Added SCRAM-SHA-256 support #51

XMPP_API/Classes/Network/XML/Messages/Features/SASL/SHA1/ScramSHA1SASLMechanism.cs

@@ -84,10 +84,15 @@ public override AbstractMessage generateResponse(AbstractMessage msg)
                     // Throw wrong order
                 }
                 itersStr = itersStr.Substring(2);
-                if (!int.TryParse(itersStr, out int iters))
+                int iters = -1;
+                if (!int.TryParse(itersStr, out iters))
                 {
                     // Throw could not pars iterations
                 }
+                else if (!isValidIterationsCount(iters))
+                {
+                    // Throw invalid iterations count
+                }
 
                 return new ScramSha1ChallengeSolutionMessage(computeAnswer(iters));
             }
@@ -106,7 +111,7 @@ public override SelectSASLMechanismMessage getSelectSASLMechanismMessage()
         #endregion
 
         #region --Misc Methods (Private)--
-        private string computeAnswer(int iterations)
+        protected string computeAnswer(int iterations)
         {
             string clientFinalMessageBare = "c=biws,r=" + serverNonce;
             byte[] saltBytes = Convert.FromBase64String(saltBase64);
@@ -123,6 +128,11 @@ private string computeAnswer(int iterations)
             return encodeStringBase64(clientFinalMessage);
         }
 
+        protected virtual bool isValidIterationsCount(int iters)
+        {
+            return iters > 0;
+        }
+
         #endregion
 
         #region --Misc Methods (Protected)--

XMPP_API/Classes/Network/XML/Messages/Features/SASL/SHA1/ScramSHA256SASLMechanism.cs

@@ -0,0 +1,69 @@
+namespace XMPP_API.Classes.Network.XML.Messages.Features.SASL.SHA1
+{
+    public class ScramSHA256SASLMechanism : ScramSHA1SASLMechanism
+    {
+        // https://tools.ietf.org/html/rfc7677
+        //--------------------------------------------------------Attributes:-----------------------------------------------------------------\\
+        #region --Attributes--
+        private const byte CLIENT_NONCE_LENGTH = 32;
+
+        private readonly string CLIENT_NONCE_BASE_64;
+        private readonly string PASSWORD_NORMALIZED;
+        private string serverNonce;
+        private string saltBase64;
+        private string clientFirstMsg;
+        private string serverFirstMsg;
+
+        #endregion
+        //--------------------------------------------------------Constructor:----------------------------------------------------------------\\
+        #region --Constructors--
+        /// <summary>
+        /// Basic Constructor
+        /// </summary>
+        /// <history>
+        /// 06/01/2019 Created [Fabian Sauter]
+        /// </history>
+        public ScramSHA256SASLMechanism(string id, string password) : base(id, password)
+        {
+        }
+
+        public ScramSHA256SASLMechanism(string id, string password, string clientNonceBase64) : base(id, password, clientNonceBase64)
+        {
+        }
+
+        #endregion
+        //--------------------------------------------------------Set-, Get- Methods:---------------------------------------------------------\\
+        #region --Set-, Get- Methods--
+
+
+        #endregion
+        //--------------------------------------------------------Misc Methods:---------------------------------------------------------------\\
+        #region --Misc Methods (Public)--
+        public override SelectSASLMechanismMessage getSelectSASLMechanismMessage()
+        {
+            clientFirstMsg = "n=" + ID + ",r=" + CLIENT_NONCE_BASE_64;
+            string encClientFirstMsg = encodeStringBase64("n,," + clientFirstMsg);
+
+            return new SelectSASLMechanismMessage("SCRAM-SHA-256", encClientFirstMsg);
+        }
+
+        #endregion
+
+        #region --Misc Methods (Private)--
+
+        #endregion
+
+        #region --Misc Methods (Protected)--
+        protected override bool isValidIterationsCount(int iters)
+        {
+            return iters >= 4096;
+        }
+
+        #endregion
+        //--------------------------------------------------------Events:---------------------------------------------------------------------\\
+        #region --Events--
+
+
+        #endregion
+    }
+}

XMPP_API/Classes/Network/XML/Messages/Processor/SASLConnection.cs

@@ -18,7 +18,7 @@ class SASLConnection : AbstractMessageProcessor
         private SASLState state;
         private AbstractSASLMechanism selectedMechanism;
         // The offered authentication mechanism in preferred order:
-        private static readonly ArrayList OFFERED_MECHANISMS = new ArrayList() { "scram-sha-1", "plain" };
+        private static readonly ArrayList OFFERED_MECHANISMS = new ArrayList() { "scram-sha-256", "scram-sha-1", "plain" };
 
         #endregion
         //--------------------------------------------------------Constructor:----------------------------------------------------------------\\
@@ -83,6 +83,10 @@ private void selectMechanism(ArrayList mechanisms)
             XMPPAccount sCC = XMPP_CONNECTION.account;
             switch (selected)
             {
+                case "scram-sha-256":
+                    selectedMechanism = new ScramSHA256SASLMechanism(sCC.user.userId, sCC.user.userPassword);
+                    break;
+
                 case "scram-sha-1":
                     selectedMechanism = new ScramSHA1SASLMechanism(sCC.user.userId, sCC.user.userPassword);
                     break;

XMPP_API/XMPP_API.csproj

@@ -159,6 +159,7 @@
     <Compile Include="Classes\Network\XML\Messages\BindResourceMessage.cs" />
     <Compile Include="Classes\Network\XML\Messages\Error.cs" />
     <Compile Include="Classes\Crypto\CryptoUtils.cs" />
+    <Compile Include="Classes\Network\XML\Messages\Features\SASL\SHA1\ScramSHA256SASLMechanism.cs" />
     <Compile Include="Classes\Network\XML\Messages\StreamErrorType.cs" />
     <Compile Include="Classes\Network\XML\Messages\StreamErrorMessage.cs" />
     <Compile Include="Classes\Network\XML\Messages\Features\SASL\SASLErrorType.cs" />