* Refactor

* Break out common BasicDOSProtector code into separate class.

1 files changed, 8 insertions, 136 deletions

diff --git a/OpenSim/Framework/Servers/HttpServer/BaseStreamHandlerBasicDOSProtector.cs b/OpenSim/Framework/Servers/HttpServer/BaseStreamHandlerBasicDOSProtector.cs
index 8fc9a8a..9b8b8c2 100644
--- a/OpenSim/Framework/Servers/HttpServer/BaseStreamHandlerBasicDOSProtector.cs
+++ b/OpenSim/Framework/Servers/HttpServer/BaseStreamHandlerBasicDOSProtector.cs
@@ -25,10 +25,7 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 using OpenSim.Framework;
-using System.Collections.Generic;
 using System.IO;
-using System.Reflection;
-using log4net;
 
 namespace OpenSim.Framework.Servers.HttpServer
 {
@@ -40,61 +37,17 @@ namespace OpenSim.Framework.Servers.HttpServer
     /// </remarks>
     public abstract class BaseStreamHandlerBasicDOSProtector : BaseRequestHandler, IStreamedRequestHandler
     {
-        private readonly CircularBuffer<int> _generalRequestTimes;
+       
         private readonly BasicDosProtectorOptions _options;
-        private readonly Dictionary<string, CircularBuffer<int>> _deeperInspection;
-        private readonly Dictionary<string, int> _tempBlocked;
-        private readonly System.Timers.Timer _forgetTimer;
-        private static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
-        private readonly System.Threading.ReaderWriterLockSlim _lockSlim = new System.Threading.ReaderWriterLockSlim();
+        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)
         {
-            _generalRequestTimes = new CircularBuffer<int>(options.MaxRequestsInTimeframe + 1, true);
-            _generalRequestTimes.Put(0);
             _options = options;
-            _deeperInspection = new Dictionary<string, CircularBuffer<int>>();
-            _tempBlocked = new Dictionary<string, int>();
-            _forgetTimer = new System.Timers.Timer();
-            _forgetTimer.Elapsed += delegate
-            {
-                _forgetTimer.Enabled = false;
-
-                List<string> removes = new List<string>();
-                _lockSlim.EnterReadLock();
-                foreach (string str in _tempBlocked.Keys)
-                {
-                    if (
-                        Util.EnvironmentTickCountSubtract(Util.EnvironmentTickCount(),
-                                                          _tempBlocked[str]) > 0)
-                        removes.Add(str);
-                }
-                _lockSlim.ExitReadLock();
-                lock (_deeperInspection)
-                {
-                    _lockSlim.EnterWriteLock();
-                    for (int i = 0; i < removes.Count; i++)
-                    {
-                        _tempBlocked.Remove(removes[i]);
-                        _deeperInspection.Remove(removes[i]);
-                    }
-                    _lockSlim.ExitWriteLock();
-                }
-                foreach (string str in removes)
-                {
-                    m_log.InfoFormat("[{0}] client: {1} is no longer blocked.",
-                                     _options.ReportingName, str);
-                }
-                _lockSlim.EnterReadLock();
-                if (_tempBlocked.Count > 0)
-                    _forgetTimer.Enabled = true;
-                _lockSlim.ExitReadLock();
-            };
-
-            _forgetTimer.Interval = _options.ForgetTimeSpan.TotalMilliseconds;
+            _dosProtector = new BasicDOSProtector(_options);
         }
 
         public virtual byte[] Handle(
@@ -102,58 +55,13 @@ namespace OpenSim.Framework.Servers.HttpServer
         {
             byte[] result;
             RequestsReceived++;
-            //httpRequest.Headers
 
