projects/traffcounter/rules_finder.cpp

   1 /*
   2  *    This program is free software; you can redistribute it and/or modify
   3  *    it under the terms of the GNU General Public License as published by
   4  *    the Free Software Foundation; either version 2 of the License, or
   5  *    (at your option) any later version.
   6  *
   7  *    This program is distributed in the hope that it will be useful,
   8  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
   9  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10  *    GNU General Public License for more details.
  11  *
  12  *    You should have received a copy of the GNU General Public License
  13  *    along with this program; if not, write to the Free Software
  14  *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  15  */
  16
  17 /*
  18  *    Author : Maxim Mamontov <faust@stargazer.dp.ua>
  19  */
  20
  21 /*
  22  $Revision: 1.3 $
  23  $Date: 2009/10/12 08:46:05 $
  24  $Author: faust $
  25  */
  26
  27 #include "rules_finder.h"
  28 #include "logger.h"
  29 #include "lock.h"
  30
  31 STG::RULES_FINDER::RULES_FINDER()
  32 {
  33     pthread_mutex_init(&mutex, NULL);
  34 }
  35
  36 STG::RULES_FINDER::~RULES_FINDER()
  37 {
  38     pthread_mutex_destroy(&mutex);
  39 }
  40
  41 void STG::RULES_FINDER::SetRules(const RULES & r)
  42 {
  43 SCOPED_LOCK lock(mutex);
  44 rules = r;
  45 }
  46
  47 int STG::RULES_FINDER::GetDir(const PENDING_PACKET & packet) const
  48 {
  49 bool addrMatch;
  50 bool portMatch;
  51
  52 STG::RULES::const_iterator ln;
  53 int ruleLine(1);
  54
  55 SCOPED_LOCK lock(mutex);
  56
  57 ln = rules.begin();
  58
  59 while (ln != rules.end())
  60     {
  61     addrMatch = false;
  62     portMatch = false;
  63
  64     // Port range
  65     switch (packet.direction) {
  66         case PENDING_PACKET::INCOMING:
  67             portMatch = (packet.sport >= ln->port1) &&
  68                         (packet.sport <= ln->port2);
  69             break;
  70         case PENDING_PACKET::OUTGOING:
  71             portMatch = (packet.dport >= ln->port1) &&
  72                         (packet.dport <= ln->port2);
  73             break;
  74         case PENDING_PACKET::LOCAL:
  75             portMatch = ((packet.sport >= ln->port1) &&
  76                         (packet.sport <= ln->port2)) ||
  77                         ((packet.dport >= ln->port1) &&
  78                         (packet.dport <= ln->port2));
  79             break;
  80         default:
  81             ++ruleLine;
  82             ++ln;
  83             continue;
  84     }
  85
  86     if (!portMatch) {
  87         ++ruleLine;
  88         ++ln;
  89         continue;
  90     }
  91
  92     /*portMatch = ((packet.sport >= ln->port1) &&
  93                  (packet.sport <= ln->port2) &&
  94                  (packet.direction == PENDING_PACKET::INCOMING)) ||
  95                 ((packet.dport >= ln->port1) &&
  96                  (packet.dport <= ln->port2) &&
  97                  (packet.direction == PENDING_PACKET::OUTGOING));*/
  98
  99     if (ln->proto != packet.proto)
 100         {
 101         // Is it a normal protcol number?
 102         if (ln->proto >= 0)
 103             {
 104             ++ruleLine;
 105             ++ln;
 106             continue;
 107             }
 108         else if (ln->proto == -2)
 109             {
 110             // -2 - TCP_UDP
 111             if (packet.proto != 6 &&
 112                 packet.proto != 17)
 113                 {
 114                 ++ruleLine;
 115                 ++ln;
 116                 continue;
 117                 }
 118             }
 119         // -1 - ALL
 120         }
 121
 122     switch (packet.direction) {
 123         case PENDING_PACKET::INCOMING:
 124             // From outer world to us
 125             addrMatch = (packet.saddr & ln->mask) == ln->ip;
 126             break;
 127         case PENDING_PACKET::OUTGOING:
 128             // From us to outer world
 129             addrMatch = (packet.daddr & ln->mask) == ln->ip;
 130             break;
 131         case PENDING_PACKET::LOCAL:
 132             // From us to us
 133             addrMatch = (packet.saddr & ln->mask) == ln->ip ||
 134                         (packet.daddr & ln->mask) == ln->ip;
 135             break;
 136         default:
 137             // From outer world to outer world
 138             ++ruleLine;
 139             ++ln;
 140             continue;
 141     }
 142
 143
 144     if (addrMatch)
 145         {
 146         // At this point ports and protocol are matched
 147         return ln->dir;
 148         }
 149
 150     ++ruleLine;
 151     ++ln;
 152     }   //while (ln != rules.end())
 153
 154 return -1;
 155 }