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-rw-r--r--crypto/src/security/GeneratorUtilities.cs646
1 files changed, 327 insertions, 319 deletions
diff --git a/crypto/src/security/GeneratorUtilities.cs b/crypto/src/security/GeneratorUtilities.cs
index 8e9290222..45fbc9425 100644
--- a/crypto/src/security/GeneratorUtilities.cs
+++ b/crypto/src/security/GeneratorUtilities.cs
@@ -1,5 +1,4 @@
 using System.Collections;
-using System.Globalization;
 
 using Org.BouncyCastle.Asn1;
 using Org.BouncyCastle.Asn1.CryptoPro;
@@ -17,325 +16,334 @@ using Org.BouncyCastle.Utilities.Collections;
 
 namespace Org.BouncyCastle.Security
 {
-	public sealed class GeneratorUtilities
-	{
-		private GeneratorUtilities()
-		{
-		}
+    public sealed class GeneratorUtilities
+    {
+        private GeneratorUtilities()
+        {
+        }
 
-		private static readonly IDictionary kgAlgorithms = Platform.CreateHashtable();
+        private static readonly IDictionary kgAlgorithms = Platform.CreateHashtable();
         private static readonly IDictionary kpgAlgorithms = Platform.CreateHashtable();
-		private static readonly IDictionary defaultKeySizes = Platform.CreateHashtable();
-
-		static GeneratorUtilities()
-		{
-			//
-			// key generators.
-			//
-			AddKgAlgorithm("AES",
-				"AESWRAP");
-			AddKgAlgorithm("AES128",
-				"2.16.840.1.101.3.4.2",
-				NistObjectIdentifiers.IdAes128Cbc,
-				NistObjectIdentifiers.IdAes128Cfb,
-				NistObjectIdentifiers.IdAes128Ecb,
-				NistObjectIdentifiers.IdAes128Ofb,
-				NistObjectIdentifiers.IdAes128Wrap);
-			AddKgAlgorithm("AES192",
-				"2.16.840.1.101.3.4.22",
-				NistObjectIdentifiers.IdAes192Cbc,
-				NistObjectIdentifiers.IdAes192Cfb,
-				NistObjectIdentifiers.IdAes192Ecb,
-				NistObjectIdentifiers.IdAes192Ofb,
-				NistObjectIdentifiers.IdAes192Wrap);
-			AddKgAlgorithm("AES256",
-				"2.16.840.1.101.3.4.42",
-				NistObjectIdentifiers.IdAes256Cbc,
-				NistObjectIdentifiers.IdAes256Cfb,
-				NistObjectIdentifiers.IdAes256Ecb,
-				NistObjectIdentifiers.IdAes256Ofb,
-				NistObjectIdentifiers.IdAes256Wrap);
-			AddKgAlgorithm("BLOWFISH",
-				"1.3.6.1.4.1.3029.1.2");
-			AddKgAlgorithm("CAMELLIA",
-				"CAMELLIAWRAP");
-			AddKgAlgorithm("CAMELLIA128",
-				NttObjectIdentifiers.IdCamellia128Cbc,
-				NttObjectIdentifiers.IdCamellia128Wrap);
-			AddKgAlgorithm("CAMELLIA192",
-				NttObjectIdentifiers.IdCamellia192Cbc,
-				NttObjectIdentifiers.IdCamellia192Wrap);
-			AddKgAlgorithm("CAMELLIA256",
-				NttObjectIdentifiers.IdCamellia256Cbc,
-				NttObjectIdentifiers.IdCamellia256Wrap);
-			AddKgAlgorithm("CAST5",
-				"1.2.840.113533.7.66.10");
-			AddKgAlgorithm("CAST6");
-			AddKgAlgorithm("DES",
-				OiwObjectIdentifiers.DesCbc,
-				OiwObjectIdentifiers.DesCfb,
