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/* Copyright (C) 2002-2005 RealVNC Ltd. All Rights Reserved.
*
* This is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this software; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
* USA.
*/
//
// Blacklist.h - Handling of black-listed entities.
// Just keeps a table mapping strings to timing information, including
// how many times the entry has been black-listed and when to next
// put it on probation (e.g. allow a connection in from the host, and
// re-blacklist it if that fails).
//
#ifndef __RFB_BLACKLIST_H__
#define __RFB_BLACKLIST_H__
#include <string.h>
#include <time.h>
#include <map>
#include <rfb/Configuration.h>
#include <rfb/util.h>
namespace rfb {
//
// -=- Blacklist handler
//
// Parameters include a threshold after which to blacklist the named
// host, and a timeout after which to re-consider them.
//
// Threshold means that isBlackmarked can be called that number of times
// before it will return true.
//
// Timeout means that after that many seconds, the next call to isBlackmarked
// will return false. At the same time, the timeout is doubled, so that the
// next calls will fail, until the timeout expires again or clearBlackmark is
// called.
//
// When clearBlackMark is called, the corresponding entry is completely
// removed, causing the next isBlackmarked call to return false.
// KNOWN BUG: Client can keep making rejected requests, thus increasing
// their timeout. If client does this for 30 years, timeout may wrap round
// to a very small value again.
// THIS CLASS IS NOT THREAD-SAFE!
class Blacklist {
public:
Blacklist();
~Blacklist();
bool isBlackmarked(const char* name);
void clearBlackmark(const char* name);
static IntParameter threshold;
static IntParameter initialTimeout;
protected:
struct ltStr {
bool operator()(const char* s1, const char* s2) const {
return strcmp(s1, s2) < 0;
};
};
struct BlacklistInfo {
int marks;
time_t blockUntil;
unsigned int blockTimeout;
};
typedef std::map<const char*,BlacklistInfo,ltStr> BlacklistMap;
BlacklistMap blm;
};
}
#endif
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