1 files changed, 107 insertions, 0 deletions

diff --git a/OpenSim/Framework/Servers/HttpServer/BaseStreamHandlerBasicDOSProtector.cs b/OpenSim/Framework/Servers/HttpServer/BaseStreamHandlerBasicDOSProtector.cs
new file mode 100644
index 0000000..1b88545
--- /dev/null
+++ b/OpenSim/Framework/Servers/HttpServer/BaseStreamHandlerBasicDOSProtector.cs
@@ -0,0 +1,107 @@
+/*
+ * Copyright (c) Contributors, http://opensimulator.org/
+ * See CONTRIBUTORS.TXT for a full list of copyright holders.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *     * Neither the name of the OpenSimulator Project nor the
+ *       names of its contributors may be used to endorse or promote products
+ *       derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+using OpenSim.Framework;
+using System.IO;
+
+namespace OpenSim.Framework.Servers.HttpServer
+{
+    /// <summary>
+    /// BaseStreamHandlerBasicDOSProtector Base streamed request handler.
+    /// </summary>
+    /// <remarks>
+    /// Inheriting classes should override ProcessRequest() rather than Handle()
+    /// </remarks>
+    public abstract class BaseStreamHandlerBasicDOSProtector : BaseRequestHandler, IStreamedRequestHandler
+    {
+       
+        private readonly BasicDosProtectorOptions _options;
+        private readonly BasicDOSProtector _dosProtector;
+
+        protected BaseStreamHandlerBasicDOSProtector(string httpMethod, string path, BasicDosProtectorOptions options) : this(httpMethod, path, null, null, options) {}
+
+        protected BaseStreamHandlerBasicDOSProtector(string httpMethod, string path, string name, string description, BasicDosProtectorOptions options)
+            : base(httpMethod, path, name, description)
+        {
+            _options = options;
+            _dosProtector = new BasicDOSProtector(_options);
+        }
+
+        public virtual byte[] Handle(
+            string path, Stream request, IOSHttpRequest httpRequest, IOSHttpResponse httpResponse)
+        {
+            byte[] result;
+            RequestsReceived++;
+            string clientstring = GetClientString(httpRequest);
+            string endpoint = GetRemoteAddr(httpRequest);
+            if (_dosProtector.Process(clientstring, endpoint))
+                result = ProcessRequest(path, request, httpRequest, httpResponse);
+            else
+                result = ThrottledRequest(path, request, httpRequest, httpResponse);
+            if (_options.MaxConcurrentSessions > 0)
+                _dosProtector.ProcessEnd(clientstring, endpoint);
+            
+            RequestsHandled++;
+
+            return result;
+        }
+
+        protected virtual byte[] ProcessRequest(
+            string path, Stream request, IOSHttpRequest httpRequest, IOSHttpResponse httpResponse)
+        {
+            return null;
+        }
+
+        protected virtual byte[] ThrottledRequest(
+            string path, Stream request, IOSHttpRequest httpRequest, IOSHttpResponse httpResponse)
+        {
+            return new byte[0];
+        }
+
+        
+        private string GetRemoteAddr(IOSHttpRequest httpRequest)
+        {
+            string remoteaddr = string.Empty;
+            if (httpRequest.Headers["remote_addr"] != null)
+                remoteaddr = httpRequest.Headers["remote_addr"];
+
+            return remoteaddr;
+        }
+
+        private string GetClientString(IOSHttpRequest httpRequest)
+        {
+            string clientstring = string.Empty;
+
+            if (_options.AllowXForwardedFor && httpRequest.Headers["x-forwarded-for"] != null)
+                clientstring = httpRequest.Headers["x-forwarded-for"];
+            else
+                clientstring = GetRemoteAddr(httpRequest);
+
+            return clientstring;
+           
+        }
+    }
+}