src/encrypted_packet.h

   1 /*
   2  *  uAnytun
   3  *
   4  *  uAnytun is a tiny implementation of SATP. Unlike Anytun which is a full
   5  *  featured implementation uAnytun has no support for multiple connections
   6  *  or synchronisation. It is a small single threaded implementation intended
   7  *  to act as a client on small platforms.
   8  *  The secure anycast tunneling protocol (satp) defines a protocol used
   9  *  for communication between any combination of unicast and anycast
  10  *  tunnel endpoints.  It has less protocol overhead than IPSec in Tunnel
  11  *  mode and allows tunneling of every ETHER TYPE protocol (e.g.
  12  *  ethernet, ip, arp ...). satp directly includes cryptography and
  13  *  message authentication based on the methodes used by SRTP.  It is
  14  *  intended to deliver a generic, scaleable and secure solution for
  15  *  tunneling and relaying of packets of any protocol.
  16  *
  17  *
  18  *  Copyright (C) 2007-2010 Christian Pointner <equinox@anytun.org>
  19  *
  20  *  This file is part of uAnytun.
  21  *
  22  *  uAnytun is free software: you can redistribute it and/or modify
  23  *  it under the terms of the GNU General Public License as published by
  24  *  the Free Software Foundation, either version 3 of the License, or
  25  *  any later version.
  26  *
  27  *  uAnytun is distributed in the hope that it will be useful,
  28  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  29  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  30  *  GNU General Public License for more details.
  31  *
  32  *  You should have received a copy of the GNU General Public License
  33  *  along with uAnytun. If not, see <http://www.gnu.org/licenses/>.
  34  */
  35
  36 #ifndef UANYTUN_encrypted_packet_h_INCLUDED
  37 #define UANYTUN_encrypted_packet_h_INCLUDED
  38
  39 #define ENCRYPTED_PACKET_SIZE_MAX 1600
  40
  41 #define PAYLOAD_TYPE_TAP 0x6558
  42 #define PAYLOAD_TYPE_TUN 0x0000
  43 #define PAYLOAD_TYPE_TUN4 0x0800
  44 #define PAYLOAD_TYPE_TUN6 0x86DD
  45
  46 struct __attribute__ ((__packed__)) encrypted_packet_header_struct {
  47   seq_nr_t seq_nr_;
  48   sender_id_t sender_id_;
  49   mux_t mux_;
  50 };
  51 typedef struct encrypted_packet_header_struct encrypted_packet_header_t;
  52
  53 struct encrypted_packet_struct {
  54   u_int32_t payload_length_;
  55   u_int32_t auth_tag_length_;
  56   union __attribute__ ((__packed__)) {
  57     u_int8_t buf_[ENCRYPTED_PACKET_SIZE_MAX];
  58     encrypted_packet_header_t header_;
  59  } data_;
  60 };
  61 typedef struct encrypted_packet_struct encrypted_packet_t;
  62
  63 void encrypted_packet_init(encrypted_packet_t* packet, u_int32_t auth_tag_length);
  64
  65 u_int32_t encrypted_packet_get_minimum_length(encrypted_packet_t* packet);
  66
  67 u_int8_t* encrypted_packet_get_packet(encrypted_packet_t* packet);
  68 u_int32_t encrypted_packet_get_length(encrypted_packet_t* packet);
  69 void encrypted_packet_set_length(encrypted_packet_t* packet, u_int32_t len);
  70
  71 u_int8_t* encrypted_packet_get_payload(encrypted_packet_t* packet);
  72 u_int32_t encrypted_packet_get_payload_length(encrypted_packet_t* packet);
  73 void encrypted_packet_set_payload_length(encrypted_packet_t* packet, u_int32_t len);
  74
  75 u_int8_t* encrypted_packet_get_auth_portion(encrypted_packet_t* packet);
  76 u_int32_t encrypted_packet_get_auth_portion_length(encrypted_packet_t* packet);
  77
  78 u_int8_t* encrypted_packet_get_auth_tag(encrypted_packet_t* packet);
  79 u_int32_t encrypted_packet_get_auth_tag_length(encrypted_packet_t* packet);
  80
  81 seq_nr_t encrypted_packet_get_seq_nr(encrypted_packet_t* packet);
  82 void encrypted_packet_set_seq_nr(encrypted_packet_t* packet, seq_nr_t seq_nr);
  83
  84 sender_id_t encrypted_packet_get_sender_id(encrypted_packet_t* packet);
  85 void encrypted_packet_set_sender_id(encrypted_packet_t* packet, sender_id_t sender_id);
  86
  87 mux_t encrypted_packet_get_mux(encrypted_packet_t* packet);
  88 void encrypted_packet_set_mux(encrypted_packet_t* packet, mux_t mux);
  89
  90
  91 #endif