RFC 7250 Add methods to work with required extension types

4 files changed, 125 insertions, 43 deletions

diff --git a/crypto/src/crypto/tls/TlsDHUtilities.cs b/crypto/src/crypto/tls/TlsDHUtilities.cs
index 7a44670fd..6df61cbed 100644
--- a/crypto/src/crypto/tls/TlsDHUtilities.cs
+++ b/crypto/src/crypto/tls/TlsDHUtilities.cs
@@ -204,36 +204,20 @@ namespace Org.BouncyCastle.Crypto.Tls
 
         public static byte[] CreateNegotiatedDheGroupsServerExtension(byte dheGroup)
         {
-            return new byte[]{ dheGroup };
+            return TlsUtilities.EncodeUint8(dheGroup);
         }
 
         public static byte[] ReadNegotiatedDheGroupsClientExtension(byte[] extensionData)
         {
-            if (extensionData == null)
-                throw new ArgumentNullException("extensionData");
-
-            MemoryStream buf = new MemoryStream(extensionData, false);
-
-            byte length = TlsUtilities.ReadUint8(buf);
-            if (length < 1)
+            byte[] dheGroups = TlsUtilities.DecodeUint8ArrayWithUint8Length(extensionData);
+            if (dheGroups.Length < 1)
                 throw new TlsFatalAlert(AlertDescription.decode_error);
-
-            byte[] dheGroups = TlsUtilities.ReadUint8Array(length, buf);
-
-            TlsProtocol.AssertEmpty(buf);
-
             return dheGroups;
         }
 
         public static byte ReadNegotiatedDheGroupsServerExtension(byte[] extensionData)
         {
-            if (extensionData == null)
-                throw new ArgumentNullException("extensionData");
-
-            if (extensionData.Length != 1)
-                throw new TlsFatalAlert(AlertDescription.decode_error);
-
-            return extensionData[0];
+            return TlsUtilities.DecodeUint8(extensionData);
         }
 
         public static DHParameters GetParametersForDHEGroup(short dheGroup)
diff --git a/crypto/src/crypto/tls/TlsEccUtilities.cs b/crypto/src/crypto/tls/TlsEccUtilities.cs
index a5c8fa910..fb31e1b07 100644
--- a/crypto/src/crypto/tls/TlsEccUtilities.cs
+++ b/crypto/src/crypto/tls/TlsEccUtilities.cs
@@ -90,19 +90,7 @@ namespace Org.BouncyCastle.Crypto.Tls
 
         public static byte[] ReadSupportedPointFormatsExtension(byte[] extensionData)
         {
-            if (extensionData == null)
-                throw new ArgumentNullException("extensionData");
-
-            MemoryStream buf = new MemoryStream(extensionData, false);
-
-            byte length = TlsUtilities.ReadUint8(buf);
-            if (length < 1)
-                throw new TlsFatalAlert(AlertDescription.decode_error);
-
-            byte[] ecPointFormats = TlsUtilities.ReadUint8Array(length, buf);
-
-            TlsProtocol.AssertEmpty(buf);
-
+            byte[] ecPointFormats = TlsUtilities.DecodeUint8ArrayWithUint8Length(extensionData);
             if (!Arrays.Contains(ecPointFormats, ECPointFormat.uncompressed))
             {
                 /*
@@ -111,7 +99,6 @@ namespace Org.BouncyCastle.Crypto.Tls
                  */
                 throw new TlsFatalAlert(AlertDescription.illegal_parameter);
             }
-
             return ecPointFormats;
         }
 
diff --git a/crypto/src/crypto/tls/TlsExtensionsUtilities.cs b/crypto/src/crypto/tls/TlsExtensionsUtilities.cs
index 7f6a26ef2..4b3d9e0c5 100644
--- a/crypto/src/crypto/tls/TlsExtensionsUtilities.cs
+++ b/crypto/src/crypto/tls/TlsExtensionsUtilities.cs
@@ -13,6 +13,18 @@ namespace Org.BouncyCastle.Crypto.Tls
             return extensions == null ? Platform.CreateHashtable() : extensions;
         }
 
