DSAParameter.cs :  » PDF » iTextSharp » Org » BouncyCastle » Asn1 » X509 » C# / CSharp Open Source

using System;
using System.Collections;

using Org.BouncyCastle.Math;

namespace Org.BouncyCastle.Asn1.X509{
    public class DsaParameter
        : Asn1Encodable
    {
        internal readonly DerInteger p, q, g;

    public static DsaParameter GetInstance(
            Asn1TaggedObject  obj,
            bool        explicitly)
        {
            return GetInstance(Asn1Sequence.GetInstance(obj, explicitly));
        }

    public static DsaParameter GetInstance(
            object obj)
        {
            if(obj == null || obj is DsaParameter)
            {
                return (DsaParameter) obj;
            }

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

      throw new ArgumentException("Invalid DsaParameter: " + obj.GetType().Name);
        }

    public DsaParameter(
            BigInteger  p,
            BigInteger  q,
            BigInteger  g)
        {
            this.p = new DerInteger(p);
            this.q = new DerInteger(q);
            this.g = new DerInteger(g);
        }

    private DsaParameter(
            Asn1Sequence seq)
        {
      if (seq.Count != 3)
        throw new ArgumentException("Bad sequence size: " + seq.Count, "seq");

      this.p = DerInteger.GetInstance(seq[0]);
      this.q = DerInteger.GetInstance(seq[1]);
      this.g = DerInteger.GetInstance(seq[2]);
        }

    public BigInteger P
    {
      get { return p.PositiveValue; }
    }

    public BigInteger Q
    {
      get { return q.PositiveValue; }
    }

    public BigInteger G
    {
      get { return g.PositiveValue; }
    }

    public override Asn1Object ToAsn1Object()
        {
      return new DerSequence(p, q, g);
        }
    }
}