-				OiwObjectIdentifiers.DesEcb,
-				OiwObjectIdentifiers.DesOfb);
-			AddKgAlgorithm("DESEDE",
-				"DESEDEWRAP",
-				OiwObjectIdentifiers.DesEde);
-			AddKgAlgorithm("DESEDE3",
-				PkcsObjectIdentifiers.DesEde3Cbc,
-				PkcsObjectIdentifiers.IdAlgCms3DesWrap);
-			AddKgAlgorithm("GOST28147",
-				"GOST",
-				"GOST-28147",
-				CryptoProObjectIdentifiers.GostR28147Cbc);
-			AddKgAlgorithm("HC128");
-			AddKgAlgorithm("HC256");
-			AddKgAlgorithm("IDEA",
-				"1.3.6.1.4.1.188.7.1.1.2");
-			AddKgAlgorithm("NOEKEON");
-			AddKgAlgorithm("RC2",
-				PkcsObjectIdentifiers.RC2Cbc,
-				PkcsObjectIdentifiers.IdAlgCmsRC2Wrap);
-			AddKgAlgorithm("RC4",
-				"ARC4",
-				"1.2.840.113549.3.4");
-			AddKgAlgorithm("RC5",
-				"RC5-32");
-			AddKgAlgorithm("RC5-64");
-			AddKgAlgorithm("RC6");
-			AddKgAlgorithm("RIJNDAEL");
-			AddKgAlgorithm("SALSA20");
-			AddKgAlgorithm("SEED",
-				KisaObjectIdentifiers.IdNpkiAppCmsSeedWrap,
-				KisaObjectIdentifiers.IdSeedCbc);
-			AddKgAlgorithm("SERPENT");
-			AddKgAlgorithm("SKIPJACK");
-			AddKgAlgorithm("TEA");
-			AddKgAlgorithm("TWOFISH");
-			AddKgAlgorithm("VMPC");
-			AddKgAlgorithm("VMPC-KSA3");
-			AddKgAlgorithm("XTEA");
-
-			//
-			// HMac key generators
-			//
-			AddHMacKeyGenerator("MD2");
-			AddHMacKeyGenerator("MD4");
-			AddHMacKeyGenerator("MD5",
-				IanaObjectIdentifiers.HmacMD5);
-			AddHMacKeyGenerator("SHA1",
-				PkcsObjectIdentifiers.IdHmacWithSha1,
-				IanaObjectIdentifiers.HmacSha1);
-			AddHMacKeyGenerator("SHA224",
-				PkcsObjectIdentifiers.IdHmacWithSha224);
-			AddHMacKeyGenerator("SHA256",
-				PkcsObjectIdentifiers.IdHmacWithSha256);
-			AddHMacKeyGenerator("SHA384",
-				PkcsObjectIdentifiers.IdHmacWithSha384);
-			AddHMacKeyGenerator("SHA512",
-				PkcsObjectIdentifiers.IdHmacWithSha512);
-			AddHMacKeyGenerator("RIPEMD128");
-			AddHMacKeyGenerator("RIPEMD160",
-				IanaObjectIdentifiers.HmacRipeMD160);
-			AddHMacKeyGenerator("TIGER",
-				IanaObjectIdentifiers.HmacTiger);
-
-
-
-			//
-			// key pair generators.
-			//
-			AddKpgAlgorithm("DH",
-				"DIFFIEHELLMAN");
-			AddKpgAlgorithm("DSA");
-			AddKpgAlgorithm("EC",
-				// TODO Should this be an alias for ECDH?
-				X9ObjectIdentifiers.DHSinglePassStdDHSha1KdfScheme);
-			AddKpgAlgorithm("ECDH",
-				"ECIES");
-			AddKpgAlgorithm("ECDHC");
-			AddKpgAlgorithm("ECMQV",
-				X9ObjectIdentifiers.MqvSinglePassSha1KdfScheme);
-			AddKpgAlgorithm("ECDSA");
-			AddKpgAlgorithm("ECGOST3410",
-				"ECGOST-3410",
-				"GOST-3410-2001");
-			AddKpgAlgorithm("ELGAMAL");
-			AddKpgAlgorithm("GOST3410",
+        private static readonly IDictionary defaultKeySizes = Platform.CreateHashtable();
+
+        static GeneratorUtilities()
+        {
+            //
+            // key generators.
