Add new classes in Math.Field and some other EC-related stuff from Java

1 files changed, 63 insertions, 0 deletions

diff --git a/crypto/src/math/field/GenericPolynomialExtensionField.cs b/crypto/src/math/field/GenericPolynomialExtensionField.cs
new file mode 100644

index 000000000..13ef57165
--- /dev/null
+++ b/crypto/src/math/field/GenericPolynomialExtensionField.cs
@@ -0,0 +1,63 @@
+using System;
+
+using Org.BouncyCastle.Utilities;
+
+namespace Org.BouncyCastle.Math.Field
+{
+    internal class GenericPolynomialExtensionField
+        : IPolynomialExtensionField
+    {
+        protected readonly IFiniteField subfield;
+        protected readonly IPolynomial minimalPolynomial;
+
+        internal GenericPolynomialExtensionField(IFiniteField subfield, IPolynomial polynomial)
+        {
+            this.subfield = subfield;
+            this.minimalPolynomial = polynomial;
+        }
+
+        public virtual BigInteger Characteristic
+        {
+            get { return subfield.Characteristic; }
+        }
+
+        public virtual int Dimension
+        {
+            get { return subfield.Dimension * minimalPolynomial.Degree; }
+        }
+
+        public virtual IFiniteField Subfield
+        {
+            get { return subfield; }
+        }
+
+        public virtual int Degree
+        {
+            get { return minimalPolynomial.Degree; }
+        }
+
+        public virtual IPolynomial MinimalPolynomial
+        {
+            get { return minimalPolynomial; }
+        }
+
+        public override bool Equals(object obj)
+        {
+            if (this == obj)
+            {
+                return true;
+            }
+            GenericPolynomialExtensionField other = obj as GenericPolynomialExtensionField;
+            if (null == other)
+            {
+                return false;
+            }
+            return subfield.Equals(other.subfield) && minimalPolynomial.Equals(other.minimalPolynomial);
+        }
+
+        public override int GetHashCode()
+        {
+            return subfield.GetHashCode() ^ Integers.RotateLeft(minimalPolynomial.GetHashCode(), 16);
+        }
+    }
+}