[1];
        }

    public EncryptedData(
            DerObjectIdentifier  contentType,
            AlgorithmIdentifier  encryptionAlgorithm,
            Asn1Encodable    content)
        {
      data = new BerSequence(
        contentType,
        encryptionAlgorithm.ToAsn1Object(),
        new BerTaggedObject(false, 0, content));
        }

    public DerObjectIdentifier ContentType
        {
            get { return (DerObjectIdentifier) data[0]; }
        }

    public AlgorithmIdentifier EncryptionAlgorithm
        {
      get { return AlgorithmIdentifier.GetInstance(data[1]); }
        }

    public Asn1OctetString Content
        {
      get
      {
        if (data.Count == 3)
        {
          DerTaggedObject o = (DerTaggedObject) data[2];

          return Asn1OctetString.GetInstance(o.GetObject());
        }

        return null;
      }
        }

    public override Asn1Object ToAsn1Object()
        {
      return new BerSequence(new DerInteger(0), data);
        }
    }
}