+            //
+            AddKgAlgorithm("AES",
+                "AESWRAP");
+            AddKgAlgorithm("AES128",
+                "2.16.840.1.101.3.4.2",
+                NistObjectIdentifiers.IdAes128Cbc,
+                NistObjectIdentifiers.IdAes128Cfb,
+                NistObjectIdentifiers.IdAes128Ecb,
+                NistObjectIdentifiers.IdAes128Ofb,
+                NistObjectIdentifiers.IdAes128Wrap);
+            AddKgAlgorithm("AES192",
+                "2.16.840.1.101.3.4.22",
+                NistObjectIdentifiers.IdAes192Cbc,
+                NistObjectIdentifiers.IdAes192Cfb,
+                NistObjectIdentifiers.IdAes192Ecb,
+                NistObjectIdentifiers.IdAes192Ofb,
+                NistObjectIdentifiers.IdAes192Wrap);
+            AddKgAlgorithm("AES256",
+                "2.16.840.1.101.3.4.42",
+                NistObjectIdentifiers.IdAes256Cbc,
+                NistObjectIdentifiers.IdAes256Cfb,
+                NistObjectIdentifiers.IdAes256Ecb,
+                NistObjectIdentifiers.IdAes256Ofb,
+                NistObjectIdentifiers.IdAes256Wrap);
+            AddKgAlgorithm("BLOWFISH",
+                "1.3.6.1.4.1.3029.1.2");
+            AddKgAlgorithm("CAMELLIA",
+                "CAMELLIAWRAP");
+            AddKgAlgorithm("CAMELLIA128",
+                NttObjectIdentifiers.IdCamellia128Cbc,
+                NttObjectIdentifiers.IdCamellia128Wrap);
+            AddKgAlgorithm("CAMELLIA192",
+                NttObjectIdentifiers.IdCamellia192Cbc,
+                NttObjectIdentifiers.IdCamellia192Wrap);
+            AddKgAlgorithm("CAMELLIA256",
+                NttObjectIdentifiers.IdCamellia256Cbc,
+                NttObjectIdentifiers.IdCamellia256Wrap);
+            AddKgAlgorithm("CAST5",
+                "1.2.840.113533.7.66.10");
+            AddKgAlgorithm("CAST6");
+            AddKgAlgorithm("DES",
+                OiwObjectIdentifiers.DesCbc,
+                OiwObjectIdentifiers.DesCfb,
+                OiwObjectIdentifiers.DesEcb,
+                OiwObjectIdentifiers.DesOfb);
+            AddKgAlgorithm("DESEDE",
+                "DESEDEWRAP",
+                "TDEA",
+                OiwObjectIdentifiers.DesEde);
+            AddKgAlgorithm("DESEDE3",
+                PkcsObjectIdentifiers.DesEde3Cbc,
+                PkcsObjectIdentifiers.IdAlgCms3DesWrap);
+            AddKgAlgorithm("GOST28147",
+                "GOST",
+                "GOST-28147",
+                CryptoProObjectIdentifiers.GostR28147Cbc);
+            AddKgAlgorithm("HC128");
+            AddKgAlgorithm("HC256");
+            AddKgAlgorithm("IDEA",
+                "1.3.6.1.4.1.188.7.1.1.2");
+            AddKgAlgorithm("NOEKEON");
+            AddKgAlgorithm("RC2",
+                PkcsObjectIdentifiers.RC2Cbc,
+                PkcsObjectIdentifiers.IdAlgCmsRC2Wrap);
+            AddKgAlgorithm("RC4",
+                "ARC4",
+                "1.2.840.113549.3.4");
+            AddKgAlgorithm("RC5",
+                "RC5-32");
+            AddKgAlgorithm("RC5-64");
+            AddKgAlgorithm("RC6");
+            AddKgAlgorithm("RIJNDAEL");
+            AddKgAlgorithm("SALSA20");
+            AddKgAlgorithm("SEED",
+                KisaObjectIdentifiers.IdNpkiAppCmsSeedWrap,
+                KisaObjectIdentifiers.IdSeedCbc);
+            AddKgAlgorithm("SERPENT");
+            AddKgAlgorithm("SKIPJACK");
+            AddKgAlgorithm("TEA");
+            AddKgAlgorithm("TWOFISH");
+            AddKgAlgorithm("VMPC");
