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) 2007-2008 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 version 3 as
  24  *  published by the Free Software Foundation.
  25  *
  26  *  uAnytun is distributed in the hope that it will be useful,
  27  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  28  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  29  *  GNU General Public License for more details.
  30  *
  31  *  You should have received a copy of the GNU General Public License
  32  *  along with uAnytun. If not, see <http://www.gnu.org/licenses/>.
  33  */
  34
  35 #ifndef _ENCRYPTED_PACKET_H_
  36 #define _ENCRYPTED_PACKET_H_
  37
  38 #define ENCRYPTED_PACKET_SIZE_MAX 1600
  39
  40 #define PAYLOAD_TYPE_TAP 0x6558
  41 #define PAYLOAD_TYPE_TUN 0x0000
  42 #define PAYLOAD_TYPE_TUN4 0x0800
  43 #define PAYLOAD_TYPE_TUN6 0x86DD
  44
  45 struct __attribute__ ((__packed__)) encrypted_packet_header_struct {
  46   seq_nr_t seq_nr_;
  47   sender_id_t sender_id_;
  48   mux_t mux_;
  49 };
  50 typedef struct encrypted_packet_header_struct encrypted_packet_header_t;
  51
  52 struct encrypted_packet_struct {
  53   u_int32_t payload_length_;
  54   u_int32_t auth_tag_length_;
  55   union __attribute__ ((__packed__)) {
  56     u_int8_t buf_[ENCRYPTED_PACKET_SIZE_MAX];
  57     encrypted_packet_header_t header_;
  58  } data_;
  59 };
  60 typedef struct encrypted_packet_struct encrypted_packet_t;
  61
  62 void encrypted_packet_init(encrypted_packet_t* packet, u_int32_t auth_tag_length);
  63
  64 u_int32_t encrypted_packet_get_minimum_length(encrypted_packet_t* packet);
  65
  66 u_int8_t* encrypted_packet_get_packet(encrypted_packet_t* packet);
  67 u_int32_t encrypted_packet_get_length(encrypted_packet_t* packet);
  68 void encrypted_packet_set_length(encrypted_packet_t* packet, u_int32_t len);
  69
  70 u_int8_t* encrypted_packet_get_payload(encrypted_packet_t* packet);
  71 u_int32_t encrypted_packet_get_payload_length(encrypted_packet_t* packet);
  72 void encrypted_packet_set_payload_length(encrypted_packet_t* packet, u_int32_t len);
  73
  74 u_int8_t* encrypted_packet_get_auth_portion(encrypted_packet_t* packet);
  75 u_int32_t encrypted_packet_get_auth_portion_length(encrypted_packet_t* packet);
  76
  77 u_int8_t* encrypted_packet_get_auth_tag(encrypted_packet_t* packet);
  78 u_int32_t encrypted_packet_get_auth_tag_length(encrypted_packet_t* packet);
  79
  80 seq_nr_t encrypted_packet_get_seq_nr(encrypted_packet_t* packet);
  81 void encrypted_packet_set_seq_nr(encrypted_packet_t* packet, seq_nr_t seq_nr);
  82
  83 sender_id_t encrypted_packet_get_sender_id(encrypted_packet_t* packet);
  84 void encrypted_packet_set_sender_id(encrypted_packet_t* packet, sender_id_t sender_id);
  85
  86 mux_t encrypted_packet_get_mux(encrypted_packet_t* packet);
  87 void encrypted_packet_set_mux(encrypted_packet_t* packet, mux_t mux);
  88
  89
  90 #endif