src/encryptedPacket.h

   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 _ENCRYPTED_PACKET_H_
  33 #define _ENCRYPTED_PACKET_H_
  34
  35 #include "datatypes.h"
  36 #include "buffer.h"
  37
  38 class Cipher;
  39 class EncryptedPacket : public Buffer
  40 {
  41 public:
  42
  43   /**
  44    * Packet constructor
  45    * @param the length of the payload
  46    * @param allow reallocation of buffer
  47    */
  48   EncryptedPacket(u_int32_t payload_length, bool allow_realloc = false);
  49
  50   /**
  51    * Packet destructor
  52    */
  53   ~EncryptedPacket() {};
  54
  55   /**
  56    * Get the length of the header
  57    * @return the length of the header
  58    */
  59   static u_int32_t getHeaderLength();
  60
  61   /**
  62    * Get the sequence number
  63    * @return seqence number
  64    */
  65   seq_nr_t getSeqNr() const;
  66
  67   /**
  68    * Set the seqence number
  69    * @param seq_nr sequence number
  70    */
  71   void setSeqNr(seq_nr_t seq_nr);
  72
  73   /**
  74    * Get the sender id
  75    * @return sender id
  76    */
  77   sender_id_t getSenderId() const;
  78
  79   /**
  80    * Set the sender id
  81    * @param sender_id sender id
  82    */
  83   void setSenderId(sender_id_t sender_id);
  84
  85   /**
  86    * Get the mulitplex id
  87    * @return multiplex id
  88    */
  89   mux_t getMux() const;
  90
  91   /**
  92    * Set the multiplex id
  93    * @param mux multiplex id
  94    */
  95   void setMux(mux_t mux);
  96
  97   /**
  98    * Set the header of a packet
  99    * @param seq_nr sequence number
 100    * @param sender_id sender id
 101    * @param mux multiplex id
 102    */
 103   void setHeader(seq_nr_t seq_nr, sender_id_t sender_id, mux_t mux);
 104
 105   /**
 106    * Get the length of the payload
 107    * @return the length of the payload
 108    */
 109   u_int32_t getPayloadLength() const;
 110
 111   /**
 112    * Set the length of the payload
 113    * @param length length of the payload
 114    */
 115   void setPayloadLength(u_int32_t payload_length);
 116
 117   /**
 118    * Get the the payload
 119    * @return the Pointer to the payload
 120    */
 121   u_int8_t* getPayload();
 122
 123
 124   u_int8_t* getAuthenticatedPortion();
 125   u_int32_t getAuthenticatedPortionLength();
 126
 127   void withAuthTag(bool b);
 128   void addAuthTag();
 129   void removeAuthTag();
 130   u_int8_t* getAuthTag();
 131   u_int32_t getAuthTagLength();
 132
 133 private:
 134   EncryptedPacket();
 135   EncryptedPacket(const EncryptedPacket &src);
 136
 137   void reinit();
 138
 139 #ifdef _MSC_VER
 140   #pragma pack(push, 1)
 141 #endif
 142   struct ATTR_PACKED HeaderStruct
 143   {
 144     seq_nr_t seq_nr;
 145     sender_id_t sender_id;
 146     mux_t mux;
 147   };
 148 #ifdef _MSC_VER
 149   #pragma pack(pop)
 150 #endif
 151
 152   struct HeaderStruct* header_;
 153         u_int8_t * payload_;
 154   u_int8_t * auth_tag_;
 155   static const u_int32_t AUTHTAG_SIZE = 10;  // TODO: hardcoded size
 156 };
 157
 158 #endif