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