1 files changed, 79 insertions, 0 deletions
diff --git a/crypto/src/asn1/cmp/Challenge.cs b/crypto/src/asn1/cmp/Challenge.cs
new file mode 100644
index 000000000..bee5f96f5
--- /dev/null
+++ b/crypto/src/asn1/cmp/Challenge.cs
@@ -0,0 +1,79 @@
+using System;
+
+using Org.BouncyCastle.Asn1.X509;
+
+namespace Org.BouncyCastle.Asn1.Cmp
+{
+	public class Challenge
+		: Asn1Encodable
+	{
+		private readonly AlgorithmIdentifier owf;
+		private readonly Asn1OctetString witness;
+		private readonly Asn1OctetString challenge;
+
+		private Challenge(Asn1Sequence seq)
+		{
+			int index = 0;
+
+			if (seq.Count == 3)
+			{
+				owf = AlgorithmIdentifier.GetInstance(seq[index++]);
+			}
+
+			witness = Asn1OctetString.GetInstance(seq[index++]);
+			challenge = Asn1OctetString.GetInstance(seq[index]);
+		}
+
+		public static Challenge GetInstance(object obj)
+		{
+			if (obj is Challenge)
+				return (Challenge)obj;
+
+			if (obj is Asn1Sequence)
+				return new Challenge((Asn1Sequence)obj);
+
+			throw new ArgumentException("Invalid object: " + obj.GetType().Name, "obj");
+		}
+
+		public virtual AlgorithmIdentifier Owf
+		{
+			get { return owf; }
+		}
+
+		/**
+		 * <pre>
+		 * Challenge ::= SEQUENCE {
+		 *                 owf                 AlgorithmIdentifier  OPTIONAL,
+		 *
+		 *                 -- MUST be present in the first Challenge; MAY be omitted in
+		 *                 -- any subsequent Challenge in POPODecKeyChallContent (if
+		 *                 -- omitted, then the owf used in the immediately preceding
+		 *                 -- Challenge is to be used).
+		 *
+		 *                 witness             OCTET STRING,
+		 *                 -- the result of applying the one-way function (owf) to a
+		 *                 -- randomly-generated INTEGER, A.  [Note that a different
+		 *                 -- INTEGER MUST be used for each Challenge.]
+		 *                 challenge           OCTET STRING
+		 *                 -- the encryption (under the public key for which the cert.
+		 *                 -- request is being made) of Rand, where Rand is specified as
+		 *                 --   Rand ::= SEQUENCE {
+		 *                 --      int      INTEGER,
+		 *                 --       - the randomly-generated INTEGER A (above)
+		 *                 --      sender   GeneralName
+		 *                 --       - the sender's name (as included in PKIHeader)
+		 *                 --   }
+		 *      }
+		 * </pre>
+		 * @return a basic ASN.1 object representation.
+		 */
+		public override Asn1Object ToAsn1Object()
+		{
+			Asn1EncodableVector v = new Asn1EncodableVector();
+			v.AddOptional(owf);
+			v.Add(witness);
+			v.Add(challenge);
+			return new DerSequence(v);
+		}
+	}
+}