+            AddKgAlgorithm("VMPC-KSA3");
+            AddKgAlgorithm("XTEA");
+
+            //
+            // HMac key generators
+            //
+            AddHMacKeyGenerator("MD2");
+            AddHMacKeyGenerator("MD4");
+            AddHMacKeyGenerator("MD5",
+                IanaObjectIdentifiers.HmacMD5);
+            AddHMacKeyGenerator("SHA1",
+                PkcsObjectIdentifiers.IdHmacWithSha1,
+                IanaObjectIdentifiers.HmacSha1);
+            AddHMacKeyGenerator("SHA224",
+                PkcsObjectIdentifiers.IdHmacWithSha224);
+            AddHMacKeyGenerator("SHA256",
+                PkcsObjectIdentifiers.IdHmacWithSha256);
+            AddHMacKeyGenerator("SHA384",
+                PkcsObjectIdentifiers.IdHmacWithSha384);
+            AddHMacKeyGenerator("SHA512",
+                PkcsObjectIdentifiers.IdHmacWithSha512);
+            AddHMacKeyGenerator("SHA512/224");
+            AddHMacKeyGenerator("SHA512/256");
+            AddHMacKeyGenerator("SHA3-224");
+            AddHMacKeyGenerator("SHA3-256");
+            AddHMacKeyGenerator("SHA3-384");
+            AddHMacKeyGenerator("SHA3-512");
+            AddHMacKeyGenerator("RIPEMD128");
+            AddHMacKeyGenerator("RIPEMD160",
+                IanaObjectIdentifiers.HmacRipeMD160);
+            AddHMacKeyGenerator("TIGER",
+                IanaObjectIdentifiers.HmacTiger);
+
+
+
+            //
+            // key pair generators.
+            //
+            AddKpgAlgorithm("DH",
+                "DIFFIEHELLMAN");
+            AddKpgAlgorithm("DSA");
+            AddKpgAlgorithm("EC",
+                // TODO Should this be an alias for ECDH?
+                X9ObjectIdentifiers.DHSinglePassStdDHSha1KdfScheme);
+            AddKpgAlgorithm("ECDH",
+                "ECIES");
+            AddKpgAlgorithm("ECDHC");
+            AddKpgAlgorithm("ECMQV",
+                X9ObjectIdentifiers.MqvSinglePassSha1KdfScheme);
+            AddKpgAlgorithm("ECDSA");
+            AddKpgAlgorithm("ECGOST3410",
+                "ECGOST-3410",
+                "GOST-3410-2001");
+            AddKpgAlgorithm("ELGAMAL");
+            AddKpgAlgorithm("GOST3410",
                 "GOST-3410",
-				"GOST-3410-94");
-			AddKpgAlgorithm("RSA",
-				"1.2.840.113549.1.1.1");
-
-			AddDefaultKeySizeEntries(64, "DES");
-			AddDefaultKeySizeEntries(80, "SKIPJACK");
-			AddDefaultKeySizeEntries(128, "AES128", "BLOWFISH", "CAMELLIA128", "CAST5", "DESEDE",
-				"HC128", "HMACMD2", "HMACMD4", "HMACMD5", "HMACRIPEMD128", "IDEA", "NOEKEON",
-				"RC2", "RC4", "RC5", "SALSA20", "SEED", "TEA", "XTEA", "VMPC", "VMPC-KSA3");
-			AddDefaultKeySizeEntries(160, "HMACRIPEMD160", "HMACSHA1");
-			AddDefaultKeySizeEntries(192, "AES", "AES192", "CAMELLIA192", "DESEDE3", "HMACTIGER",
-				"RIJNDAEL", "SERPENT");
-			AddDefaultKeySizeEntries(224, "HMACSHA224");
-			AddDefaultKeySizeEntries(256, "AES256", "CAMELLIA", "CAMELLIA256", "CAST6", "GOST28147",
-				"HC256", "HMACSHA256", "RC5-64", "RC6", "TWOFISH");
-			AddDefaultKeySizeEntries(384, "HMACSHA384");
-			AddDefaultKeySizeEntries(512, "HMACSHA512");
-		}
-
-		private static void AddDefaultKeySizeEntries(int size, params string[] algorithms)
-		{
-			foreach (string algorithm in algorithms)
-			{
-				defaultKeySizes.Add(algorithm, size);
-			}
-		}
-
-		private static void AddKgAlgorithm(
-			string			canonicalName,
-			params object[] aliases)
-		{
-			kgAlgorithms[canonicalName] = canonicalName;
-
-			foreach (object alias in aliases)
-			{
