src/routingTree.hpp

   1 /*
   2  *  anytun
   3  *
   4  *  The secure anycast tunneling protocol (satp) defines a protocol used
   5  *  for communication between any combination of unicast and anycast
   6  *  tunnel endpoints.  It has less protocol overhead than IPSec in Tunnel
   7  *  mode and allows tunneling of every ETHER TYPE protocol (e.g.
   8  *  ethernet, ip, arp ...). satp directly includes cryptography and
   9  *  message authentication based on the methodes used by SRTP.  It is
  10  *  intended to deliver a generic, scaleable and secure solution for
  11  *  tunneling and relaying of packets of any protocol.
  12  *
  13  *
  14  *  Copyright (C) 2007-2008 Othmar Gsenger, Erwin Nindl,
  15  *                          Christian Pointner <satp@wirdorange.org>
  16  *
  17  *  This file is part of Anytun.
  18  *
  19  *  Anytun is free software: you can redistribute it and/or modify
  20  *  it under the terms of the GNU General Public License version 3 as
  21  *  published by the Free Software Foundation.
  22  *
  23  *  Anytun is distributed in the hope that it will be useful,
  24  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  25  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  26  *  GNU General Public License for more details.
  27  *
  28  *  You should have received a copy of the GNU General Public License
  29  *  along with anytun.  If not, see <http://www.gnu.org/licenses/>.
  30  */
  31
  32 #ifndef __ROUTING_TREE_
  33 #define __ROUTING_TREE_
  34
  35 class RoutingTree {
  36
  37 public:
  38   template <class BinaryType>
  39   static void walk(BinaryType bytes ,RoutingTreeNode * node,u_int8_t length,u_int16_t mux)
  40   {
  41     for (int i=0; i<(length/8); i++)
  42     {
  43       if (!node->nodes_[bytes[i]])
  44         node->nodes_[bytes[i]] = new RoutingTreeNode;
  45       node=node->nodes_[bytes[i]];
  46     }
  47     if (length%8)
  48     {
  49       unsigned char idx=0xff;
  50       idx <<=8-(length%8);
  51       idx &= bytes[length/8];
  52       unsigned char maxidx=0xff;
  53       maxidx>>=(length%8);
  54       maxidx|=idx;
  55       for (unsigned char i=idx; i<=maxidx; i++)
  56       {
  57         if (!node->nodes_[i])
  58           node->nodes_[i] = new RoutingTreeNode;
  59         node->nodes_[i]->valid_=true;
  60         node->nodes_[i]->mux_=mux;
  61       }
  62     } else {
  63       node->valid_=true;
  64       node->mux_=mux;
  65     }
  66   }
  67
  68   template <class BinaryType>
  69   static u_int16_t find(BinaryType bytes ,RoutingTreeNode & root )
  70   {
  71     bool valid=0;
  72     u_int16_t mux=0;
  73     RoutingTreeNode * node = &root;
  74     if (root.valid_)
  75     {
  76       mux=root.mux_;
  77       valid=1;
  78     }
  79     for (size_t level=0;level<bytes.size();level++)
  80     {
  81       if (node->nodes_[bytes[level]])
  82       {
  83         node=node->nodes_[bytes[level]];
  84         if(node->valid_)
  85         {
  86           mux=node->mux_;
  87           valid=1;
  88         }
  89       } else {
  90         break;
  91       }
  92     }
  93     if(!valid)
  94       throw std::runtime_error("no route");
  95     return mux;
  96   }
  97
  98 };
  99
 100 #endif
 101
 102