authAlgo.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 anytun.org <satp@wirdorange.org>
  15  *
  16  *  This program is free software; you can redistribute it and/or modify
  17  *  it under the terms of the GNU General Public License version 2
  18  *  as published by the Free Software Foundation.
  19  *
  20  *  This program is distributed in the hope that it will be useful,
  21  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  22  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  23  *  GNU General Public License for more details.
  24  *
  25  *  You should have received a copy of the GNU General Public License
  26  *  along with this program (see the file COPYING included with this
  27  *  distribution); if not, write to the Free Software Foundation, Inc.,
  28  *  59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  29  */
  30
  31 #ifndef _AUTHALGO_H_
  32 #define _AUTHALGO_H_
  33
  34 #include "authTag.h"
  35 #include "datatypes.h"
  36 #include "buffer.h"
  37 #include "threadUtils.hpp"
  38
  39 #include <gcrypt.h>
  40
  41 class AuthAlgo
  42 {
  43 public:
  44   AuthAlgo() {};
  45   virtual ~AuthAlgo() {};
  46
  47   /**
  48    * set the key for the auth algo
  49    * @param key key for hmac calculation
  50    */
  51   virtual void setKey(Buffer key) = 0;
  52
  53   /**
  54    * calculate the sha1 hmac
  55    * @param buf buffer for message digest
  56    * @return sha1 hmac
  57    */
  58   virtual AuthTag calc(const Buffer& buf) = 0;
  59 };
  60
  61 //****** NullAuthAlgo ******
  62
  63 class NullAuthAlgo : public AuthAlgo
  64 {
  65 public:
  66   AuthTag calc(const Buffer& buf);
  67   void setKey(Buffer key) {};
  68 };
  69
  70
  71 //****** Sha1AuthAlgo ******
  72 //* HMAC SHA1 Auth Tag Generator Class
  73
  74 class Sha1AuthAlgo : public AuthAlgo
  75 {
  76 public:
  77   Sha1AuthAlgo();
  78   ~Sha1AuthAlgo();
  79
  80   void setKey(Buffer key);
  81   AuthTag calc(const Buffer& buf);
  82
  83 protected:
  84   gcry_md_hd_t ctx_;
  85   Mutex mutex_;
  86 };
  87
  88 #endif