-				kgAlgorithms[alias.ToString()] = canonicalName;
-			}
-		}
-
-		private static void AddKpgAlgorithm(
-			string			canonicalName,
-			params object[] aliases)
-		{
-			kpgAlgorithms[canonicalName] = canonicalName;
-
-			foreach (object alias in aliases)
-			{
-				kpgAlgorithms[alias.ToString()] = canonicalName;
-			}
-		}
-
-		private static void AddHMacKeyGenerator(
-			string			algorithm,
-			params object[]	aliases)
-		{
-			string mainName = "HMAC" + algorithm;
-
-			kgAlgorithms[mainName] = mainName;
-			kgAlgorithms["HMAC-" + algorithm] = mainName;
-			kgAlgorithms["HMAC/" + algorithm] = mainName;
-
-			foreach (object alias in aliases)
-			{
-				kgAlgorithms[alias.ToString()] = mainName;
-			}
-		}
-
-		// TODO Consider making this public
-		internal static string GetCanonicalKeyGeneratorAlgorithm(
-			string algorithm)
-		{
-			return (string) kgAlgorithms[algorithm.ToUpperInvariant()];
-		}
-
-		// TODO Consider making this public
-		internal static string GetCanonicalKeyPairGeneratorAlgorithm(
-			string algorithm)
-		{
-			return (string) kpgAlgorithms[algorithm.ToUpperInvariant()];
-		}
-
-		public static CipherKeyGenerator GetKeyGenerator(
-			DerObjectIdentifier oid)
-		{
-			return GetKeyGenerator(oid.Id);
-		}
-
-		public static CipherKeyGenerator GetKeyGenerator(
-			string algorithm)
-		{
-			string canonicalName = GetCanonicalKeyGeneratorAlgorithm(algorithm);
-
-			if (canonicalName == null)
-				throw new SecurityUtilityException("KeyGenerator " + algorithm + " not recognised.");
-
-			int defaultKeySize = FindDefaultKeySize(canonicalName);
-			if (defaultKeySize == -1)
-				throw new SecurityUtilityException("KeyGenerator " + algorithm
-					+ " (" + canonicalName + ") not supported.");
-
-			if (canonicalName == "DES")
-				return new DesKeyGenerator(defaultKeySize);
-
-			if (canonicalName == "DESEDE" || canonicalName == "DESEDE3")
-				return new DesEdeKeyGenerator(defaultKeySize);
-
-			return new CipherKeyGenerator(defaultKeySize);
-		}
-
-		public static IAsymmetricCipherKeyPairGenerator GetKeyPairGenerator(
-			DerObjectIdentifier oid)
-		{
-			return GetKeyPairGenerator(oid.Id);
-		}
-
-		public static IAsymmetricCipherKeyPairGenerator GetKeyPairGenerator(
-			string algorithm)
-		{
-			string canonicalName = GetCanonicalKeyPairGeneratorAlgorithm(algorithm);
-
-			if (canonicalName == null)
-				throw new SecurityUtilityException("KeyPairGenerator " + algorithm + " not recognised.");
-
-			if (canonicalName == "DH")
-				return new DHKeyPairGenerator();
-
-			if (canonicalName == "DSA")
-				return new DsaKeyPairGenerator();
-
-			// "EC", "ECDH", "ECDHC", "ECDSA", "ECGOST3410", "ECMQV"
-			if (canonicalName.StartsWith("EC"))
-				return new ECKeyPairGenerator(canonicalName);
-
-			if (canonicalName == "ELGAMAL")
-				return new ElGamalKeyPairGenerator();
-
-			if (canonicalName == "GOST3410")
-				return new Gost3410KeyPairGenerator();
-
-			if (canonicalName == "RSA")
-				return new RsaKeyPairGenerator();
-
-			throw new SecurityUtilityException("KeyPairGenerator " + algorithm
-				+ " (" + canonicalName + ") not supported.");
-		}
-
-		internal static int GetDefaultKeySize(
-			DerObjectIdentifier oid)
-		{
-			return GetDefaultKeySize(oid.Id);
-		}
-
-		internal static int GetDefaultKeySize(
-			string algorithm)
-		{
-			string canonicalName = GetCanonicalKeyGeneratorAlgorithm(algorithm);
-
-			if (canonicalName == null)
-				throw new SecurityUtilityException("KeyGenerator " + algorithm + " not recognised.");
-
-			int defaultKeySize = FindDefaultKeySize(canonicalName);
