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

using System;

namespace Org.BouncyCastle.Asn1.Cms{
  public class EncryptedData
    : Asn1Encodable
  {
    private readonly DerInteger        version;
    private readonly EncryptedContentInfo  encryptedContentInfo;
    private readonly Asn1Set        unprotectedAttrs;

    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("Invalid EncryptedData: " + obj.GetType().Name);
    }

    public EncryptedData(
      EncryptedContentInfo encInfo)
      : this(encInfo, null)
    {
    }

    public EncryptedData(
      EncryptedContentInfo  encInfo,
      Asn1Set          unprotectedAttrs)
    {
      if (encInfo == null)
        throw new ArgumentNullException("encInfo");

      this.version = new DerInteger((unprotectedAttrs == null) ? 0 : 2);
      this.encryptedContentInfo = encInfo;
      this.unprotectedAttrs = unprotectedAttrs;
    }

    private EncryptedData(
      Asn1Sequence seq)
    {
      if (seq == null)
        throw new ArgumentNullException("seq");
      if (seq.Count < 2 || seq.Count > 3)
        throw new ArgumentException("Bad sequence size: " + seq.Count, "seq");

      this.version = DerInteger.GetInstance(seq[0]);
      this.encryptedContentInfo = EncryptedContentInfo.GetInstance(seq[1]);

      if (seq.Count > 2)
      {
        this.unprotectedAttrs = Asn1Set.GetInstance(seq[2]);
      }
    }

    public virtual DerInteger Version
    {
      get { return version; }
    }

    public virtual EncryptedContentInfo EncryptedContentInfo
    {
      get { return encryptedContentInfo; }
    }

    public virtual Asn1Set UnprotectedAttrs
    {
      get { return unprotectedAttrs; }
    }

    /**
    * <pre>
    *       EncryptedData ::= SEQUENCE {
    *                     version CMSVersion,
    *                     encryptedContentInfo EncryptedContentInfo,
    *                     unprotectedAttrs [1] IMPLICIT UnprotectedAttributes OPTIONAL }
    * </pre>
    * @return a basic ASN.1 object representation.
    */
    public override Asn1Object ToAsn1Object()
    {
      Asn1EncodableVector v = new Asn1EncodableVector(version, encryptedContentInfo);

      if (unprotectedAttrs != null)
      {
        v.Add(new BerTaggedObject(false, 1, unprotectedAttrs));
      }

      return new BerSequence(v);
    }
  }
}