-            if (_options.MaxRequestsInTimeframe < 1 || _options.RequestTimeSpan.TotalMilliseconds < 1)
-            {
+            if (_dosProtector.Process(GetClientString(httpRequest), GetRemoteAddr(httpRequest)))
                 result = ProcessRequest(path, request, httpRequest, httpResponse);
-                RequestsHandled++;
-                return result;
-                
-            }
-
-            string clientstring = GetClientString(httpRequest);
-
-            _lockSlim.EnterReadLock();
-            if (_tempBlocked.ContainsKey(clientstring))
-            {
-                _lockSlim.ExitReadLock();
-
-                if (_options.ThrottledAction == ThrottleAction.DoThrottledMethod)
-                {
-                    result = ThrottledRequest(path, request, httpRequest, httpResponse);
-                    RequestsHandled++;
-                    return result;
-                }
-                else
-                    throw new System.Security.SecurityException("Throttled");
-            }
-            _lockSlim.ExitReadLock();
-
-            _generalRequestTimes.Put(Util.EnvironmentTickCount());
+            else
+                result = ThrottledRequest(path, request, httpRequest, httpResponse);
 
-            if (_generalRequestTimes.Size == _generalRequestTimes.Capacity &&
-                (Util.EnvironmentTickCountSubtract(Util.EnvironmentTickCount(), _generalRequestTimes.Get()) <
-                 _options.RequestTimeSpan.TotalMilliseconds))
-            {
-                //Trigger deeper inspection
-                if (DeeperInspection(httpRequest))
-                {
-                    result = ProcessRequest(path, request, httpRequest, httpResponse);
-                    RequestsHandled++;
-                    return result;
-                }
-                if (_options.ThrottledAction == ThrottleAction.DoThrottledMethod)
-                {
-                    result = ThrottledRequest(path, request, httpRequest, httpResponse);
-                    RequestsHandled++;
-                    return result;
-                }
-                else
-                    throw new System.Security.SecurityException("Throttled");
-            }
-           
-            result =ProcessRequest(path, request, httpRequest, httpResponse);
+            
             RequestsHandled++;
 
             return result;
@@ -171,43 +79,7 @@ namespace OpenSim.Framework.Servers.HttpServer
             return new byte[0];
         }
 
-        private bool DeeperInspection(IOSHttpRequest httpRequest)
-        {
-            lock (_deeperInspection)
-            {
-                string clientstring = GetClientString(httpRequest);
-
-
-                if (_deeperInspection.ContainsKey(clientstring))
-                {
-                    _deeperInspection[clientstring].Put(Util.EnvironmentTickCount());
-                    if (_deeperInspection[clientstring].Size == _deeperInspection[clientstring].Capacity &&
-                        (Util.EnvironmentTickCountSubtract(Util.EnvironmentTickCount(), _deeperInspection[clientstring].Get()) <
-                         _options.RequestTimeSpan.TotalMilliseconds))
-                    {
-                        _lockSlim.EnterWriteLock();
-                        if (!_tempBlocked.ContainsKey(clientstring))
-                            _tempBlocked.Add(clientstring, Util.EnvironmentTickCount() + (int)_options.ForgetTimeSpan.TotalMilliseconds);
-                        else
-                            _tempBlocked[clientstring] = Util.EnvironmentTickCount() + (int)_options.ForgetTimeSpan.TotalMilliseconds;
-                        _lockSlim.ExitWriteLock();
-
-                        m_log.WarnFormat("[{0}]: client: {1} is blocked for {2} milliseconds, X-ForwardedForAllowed status is {3}, endpoint:{4}", _options.ReportingName, clientstring, _options.ForgetTimeSpan.TotalMilliseconds, _options.AllowXForwardedFor, GetRemoteAddr(httpRequest));
-                        return false;
-                    }
-                    //else
-                    //   return true;
-                }
-                else
-                {
-                    _deeperInspection.Add(clientstring, new CircularBuffer<int>(_options.MaxRequestsInTimeframe + 1, true));
-                    _deeperInspection[clientstring].Put(Util.EnvironmentTickCount());
-                    _forgetTimer.Enabled = true;
-                }
-
-            }
-            return true;
-        }
+        
         private string GetRemoteAddr(IOSHttpRequest httpRequest)
         {
             string remoteaddr = string.Empty;