From 70b47a3c76303a3af17c9ed635f7f1fa8a78ad18 Mon Sep 17 00:00:00 2001
From: Peter Dettman <peter.dettman@bouncycastle.org>
Date: Mon, 1 Jul 2024 16:15:42 +0700
Subject: Refactoring in Asn1.Oiw

---
 crypto/src/asn1/oiw/ElGamalParameter.cs  | 61 ++++++++++++++++++++------------
 crypto/src/security/PrivateKeyFactory.cs |  3 +-
 crypto/src/security/PublicKeyFactory.cs  |  3 +-
 crypto/test/src/test/ElGamalTest.cs      |  2 +-
 4 files changed, 41 insertions(+), 28 deletions(-)

(limited to 'crypto')

diff --git a/crypto/src/asn1/oiw/ElGamalParameter.cs b/crypto/src/asn1/oiw/ElGamalParameter.cs
index b0a0ce348..4f1a8890c 100644
--- a/crypto/src/asn1/oiw/ElGamalParameter.cs
+++ b/crypto/src/asn1/oiw/ElGamalParameter.cs
@@ -7,39 +7,54 @@ namespace Org.BouncyCastle.Asn1.Oiw
     public class ElGamalParameter
         : Asn1Encodable
     {
-        internal DerInteger p, g;
-
-		public ElGamalParameter(
-            BigInteger	p,
-            BigInteger	g)
+        public static ElGamalParameter GetInstance(object obj)
         {
-            this.p = new DerInteger(p);
-            this.g = new DerInteger(g);
+            if (obj == null)
+                return null;
+            if (obj is ElGamalParameter elGamalParameter)
+                return elGamalParameter;
+#pragma warning disable CS0618 // Type or member is obsolete
+            return new ElGamalParameter(Asn1Sequence.GetInstance(obj));
+#pragma warning restore CS0618 // Type or member is obsolete
         }
 
-		public ElGamalParameter(
-            Asn1Sequence seq)
+        public static ElGamalParameter GetInstance(Asn1TaggedObject taggedObject, bool declaredExplicit)
         {
-			if (seq.Count != 2)
-				throw new ArgumentException("Wrong number of elements in sequence", "seq");
+#pragma warning disable CS0618 // Type or member is obsolete
+            return new ElGamalParameter(Asn1Sequence.GetInstance(taggedObject, declaredExplicit));
+#pragma warning restore CS0618 // Type or member is obsolete
+        }
 
-			p = DerInteger.GetInstance(seq[0]);
-			g = DerInteger.GetInstance(seq[1]);
+        public static ElGamalParameter GetTagged(Asn1TaggedObject taggedObject, bool declaredExplicit)
+        {
+#pragma warning disable CS0618 // Type or member is obsolete
+            return new ElGamalParameter(Asn1Sequence.GetTagged(taggedObject, declaredExplicit));
+#pragma warning restore CS0618 // Type or member is obsolete
         }
 
-		public BigInteger P
-		{
-			get { return p.PositiveValue; }
-		}
+        private readonly DerInteger m_p, m_g;
 
-		public BigInteger G
-		{
-			get { return g.PositiveValue; }
-		}
+        [Obsolete("Use 'GetInstance' instead")]
+        public ElGamalParameter(Asn1Sequence seq)
+        {
+            int count = seq.Count;
+            if (count != 2)
+                throw new ArgumentException("Bad sequence size: " + count, nameof(seq));
 
-		public override Asn1Object ToAsn1Object()
+			m_p = DerInteger.GetInstance(seq[0]);
+			m_g = DerInteger.GetInstance(seq[1]);
+        }
+
+        public ElGamalParameter(BigInteger p, BigInteger g)
         {
-			return new DerSequence(p, g);
+            m_p = new DerInteger(p);
+            m_g = new DerInteger(g);
         }
+
+        public BigInteger P => m_p.PositiveValue;
+
+		public BigInteger G => m_g.PositiveValue;
+
+		public override Asn1Object ToAsn1Object() => new DerSequence(m_p, m_g);
     }
 }
diff --git a/crypto/src/security/PrivateKeyFactory.cs b/crypto/src/security/PrivateKeyFactory.cs
index cf47eb272..670cebd7f 100644
--- a/crypto/src/security/PrivateKeyFactory.cs
+++ b/crypto/src/security/PrivateKeyFactory.cs
@@ -78,8 +78,7 @@ namespace Org.BouncyCastle.Security
             }
             else if (algOid.Equals(OiwObjectIdentifiers.ElGamalAlgorithm))
             {
-                ElGamalParameter para = new ElGamalParameter(
-                    Asn1Sequence.GetInstance(algID.Parameters.ToAsn1Object()));
+                ElGamalParameter para = ElGamalParameter.GetInstance(algID.Parameters);
                 DerInteger derX = (DerInteger)keyInfo.ParsePrivateKey();
 
                 return new ElGamalPrivateKeyParameters(
diff --git a/crypto/src/security/PublicKeyFactory.cs b/crypto/src/security/PublicKeyFactory.cs
index 234847870..933af4841 100644
--- a/crypto/src/security/PublicKeyFactory.cs
+++ b/crypto/src/security/PublicKeyFactory.cs
@@ -102,8 +102,7 @@ namespace Org.BouncyCastle.Security
             }
             else if (algOid.Equals(OiwObjectIdentifiers.ElGamalAlgorithm))
             {
-                ElGamalParameter para = new ElGamalParameter(
-                    Asn1Sequence.GetInstance(algID.Parameters.ToAsn1Object()));
+                ElGamalParameter para = ElGamalParameter.GetInstance(algID.Parameters);
                 DerInteger derY = (DerInteger)keyInfo.ParsePublicKey();
 
                 return new ElGamalPublicKeyParameters(
diff --git a/crypto/test/src/test/ElGamalTest.cs b/crypto/test/src/test/ElGamalTest.cs
index 293c0c37e..54e26a192 100644
--- a/crypto/test/src/test/ElGamalTest.cs
+++ b/crypto/test/src/test/ElGamalTest.cs
@@ -300,7 +300,7 @@ namespace Org.BouncyCastle.Tests
 
 //			AlgorithmParameters a2 = AlgorithmParameters.getInstance("ElGamal");
 //			a2.init(encodeParams);
-			ElGamalParameter elP = new ElGamalParameter((Asn1Sequence) Asn1Object.FromByteArray(encodeParams));
+			ElGamalParameter elP = ElGamalParameter.GetInstance(encodeParams);
 			ElGamalParameters p2 = new ElGamalParameters(elP.P, elP.G);
 
 			// a and a2 should be equivalent!
-- 
cgit 1.4.1