1 files changed, 108 insertions, 0 deletions
diff --git a/crypto/src/tls/ServerHello.cs b/crypto/src/tls/ServerHello.cs
new file mode 100644
index 000000000..15cc09032
--- /dev/null
+++ b/crypto/src/tls/ServerHello.cs
@@ -0,0 +1,108 @@
+using System;
+using System.Collections;
+using System.IO;
+
+using Org.BouncyCastle.Utilities;
+
+namespace Org.BouncyCastle.Tls
+{
+    public sealed class ServerHello
+    {
+        private static readonly byte[] HelloRetryRequestMagic = { 0xCF, 0x21, 0xAD, 0x74, 0xE5, 0x9A, 0x61, 0x11, 0xBE,
+            0x1D, 0x8C, 0x02, 0x1E, 0x65, 0xB8, 0x91, 0xC2, 0xA2, 0x11, 0x16, 0x7A, 0xBB, 0x8C, 0x5E, 0x07, 0x9E, 0x09,
+            0xE2, 0xC8, 0xA8, 0x33, 0x9C };
+
+        private readonly ProtocolVersion m_version;
+        private readonly byte[] m_random;
+        private readonly byte[] m_sessionID;
+        private readonly int m_cipherSuite;
+        private readonly IDictionary m_extensions;
+
+        public ServerHello(byte[] sessionID, int cipherSuite, IDictionary extensions)
+            : this(ProtocolVersion.TLSv12, Arrays.Clone(HelloRetryRequestMagic), sessionID, cipherSuite, extensions)
+        {
+        }
+
+        public ServerHello(ProtocolVersion version, byte[] random, byte[] sessionID, int cipherSuite,
+            IDictionary extensions)
+        {
+            this.m_version = version;
+            this.m_random = random;
+            this.m_sessionID = sessionID;
+            this.m_cipherSuite = cipherSuite;
+            this.m_extensions = extensions;
+        }
+
+        public int CipherSuite
+        {
+            get { return m_cipherSuite; }
+        }
+
+        public IDictionary Extensions
+        {
+            get { return m_extensions; }
+        }
+
+        public byte[] Random
+        {
+            get { return m_random; }
+        }
+
+        public byte[] SessionID
+        {
+            get { return m_sessionID; }
+        }
+
+        public ProtocolVersion Version
+        {
+            get { return m_version; }
+        }
+
+        public bool IsHelloRetryRequest()
+        {
+            return Arrays.AreEqual(HelloRetryRequestMagic, m_random);
+        }
+
+        /// <summary>Encode this <see cref="ServerHello"/> to a <see cref="Stream"/>.</summary>
+        /// <param name="context">the <see cref="TlsContext"/> of the current connection.</param>
+        /// <param name="output">the <see cref="Stream"/> to encode to.</param>
+        /// <exception cref="IOException"/>
+        public void Encode(TlsContext context, Stream output)
+        {
+            TlsUtilities.WriteVersion(m_version, output);
+
+            output.Write(m_random, 0, m_random.Length);
+
+            TlsUtilities.WriteOpaque8(m_sessionID, output);
+
+            TlsUtilities.WriteUint16(m_cipherSuite, output);
+
+            TlsUtilities.WriteUint8(CompressionMethod.cls_null, output);
+
+            TlsProtocol.WriteExtensions(output, m_extensions);
+        }
+
+        /// <summary>Parse a <see cref="ServerHello"/> from a <see cref="MemoryStream"/>.</summary>
+        /// <param name="input">the <see cref="MemoryStream"/> to parse from.</param>
+        /// <returns>a <see cref="ServerHello"/> object.</returns>
+        /// <exception cref="IOException"/>
+        public static ServerHello Parse(MemoryStream input)
+        {
+            ProtocolVersion version = TlsUtilities.ReadVersion(input);
+
+            byte[] random = TlsUtilities.ReadFully(32, input);
+
+            byte[] sessionID = TlsUtilities.ReadOpaque8(input, 0, 32);
+
+            int cipherSuite = TlsUtilities.ReadUint16(input);
+
+            short compressionMethod = TlsUtilities.ReadUint8(input);
+            if (CompressionMethod.cls_null != compressionMethod)
+                throw new TlsFatalAlert(AlertDescription.illegal_parameter);
+
+            IDictionary extensions = TlsProtocol.ReadExtensions(input);
+
+            return new ServerHello(version, random, sessionID, cipherSuite, extensions);
+        }
+    }
+}