+        /// <exception cref="IOException"></exception>
+        public static void AddClientCertificateTypeExtensionClient(IDictionary extensions, byte[] certificateTypes)
+        {
+            extensions[ExtensionType.client_certificate_type] = CreateCertificateTypeExtensionClient(certificateTypes);
+        }
+
+        /// <exception cref="IOException"></exception>
+        public static void AddClientCertificateTypeExtensionServer(IDictionary extensions, byte certificateType)
+        {
+            extensions[ExtensionType.client_certificate_type] = CreateCertificateTypeExtensionServer(certificateType);
+        }
+
         public static void AddEncryptThenMacExtension(IDictionary extensions)
         {
             extensions[ExtensionType.encrypt_then_mac] = CreateEncryptThenMacExtension();
@@ -42,6 +54,18 @@ namespace Org.BouncyCastle.Crypto.Tls
         }
 
         /// <exception cref="IOException"></exception>
+        public static void AddServerCertificateTypeExtensionClient(IDictionary extensions, byte[] certificateTypes)
+        {
+            extensions[ExtensionType.server_certificate_type] = CreateCertificateTypeExtensionClient(certificateTypes);
+        }
+
+        /// <exception cref="IOException"></exception>
+        public static void AddServerCertificateTypeExtensionServer(IDictionary extensions, byte certificateType)
+        {
+            extensions[ExtensionType.server_certificate_type] = CreateCertificateTypeExtensionServer(certificateType);
+        }
+
+        /// <exception cref="IOException"></exception>
         public static void AddServerNameExtension(IDictionary extensions, ServerNameList serverNameList)
         {
             extensions[ExtensionType.server_name] = CreateServerNameExtension(serverNameList);
@@ -59,6 +83,20 @@ namespace Org.BouncyCastle.Crypto.Tls
         }
 
         /// <exception cref="IOException"></exception>
+        public static byte[] GetClientCertificateTypeExtensionClient(IDictionary extensions)
+        {
+            byte[] extensionData = TlsUtilities.GetExtensionData(extensions, ExtensionType.client_certificate_type);
+            return extensionData == null ? null : ReadCertificateTypeExtensionClient(extensionData);
+        }
+
+        /// <exception cref="IOException"></exception>
+        public static short GetClientCertificateTypeExtensionServer(IDictionary extensions)
+        {
+            byte[] extensionData = TlsUtilities.GetExtensionData(extensions, ExtensionType.client_certificate_type);
+            return extensionData == null ? (short)-1 : (short)ReadCertificateTypeExtensionServer(extensionData);
+        }
+
+        /// <exception cref="IOException"></exception>
         public static HeartbeatExtension GetHeartbeatExtension(IDictionary extensions)
         {
             byte[] extensionData = TlsUtilities.GetExtensionData(extensions, ExtensionType.heartbeat);
@@ -80,6 +118,20 @@ namespace Org.BouncyCastle.Crypto.Tls
         }
 
         /// <exception cref="IOException"></exception>
+        public static byte[] GetServerCertificateTypeExtensionClient(IDictionary extensions)
+        {
+            byte[] extensionData = TlsUtilities.GetExtensionData(extensions, ExtensionType.server_certificate_type);
+            return extensionData == null ? null : ReadCertificateTypeExtensionClient(extensionData);
+        }
+
+        /// <exception cref="IOException"></exception>
+        public static short GetServerCertificateTypeExtensionServer(IDictionary extensions)
+        {
+            byte[] extensionData = TlsUtilities.GetExtensionData(extensions, ExtensionType.server_certificate_type);
+            return extensionData == null ? (short)-1 : (short)ReadCertificateTypeExtensionServer(extensionData);
+        }
+
+        /// <exception cref="IOException"></exception>
         public static ServerNameList GetServerNameExtension(IDictionary extensions)
         {
             byte[] extensionData = TlsUtilities.GetExtensionData(extensions, ExtensionType.server_name);
@@ -114,6 +166,21 @@ namespace Org.BouncyCastle.Crypto.Tls
             return extensionData == null ? false : ReadTruncatedHMacExtension(extensionData);
         }
 
