/*
  *  OpenVPN -- An application to securely tunnel IP networks
  *             over a single UDP port, with support for SSL/TLS-based
  *             session authentication and key exchange,
  *             packet encryption, packet authentication, and
  *             packet compression.
  *

  *  Copyright (C) 2002-2018 OpenVPN Inc <sales@openvpn.net>

  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License version 2
  *  as published by the Free Software Foundation.
  *
  *  This program is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  *  GNU General Public License for more details.
  *

  *  You should have received a copy of the GNU General Public License along
  *  with this program; if not, write to the Free Software Foundation, Inc.,
  *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

  */
 
 /*
  * Each session is identified by a random 8-byte session identifier.
  *
  * For efficiency, the session id is only transmitted over the control
  * channel (which only sees traffic occasionally when keys are being
  * negotiated).
  */
 
 #ifndef SESSION_ID_H
 #define SESSION_ID_H
 
 #include "basic.h"
 #include "buffer.h"
 
 struct session_id
 {

     uint8_t id[8];

 };
 
 extern const struct session_id x_session_id_zero;
 

 #define SID_SIZE (sizeof(x_session_id_zero.id))

 
 static inline bool

 session_id_equal(const struct session_id *sid1,
                  const struct session_id *sid2)

 {

     return !memcmp(sid1->id, sid2->id, SID_SIZE);

 }
 
 static inline bool

 session_id_defined(const struct session_id *sid1)

 {

     return memcmp(sid1->id, &x_session_id_zero.id, SID_SIZE) != 0;

 }
 
 static inline bool

 session_id_read(struct session_id *sid, struct buffer *buf)

 {

     return buf_read(buf, sid->id, SID_SIZE);

 }
 
 static inline bool

 session_id_write_prepend(const struct session_id *sid, struct buffer *buf)

 {

     return buf_write_prepend(buf, sid->id, SID_SIZE);

 }
 
 static inline bool

 session_id_write(const struct session_id *sid, struct buffer *buf)

 {

     return buf_write(buf, sid->id, SID_SIZE);

 }
 

 void session_id_random(struct session_id *sid);

 const char *session_id_print(const struct session_id *sid, struct gc_arena *gc);

 
 #endif /* SESSION_ID_H */