Rewrote NTLM support based on official specs.

Currently only NTLMv2 is implemented.

MailKit/MailKit.csproj

@@ -138,14 +138,17 @@
     <Compile Include="Search\UidSearchQuery.cs" />
     <Compile Include="Search\UnarySearchQuery.cs" />
     <Compile Include="Security\Ntlm\BitConverterLE.cs" />
-    <Compile Include="Security\Ntlm\ChallengeResponse2.cs" />
     <Compile Include="Security\Ntlm\DES.cs" Condition=" $(TargetFramework.StartsWith('netstandard1.')) " />
     <Compile Include="Security\Ntlm\HMACMD5.cs" Condition=" $(TargetFramework.StartsWith('netstandard1.')) " />
     <Compile Include="Security\Ntlm\MD4.cs" />
-    <Compile Include="Security\Ntlm\MessageBase.cs" />
-    <Compile Include="Security\Ntlm\NtlmAuthLevel.cs" />
+    <Compile Include="Security\Ntlm\NtlmAttribute.cs" />
+    <Compile Include="Security\Ntlm\NtlmAttributeValuePair.cs" />
     <Compile Include="Security\Ntlm\NtlmFlags.cs" />
-    <Compile Include="Security\Ntlm\TargetInfo.cs" />
+    <Compile Include="Security\Ntlm\NtlmMessageBase.cs" />
+    <Compile Include="Security\Ntlm\NtlmSingleHostData.cs" />
+    <Compile Include="Security\Ntlm\NtlmTargetInfo.cs" />
+    <Compile Include="Security\Ntlm\NtlmUtils.cs" />
+    <Compile Include="Security\Ntlm\RC4.cs" />
     <Compile Include="Security\Ntlm\Type1Message.cs" />
     <Compile Include="Security\Ntlm\Type2Message.cs" />
     <Compile Include="Security\Ntlm\Type3Message.cs" />

MailKit/Security/Ntlm/BitConverterLE.cs

@@ -26,14 +26,9 @@
 
 using System;
 
-namespace MailKit.Security.Ntlm
-{
-	sealed class BitConverterLE
+namespace MailKit.Security.Ntlm {
+	static class BitConverterLE
 	{
-		BitConverterLE ()
-		{
-		}
-
 		unsafe static byte[] GetULongBytes (byte *bytes)
 		{
 			if (BitConverter.IsLittleEndian)
@@ -73,7 +68,7 @@ unsafe static void UIntFromBytes (byte *dst, byte[] src, int startIndex)
 			}
 		}
 
-		unsafe internal static short ToInt16 (byte[] value, int startIndex)
+		public unsafe static short ToInt16 (byte[] value, int startIndex)
 		{
 			short ret;
 
@@ -82,7 +77,7 @@ unsafe internal static short ToInt16 (byte[] value, int startIndex)
 			return ret;
 		}
 
-		unsafe internal static int ToInt32 (byte[] value, int startIndex)
+		public unsafe static int ToInt32 (byte[] value, int startIndex)
 		{
 			int ret;
 
@@ -91,7 +86,7 @@ unsafe internal static int ToInt32 (byte[] value, int startIndex)
 			return ret;
 		}
 
-		unsafe internal static ushort ToUInt16 (byte[] value, int startIndex)
+		public unsafe static ushort ToUInt16 (byte[] value, int startIndex)
 		{
 			ushort ret;
 
@@ -100,7 +95,7 @@ unsafe internal static ushort ToUInt16 (byte[] value, int startIndex)
 			return ret;
 		}
 
-		unsafe internal static uint ToUInt32 (byte[] value, int startIndex)
+		public unsafe static uint ToUInt32 (byte[] value, int startIndex)
 		{
 			uint ret;