+        /// <exception cref="IOException"></exception>
+        public static byte[] CreateCertificateTypeExtensionClient(byte[] certificateTypes)
+        {
+            if (certificateTypes == null || certificateTypes.Length < 1 || certificateTypes.Length > 255)
+                throw new TlsFatalAlert(AlertDescription.internal_error);
+
+            return TlsUtilities.EncodeUint8ArrayWithUint8Length(certificateTypes);
+        }
+
+        /// <exception cref="IOException"></exception>
+        public static byte[] CreateCertificateTypeExtensionServer(byte certificateType)
+        {
+            return TlsUtilities.EncodeUint8(certificateType);
+        }
+
         public static byte[] CreateEmptyExtensionData()
         {
             return TlsUtilities.EmptyBytes;
@@ -145,7 +212,7 @@ namespace Org.BouncyCastle.Crypto.Tls
         /// <exception cref="IOException"></exception>
         public static byte[] CreateMaxFragmentLengthExtension(byte maxFragmentLength)
         {
-            return new byte[]{ maxFragmentLength };
+            return TlsUtilities.EncodeUint8(maxFragmentLength);
         }
 
         /// <exception cref="IOException"></exception>
@@ -201,6 +268,21 @@ namespace Org.BouncyCastle.Crypto.Tls
         }
 
         /// <exception cref="IOException"></exception>
+        public static byte[] ReadCertificateTypeExtensionClient(byte[] extensionData)
+        {
+            byte[] certificateTypes = TlsUtilities.DecodeUint8ArrayWithUint8Length(extensionData);
+            if (certificateTypes.Length < 1)
+                throw new TlsFatalAlert(AlertDescription.decode_error);
+            return certificateTypes;
+        }
+
+        /// <exception cref="IOException"></exception>
+        public static byte ReadCertificateTypeExtensionServer(byte[] extensionData)
+        {
+            return TlsUtilities.DecodeUint8(extensionData);
+        }
+
+        /// <exception cref="IOException"></exception>
         public static bool ReadEncryptThenMacExtension(byte[] extensionData)
         {
             return ReadEmptyExtensionData(extensionData);
@@ -228,15 +310,9 @@ namespace Org.BouncyCastle.Crypto.Tls
         }
 
         /// <exception cref="IOException"></exception>
-        public static short ReadMaxFragmentLengthExtension(byte[] extensionData)
+        public static byte ReadMaxFragmentLengthExtension(byte[] extensionData)
         {
-            if (extensionData == null)
-                throw new ArgumentNullException("extensionData");
-
-            if (extensionData.Length != 1)
-                throw new TlsFatalAlert(AlertDescription.decode_error);
-
-            return extensionData[0];
+            return TlsUtilities.DecodeUint8(extensionData);
         }
 
         /// <exception cref="IOException"></exception>
diff --git a/crypto/src/crypto/tls/TlsUtilities.cs b/crypto/src/crypto/tls/TlsUtilities.cs
index 48e51a7b6..48eb9d375 100644
--- a/crypto/src/crypto/tls/TlsUtilities.cs
+++ b/crypto/src/crypto/tls/TlsUtilities.cs
@@ -324,12 +324,47 @@ namespace Org.BouncyCastle.Crypto.Tls
             WriteUint16Array(uints, buf, offset + 2);
         }
 
+        public static byte DecodeUint8(byte[] buf)
+        {
+            if (buf == null)
+                throw new ArgumentNullException("buf");
+            if (buf.Length != 1)
+                throw new TlsFatalAlert(AlertDescription.decode_error);
+            return ReadUint8(buf, 0);
+        }
+
+        public static byte[] DecodeUint8ArrayWithUint8Length(byte[] buf)
+        {
+            if (buf == null)
+                throw new ArgumentNullException("buf");
+
+            int count = ReadUint8(buf, 0);
+            if (buf.Length != (count + 1))
+                throw new TlsFatalAlert(AlertDescription.decode_error);
+
+            byte[] uints = new byte[count];
+            for (int i = 0; i < count; ++i)
+            {
+                uints[i] = ReadUint8(buf, i + 1);
+            }
+            return uints;
+        }
+
         public static byte[] EncodeOpaque8(byte[] buf)
         {
             CheckUint8(buf.Length);
             return Arrays.Prepend(buf, (byte)buf.Length);
         }
 
+        public static byte[] EncodeUint8(byte val)
+        {
+            CheckUint8(val);
+
+            byte[] extensionData = new byte[1];
+            WriteUint8(val, extensionData, 0);
+            return extensionData;
+        }
+
         public static byte[] EncodeUint8ArrayWithUint8Length(byte[] uints)
         {
             byte[] result = new byte[1 + uints.Length];