-			if (defaultKeySize == -1)
-				throw new SecurityUtilityException("KeyGenerator " + algorithm
-					+ " (" + canonicalName + ") not supported.");
-
-			return defaultKeySize;
-		}
-
-		private static int FindDefaultKeySize(
-			string canonicalName)
-		{
-			if (!defaultKeySizes.Contains(canonicalName))
-				return -1;
-
-			return (int)defaultKeySizes[canonicalName];
-		}
-	}
+                "GOST-3410-94");
+            AddKpgAlgorithm("RSA",
+                "1.2.840.113549.1.1.1");
+
+            AddDefaultKeySizeEntries(64, "DES");
+            AddDefaultKeySizeEntries(80, "SKIPJACK");
+            AddDefaultKeySizeEntries(128, "AES128", "BLOWFISH", "CAMELLIA128", "CAST5", "DESEDE",
+                "HC128", "HMACMD2", "HMACMD4", "HMACMD5", "HMACRIPEMD128", "IDEA", "NOEKEON",
+                "RC2", "RC4", "RC5", "SALSA20", "SEED", "TEA", "XTEA", "VMPC", "VMPC-KSA3");
+            AddDefaultKeySizeEntries(160, "HMACRIPEMD160", "HMACSHA1");
+            AddDefaultKeySizeEntries(192, "AES", "AES192", "CAMELLIA192", "DESEDE3", "HMACTIGER",
+                "RIJNDAEL", "SERPENT");
+            AddDefaultKeySizeEntries(224, "HMACSHA224");
+            AddDefaultKeySizeEntries(256, "AES256", "CAMELLIA", "CAMELLIA256", "CAST6", "GOST28147",
+                "HC256", "HMACSHA256", "RC5-64", "RC6", "TWOFISH");
+            AddDefaultKeySizeEntries(384, "HMACSHA384");
+            AddDefaultKeySizeEntries(512, "HMACSHA512");
+            AddDefaultKeySizeEntries(224, "HMACSHA512/224");
+            AddDefaultKeySizeEntries(256, "HMACSHA512/256");
+        }
+
+        private static void AddDefaultKeySizeEntries(int size, params string[] algorithms)
+        {
+            foreach (string algorithm in algorithms)
+            {
+                defaultKeySizes.Add(algorithm, size);
+            }
+        }
+
+        private static void AddKgAlgorithm(
+            string			canonicalName,
+            params object[] aliases)
+        {
+            kgAlgorithms[canonicalName] = canonicalName;
+
+            foreach (object alias in aliases)
+            {
+                kgAlgorithms[alias.ToString()] = canonicalName;
+            }
+        }
+
+        private static void AddKpgAlgorithm(
+            string			canonicalName,
+            params object[] aliases)
+        {
+            kpgAlgorithms[canonicalName] = canonicalName;
+
+            foreach (object alias in aliases)
+            {
+                kpgAlgorithms[alias.ToString()] = canonicalName;
+            }
+        }
+
+        private static void AddHMacKeyGenerator(
+            string			algorithm,
+            params object[]	aliases)
+        {
+            string mainName = "HMAC" + algorithm;
+
+            kgAlgorithms[mainName] = mainName;
+            kgAlgorithms["HMAC-" + algorithm] = mainName;
+            kgAlgorithms["HMAC/" + algorithm] = mainName;
+
+            foreach (object alias in aliases)
+            {
+                kgAlgorithms[alias.ToString()] = mainName;
+            }
+        }
+
+        // TODO Consider making this public
+        internal static string GetCanonicalKeyGeneratorAlgorithm(
+            string algorithm)
+        {
+            return (string) kgAlgorithms[Platform.ToUpperInvariant(algorithm)];
+        }
+
+        // TODO Consider making this public
+        internal static string GetCanonicalKeyPairGeneratorAlgorithm(
+            string algorithm)
+        {
+            return (string)kpgAlgorithms[Platform.ToUpperInvariant(algorithm)];
