1 files changed, 153 insertions, 0 deletions
diff --git a/crypto/src/security/WrapperUtilities.cs b/crypto/src/security/WrapperUtilities.cs
new file mode 100644
index 000000000..ce31ea519
--- /dev/null
+++ b/crypto/src/security/WrapperUtilities.cs
@@ -0,0 +1,153 @@
+using System;
+using System.Collections;
+
+using Org.BouncyCastle.Asn1;
+using Org.BouncyCastle.Asn1.Kisa;
+using Org.BouncyCastle.Asn1.Nist;
+using Org.BouncyCastle.Asn1.Ntt;
+using Org.BouncyCastle.Asn1.Pkcs;
+using Org.BouncyCastle.Crypto;
+using Org.BouncyCastle.Crypto.Engines;
+using Org.BouncyCastle.Utilities;
+
+namespace Org.BouncyCastle.Security
+{
+    /// <remarks>
+    ///  Utility class for creating IWrapper objects from their names/Oids
+    /// </remarks>
+    public sealed class WrapperUtilities
+    {
+        private enum WrapAlgorithm { AESWRAP, CAMELLIAWRAP, DESEDEWRAP, RC2WRAP, SEEDWRAP,
+            DESEDERFC3211WRAP, AESRFC3211WRAP, CAMELLIARFC3211WRAP };
+
+        private WrapperUtilities()
+        {
+        }
+
+        private static readonly IDictionary algorithms = Platform.CreateHashtable();
+        //private static readonly IDictionary oids = Platform.CreateHashtable();
+
+        static WrapperUtilities()
+        {
+            // Signal to obfuscation tools not to change enum constants
+            ((WrapAlgorithm)Enums.GetArbitraryValue(typeof(WrapAlgorithm))).ToString();
+
+            algorithms[NistObjectIdentifiers.IdAes128Wrap.Id] = "AESWRAP";
+            algorithms[NistObjectIdentifiers.IdAes192Wrap.Id] = "AESWRAP";
+            algorithms[NistObjectIdentifiers.IdAes256Wrap.Id] = "AESWRAP";
+
+            algorithms[NttObjectIdentifiers.IdCamellia128Wrap.Id] = "CAMELLIAWRAP";
+            algorithms[NttObjectIdentifiers.IdCamellia192Wrap.Id] = "CAMELLIAWRAP";
+            algorithms[NttObjectIdentifiers.IdCamellia256Wrap.Id] = "CAMELLIAWRAP";
+
+            algorithms[PkcsObjectIdentifiers.IdAlgCms3DesWrap.Id] = "DESEDEWRAP";
+            algorithms["TDEAWRAP"] = "DESEDEWRAP";
+
+            algorithms[PkcsObjectIdentifiers.IdAlgCmsRC2Wrap.Id] = "RC2WRAP";
+
+            algorithms[KisaObjectIdentifiers.IdNpkiAppCmsSeedWrap.Id] = "SEEDWRAP";
+        }
+
+        public static IWrapper GetWrapper(
+            DerObjectIdentifier oid)
+        {
+            return GetWrapper(oid.Id);
+        }
+
+        public static IWrapper GetWrapper(
+            string algorithm)
+        {
+            string upper = Platform.ToUpperInvariant(algorithm);
+            string mechanism = (string)algorithms[upper];
+
+            if (mechanism == null)
+            {
+                mechanism = upper;
+            }
+
+            try
+            {
+                WrapAlgorithm wrapAlgorithm = (WrapAlgorithm)Enums.GetEnumValue(
+                    typeof(WrapAlgorithm), mechanism);
+
+                switch (wrapAlgorithm)
+                {
+                    case WrapAlgorithm.AESWRAP:				return new AesWrapEngine();
+                    case WrapAlgorithm.CAMELLIAWRAP:		return new CamelliaWrapEngine();
+                    case WrapAlgorithm.DESEDEWRAP:			return new DesEdeWrapEngine();
+                    case WrapAlgorithm.RC2WRAP:				return new RC2WrapEngine();
+                    case WrapAlgorithm.SEEDWRAP:			return new SeedWrapEngine();
+                    case WrapAlgorithm.DESEDERFC3211WRAP:	return new Rfc3211WrapEngine(new DesEdeEngine());
+                    case WrapAlgorithm.AESRFC3211WRAP:		return new Rfc3211WrapEngine(new AesFastEngine());
+                    case WrapAlgorithm.CAMELLIARFC3211WRAP:	return new Rfc3211WrapEngine(new CamelliaEngine());
+                }
+            }
+            catch (ArgumentException)
+            {
+            }
+
+            // Create an IBufferedCipher and use it as IWrapper (via BufferedCipherWrapper)
+            IBufferedCipher blockCipher = CipherUtilities.GetCipher(algorithm);
+
+            if (blockCipher != null)
+                return new BufferedCipherWrapper(blockCipher);
+
+            throw new SecurityUtilityException("Wrapper " + algorithm + " not recognised.");
+        }
+
+        public static string GetAlgorithmName(
+            DerObjectIdentifier oid)
+        {
+            return (string) algorithms[oid.Id];
+        }
+
+        private class BufferedCipherWrapper
+            : IWrapper
+        {
+            private readonly IBufferedCipher cipher;
+            private bool forWrapping;
+
+            public BufferedCipherWrapper(
+                IBufferedCipher cipher)
+            {
+                this.cipher = cipher;
+            }
+
+            public string AlgorithmName
+            {
+                get { return cipher.AlgorithmName; }
+            }
+
+            public void Init(
+                bool				forWrapping,
+                ICipherParameters	parameters)
+            {
+                this.forWrapping = forWrapping;
+
+                cipher.Init(forWrapping, parameters);
+            }
+
+            public byte[] Wrap(
+                byte[]	input,
+                int		inOff,
+                int		length)
+            {
+                if (!forWrapping)
+                    throw new InvalidOperationException("Not initialised for wrapping");
+
+                return cipher.DoFinal(input, inOff, length);
+            }
+
+            public byte[] Unwrap(
+                byte[]	input,
+                int		inOff,
+                int		length)
+            {
+                if (forWrapping)
+                    throw new InvalidOperationException("Not initialised for unwrapping");
+
+                return cipher.DoFinal(input, inOff, length);
+            }
+        }
+    }
+}