/* *  OpenVPN -- An application to securely tunnel IP networks *             over a single UDP port, with support for TLS-based *             session authentication and key exchange, *             packet encryption, packet authentication, and *             packet compression. * *  Copyright (C) 2002 James Yonan <jim@yonan.net> * *  This program is free software; you can redistribute it and/or modify *  it under the terms of the GNU General Public License as published by *  the Free Software Foundation; either version 2 of the License, or *  (at your option) any later version. * *  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 (see the file COPYING included with this *  distribution); if not, write to the Free Software Foundation, Inc., *  59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */#ifdef USE_LZO#include "lzo1x.h"#include "buffer.h"#include "mtu.h"#include "common.h"/* * Use LZO compress routine lzo1x_1_15_compress which is described * as faster but needs a bit more memory than the standard routine. * Use safe decompress (i.e. check for buffer overflows). * You may want to use the non-safe version * of decompress if speed is essential and if you know * that you will always be using a MAC to verify the * integrity of incoming packets. */#define LZO_COMPRESS    lzo1x_1_15_compress#define LZO_WORKSPACE	LZO1X_1_15_MEM_COMPRESS#define LZO_DECOMPRESS  lzo1x_decompress_safe#define LZO_EXTRA_BUFFER(len) ((len)/64 + 16 + 3)	/* LZO worst case size expansion. *//* * Don't try to compress any packet smaller than this. */#define COMPRESS_THRESHOLD 100/* * Adaptive compress parameters */#define AC_SAMP_SEC    2      /* number of seconds in sample period */#define AC_MIN_BYTES   1000   /* sample period must have at least n bytes				 to be valid for testing */#define AC_SAVE_PCT    5      /* turn off compress if we didn't save at				 least this % during sample period */#define AC_OFF_SEC     60     /* if we turn off compression, don't do sample				 retest for n seconds */struct lzo_adaptive_compress {  bool enabled;  bool compress_state;  time_t next;  int n_total;  int n_comp;};/* * Compress and Uncompress routines. */struct lzo_compress_workspace{  lzo_voidp wmem;  int wmem_size;  struct lzo_adaptive_compress ac;  /* statistics */  counter_type pre_decompress;  counter_type post_decompress;  counter_type pre_compress;  counter_type post_compress;};void lzo_adjust_frame_parameters(struct frame *frame);void lzo_compress_init (struct lzo_compress_workspace *lzowork, bool adaptive);void lzo_compress_uninit (struct lzo_compress_workspace *lzowork);void lzo_compress (struct buffer *buf, struct buffer work,		   struct lzo_compress_workspace *lzowork,		   const struct frame* frame,		   const time_t current);void lzo_decompress (struct buffer *buf, struct buffer work,		     struct lzo_compress_workspace *lzowork,		     const struct frame* frame);void lzo_print_stats (struct lzo_compress_workspace *lzo_compwork);#endif /* USE_LZO */