diff --git a/Crypto/src/asn1/x9/X9ECParameters.cs b/Crypto/src/asn1/x9/X9ECParameters.cs
new file mode 100644
index 000000000..d025b36ce
--- /dev/null
+++ b/Crypto/src/asn1/x9/X9ECParameters.cs
@@ -0,0 +1,170 @@
+using System;
+
+using Org.BouncyCastle.Math;
+using Org.BouncyCastle.Math.EC;
+
+namespace Org.BouncyCastle.Asn1.X9
+{
+ /**
+ * ASN.1 def for Elliptic-Curve ECParameters structure. See
+ * X9.62, for further details.
+ */
+ public class X9ECParameters
+ : Asn1Encodable
+ {
+ private X9FieldID fieldID;
+ private ECCurve curve;
+ private ECPoint g;
+ private BigInteger n;
+ private BigInteger h;
+ private byte[] seed;
+
+ public X9ECParameters(
+ Asn1Sequence seq)
+ {
+ if (!(seq[0] is DerInteger)
+ || !((DerInteger) seq[0]).Value.Equals(BigInteger.One))
+ {
+ throw new ArgumentException("bad version in X9ECParameters");
+ }
+
+ X9Curve x9c = null;
+ if (seq[2] is X9Curve)
+ {
+ x9c = (X9Curve) seq[2];
+ }
+ else
+ {
+ x9c = new X9Curve(
+ new X9FieldID(
+ (Asn1Sequence) seq[1]),
+ (Asn1Sequence) seq[2]);
+ }
+
+ this.curve = x9c.Curve;
+
+ if (seq[3] is X9ECPoint)
+ {
+ this.g = ((X9ECPoint) seq[3]).Point;
+ }
+ else
+ {
+ this.g = new X9ECPoint(curve, (Asn1OctetString) seq[3]).Point;
+ }
+
+ this.n = ((DerInteger) seq[4]).Value;
+ this.seed = x9c.GetSeed();
+
+ if (seq.Count == 6)
+ {
+ this.h = ((DerInteger) seq[5]).Value;
+ }
+ }
+
+ public X9ECParameters(
+ ECCurve curve,
+ ECPoint g,
+ BigInteger n)
+ : this(curve, g, n, BigInteger.One, null)
+ {
+ }
+
+ public X9ECParameters(
+ ECCurve curve,
+ ECPoint g,
+ BigInteger n,
+ BigInteger h)
+ : this(curve, g, n, h, null)
+ {
+ }
+
+ public X9ECParameters(
+ ECCurve curve,
+ ECPoint g,
+ BigInteger n,
+ BigInteger h,
+ byte[] seed)
+ {
+ this.curve = curve;
+ this.g = g;
+ this.n = n;
+ this.h = h;
+ this.seed = seed;
+
+ if (curve is FpCurve)
+ {
+ this.fieldID = new X9FieldID(((FpCurve) curve).Q);
+ }
+ else if (curve is F2mCurve)
+ {
+ F2mCurve curveF2m = (F2mCurve) curve;
+ this.fieldID = new X9FieldID(curveF2m.M, curveF2m.K1,
+ curveF2m.K2, curveF2m.K3);
+ }
+ }
+
+ public ECCurve Curve
+ {
+ get { return curve; }
+ }
+
+ public ECPoint G
+ {
+ get { return g; }
+ }
+
+ public BigInteger N
+ {
+ get { return n; }
+ }
+
+ public BigInteger H
+ {
+ get
+ {
+ if (h == null)
+ {
+ // TODO - this should be calculated, it will cause issues with custom curves.
+ return BigInteger.One;
+ }
+
+ return h;
+ }
+ }
+
+ public byte[] GetSeed()
+ {
+ return seed;
+ }
+
+ /**
+ * Produce an object suitable for an Asn1OutputStream.
+ * <pre>
+ * ECParameters ::= Sequence {
+ * version Integer { ecpVer1(1) } (ecpVer1),
+ * fieldID FieldID {{FieldTypes}},
+ * curve X9Curve,
+ * base X9ECPoint,
+ * order Integer,
+ * cofactor Integer OPTIONAL
+ * }
+ * </pre>
+ */
+ public override Asn1Object ToAsn1Object()
+ {
+ Asn1EncodableVector v = new Asn1EncodableVector(
+ new DerInteger(1),
+ fieldID,
+ new X9Curve(curve, seed),
+ new X9ECPoint(g),
+ new DerInteger(n));
+
+ if (h != null)
+ {
+ v.Add(new DerInteger(h));
+ }
+
+ return new DerSequence(v);
+ }
+ }
+}
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