* Refactor

* Break out common BasicDOSProtector code into separate class.
This commit is contained in:
teravus
2013-10-07 23:19:50 -05:00
parent f76cc6036e
commit 75fdd6054d
7 changed files with 218 additions and 415 deletions

View File

@@ -25,13 +25,7 @@
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
using System;
using System.Collections;
using System.Collections.Generic;
using System.Reflection;
using System.Net;
using OpenSim.Framework;
using log4net;
namespace OpenSim.Framework.Servers.HttpServer
{
@@ -39,147 +33,26 @@ namespace OpenSim.Framework.Servers.HttpServer
{
private readonly GenericHTTPMethod _normalMethod;
private readonly GenericHTTPMethod _throttledMethod;
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;
public GenericHTTPDOSProtector(GenericHTTPMethod normalMethod, GenericHTTPMethod throttledMethod, BasicDosProtectorOptions options)
{
_normalMethod = normalMethod;
_throttledMethod = throttledMethod;
_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 Hashtable Process(Hashtable request)
{
if (_options.MaxRequestsInTimeframe < 1)
if (_dosProtector.Process(GetClientString(request), GetRemoteAddr(request)))
return _normalMethod(request);
if (_options.RequestTimeSpan.TotalMilliseconds < 1)
return _normalMethod(request);
string clientstring = GetClientString(request);
_lockSlim.EnterReadLock();
if (_tempBlocked.ContainsKey(clientstring))
{
_lockSlim.ExitReadLock();
if (_options.ThrottledAction == ThrottleAction.DoThrottledMethod)
return _throttledMethod(request);
else
throw new System.Security.SecurityException("Throttled");
}
_lockSlim.ExitReadLock();
_generalRequestTimes.Put(Util.EnvironmentTickCount());
if (_generalRequestTimes.Size == _generalRequestTimes.Capacity &&
(Util.EnvironmentTickCountSubtract(Util.EnvironmentTickCount(), _generalRequestTimes.Get()) <
_options.RequestTimeSpan.TotalMilliseconds))
{
//Trigger deeper inspection
if (DeeperInspection(request))
return _normalMethod(request);
if (_options.ThrottledAction == ThrottleAction.DoThrottledMethod)
return _throttledMethod(request);
else
throw new System.Security.SecurityException("Throttled");
}
Hashtable resp = null;
try
{
resp = _normalMethod(request);
}
catch (Exception)
{
throw;
}
return resp;
else
return _throttledMethod(request);
}
private bool DeeperInspection(Hashtable request)
{
lock (_deeperInspection)
{
string clientstring = GetClientString(request);
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(request));
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(Hashtable request)
{
string remoteaddr = "";