1/*
2 *  OpenVPN -- An application to securely tunnel IP networks
3 *             over a single UDP port, with support for SSL/TLS-based
4 *             session authentication and key exchange,
5 *             packet encryption, packet authentication, and
6 *             packet compression.
7 *
8 *  Copyright (C) 2002-2010 OpenVPN Technologies, Inc. <sales@openvpn.net>
9 *
10 *  This program is free software; you can redistribute it and/or modify
11 *  it under the terms of the GNU General Public License version 2
12 *  as published by the Free Software Foundation.
13 *
14 *  This program is distributed in the hope that it will be useful,
15 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
16 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17 *  GNU General Public License for more details.
18 *
19 *  You should have received a copy of the GNU General Public License
20 *  along with this program (see the file COPYING included with this
21 *  distribution); if not, write to the Free Software Foundation, Inc.,
22 *  59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
23 */
24
25/*
26 * Each session is identified by a random 8-byte session identifier.
27 *
28 * For efficiency, the session id is only transmitted over the control
29 * channel (which only sees traffic occasionally when keys are being
30 * negotiated).  The data channel sees a smaller version of the session-id --
31 * it is called the key_id and is currently 2 bits long.
32 */
33
34#ifdef HAVE_CONFIG_H
35#include "config.h"
36#elif defined(_MSC_VER)
37#include "config-msvc.h"
38#endif
39
40#include "syshead.h"
41
42#if defined(ENABLE_CRYPTO) && defined(ENABLE_SSL)
43
44#include "error.h"
45#include "common.h"
46#include "crypto.h"
47#include "session_id.h"
48
49#include "memdbg.h"
50
51const struct session_id x_session_id_zero;
52
53void
54session_id_random (struct session_id *sid)
55{
56  prng_bytes (sid->id, SID_SIZE);
57}
58
59const char *
60session_id_print (const struct session_id *sid, struct gc_arena *gc)
61{
62  return format_hex (sid->id, SID_SIZE, 0, gc);
63}
64
65#else
66static void dummy(void) {}
67#endif /* ENABLE_CRYPTO && ENABLE_SSL*/
68