+        }
+
+        public static CipherKeyGenerator GetKeyGenerator(
+            DerObjectIdentifier oid)
+        {
+            return GetKeyGenerator(oid.Id);
+        }
+
+        public static CipherKeyGenerator GetKeyGenerator(
+            string algorithm)
+        {
+            string canonicalName = GetCanonicalKeyGeneratorAlgorithm(algorithm);
+
+            if (canonicalName == null)
+                throw new SecurityUtilityException("KeyGenerator " + algorithm + " not recognised.");
+
+            int defaultKeySize = FindDefaultKeySize(canonicalName);
+            if (defaultKeySize == -1)
+                throw new SecurityUtilityException("KeyGenerator " + algorithm
+                    + " (" + canonicalName + ") not supported.");
+
+            if (canonicalName == "DES")
+                return new DesKeyGenerator(defaultKeySize);
+
+            if (canonicalName == "DESEDE" || canonicalName == "DESEDE3")
+                return new DesEdeKeyGenerator(defaultKeySize);
+
+            return new CipherKeyGenerator(defaultKeySize);
+        }
+
+        public static IAsymmetricCipherKeyPairGenerator GetKeyPairGenerator(
+            DerObjectIdentifier oid)
+        {
+            return GetKeyPairGenerator(oid.Id);
+        }
+
+        public static IAsymmetricCipherKeyPairGenerator GetKeyPairGenerator(
+            string algorithm)
+        {
+            string canonicalName = GetCanonicalKeyPairGeneratorAlgorithm(algorithm);
+
+            if (canonicalName == null)
+                throw new SecurityUtilityException("KeyPairGenerator " + algorithm + " not recognised.");
+
+            if (canonicalName == "DH")
+                return new DHKeyPairGenerator();
+
+            if (canonicalName == "DSA")
+                return new DsaKeyPairGenerator();
+
+            // "EC", "ECDH", "ECDHC", "ECDSA", "ECGOST3410", "ECMQV"
+            if (canonicalName.StartsWith("EC"))
+                return new ECKeyPairGenerator(canonicalName);
+
+            if (canonicalName == "ELGAMAL")
+                return new ElGamalKeyPairGenerator();
+
+            if (canonicalName == "GOST3410")
+                return new Gost3410KeyPairGenerator();
+
+            if (canonicalName == "RSA")
+                return new RsaKeyPairGenerator();
+
+            throw new SecurityUtilityException("KeyPairGenerator " + algorithm
+                + " (" + canonicalName + ") not supported.");
+        }
+
+        internal static int GetDefaultKeySize(
+            DerObjectIdentifier oid)
+        {
+            return GetDefaultKeySize(oid.Id);
+        }
+
+        internal static int GetDefaultKeySize(
+            string algorithm)
+        {
+            string canonicalName = GetCanonicalKeyGeneratorAlgorithm(algorithm);
+
+            if (canonicalName == null)
+                throw new SecurityUtilityException("KeyGenerator " + algorithm + " not recognised.");
+
+            int defaultKeySize = FindDefaultKeySize(canonicalName);
+            if (defaultKeySize == -1)
+                throw new SecurityUtilityException("KeyGenerator " + algorithm
+                    + " (" + canonicalName + ") not supported.");
+
+            return defaultKeySize;
+        }
+
+        private static int FindDefaultKeySize(
+            string canonicalName)
+        {
+            if (!defaultKeySizes.Contains(canonicalName))
+                return -1;
+
+            return (int)defaultKeySizes[canonicalName];
+        }
+    }
 }