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

using System;

using Org.BouncyCastle.Asn1.X509;

namespace Org.BouncyCastle.Asn1.Cms{
  /**
   * Produce an object suitable for an Asn1OutputStream.
   * <pre>
   * AuthenticatedData ::= SEQUENCE {
   *       version CMSVersion,
   *       originatorInfo [0] IMPLICIT OriginatorInfo OPTIONAL,
   *       recipientInfos RecipientInfos,
   *       macAlgorithm MessageAuthenticationCodeAlgorithm,
   *       digestAlgorithm [1] DigestAlgorithmIdentifier OPTIONAL,
   *       encapContentInfo EncapsulatedContentInfo,
   *       authAttrs [2] IMPLICIT AuthAttributes OPTIONAL,
   *       mac MessageAuthenticationCode,
   *       unauthAttrs [3] IMPLICIT UnauthAttributes OPTIONAL }
   *
   * AuthAttributes ::= SET SIZE (1..MAX) OF Attribute
   *
   * UnauthAttributes ::= SET SIZE (1..MAX) OF Attribute
   *
   * MessageAuthenticationCode ::= OCTET STRING
   * </pre>
   */
  public class AuthenticatedDataParser
  {
      private Asn1SequenceParser  seq;
      private DerInteger      version;
      private IAsn1Convertible  nextObject;
      private bool        originatorInfoCalled;

      public AuthenticatedDataParser(
          Asn1SequenceParser  seq)
      {
          this.seq = seq;
          this.version = (DerInteger)seq.ReadObject();
      }

      public DerInteger Version
      {
          get { return version; }
      }

      public OriginatorInfo GetOriginatorInfo()
      {
          originatorInfoCalled = true;

          if (nextObject == null)
          {
              nextObject = seq.ReadObject();
          }

          if (nextObject is Asn1TaggedObjectParser && ((Asn1TaggedObjectParser)nextObject).TagNo == 0)
          {
              Asn1SequenceParser originatorInfo = (Asn1SequenceParser) ((Asn1TaggedObjectParser)nextObject).GetObjectParser(Asn1Tags.Sequence, false);
              nextObject = null;
              return OriginatorInfo.GetInstance(originatorInfo.ToAsn1Object());
          }

          return null;
      }

      public Asn1SetParser GetRecipientInfos()
      {
          if (!originatorInfoCalled)
          {
              GetOriginatorInfo();
          }

          if (nextObject == null)
          {
              nextObject = seq.ReadObject();
          }

          Asn1SetParser recipientInfos = (Asn1SetParser)nextObject;
          nextObject = null;
          return recipientInfos;
      }

      public AlgorithmIdentifier GetMacAlgorithm()
      {
          if (nextObject == null)
          {
              nextObject = seq.ReadObject();
          }

          if (nextObject != null)
          {
              Asn1SequenceParser o = (Asn1SequenceParser)nextObject;
              nextObject = null;
              return AlgorithmIdentifier.GetInstance(o.ToAsn1Object());
          }

          return null;
      }

      public ContentInfoParser GetEnapsulatedContentInfo()
      {
          if (nextObject == null)
          {
              nextObject = seq.ReadObject();
          }

          if (nextObject != null)
          {
              Asn1SequenceParser o = (Asn1SequenceParser)nextObject;
              nextObject = null;
              return new ContentInfoParser(o);
          }

          return null;
      }

      public Asn1SetParser GetAuthAttrs()
      {
          if (nextObject == null)
          {
              nextObject = seq.ReadObject();
          }

          if (nextObject is Asn1TaggedObjectParser)
          {
              IAsn1Convertible o = nextObject;
              nextObject = null;
              return (Asn1SetParser)((Asn1TaggedObjectParser)o).GetObjectParser(Asn1Tags.Set, false);
          }

          return null;
      }

      public Asn1OctetString GetMac()
      {
          if (nextObject == null)
          {
              nextObject = seq.ReadObject();
          }

          IAsn1Convertible o = nextObject;
          nextObject = null;

          return Asn1OctetString.GetInstance(o.ToAsn1Object());
      }

      public Asn1SetParser GetUnauthAttrs()
      {
          if (nextObject == null)
          {
              nextObject = seq.ReadObject();
          }

          if (nextObject != null)
          {
              IAsn1Convertible o = nextObject;
              nextObject = null;
              return (Asn1SetParser)((Asn1TaggedObjectParser)o).GetObjectParser(Asn1Tags.Set, false);
          }

          return null;
      }
  }
}