/*
* ppp-comp.h - Definitions for doing PPP packet compression.
*
* Copyright 1994-1998 Paul Mackerras.
*
* 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.
*/
#ifndef _UAPI_NET_PPP_COMP_H
#define _UAPI_NET_PPP_COMP_H


/*
* CCP codes.
*/

#define CCP_CONFREQ 1
#define CCP_CONFACK 2
#define CCP_TERMREQ 5
#define CCP_TERMACK 6
#define CCP_RESETREQ 14
#define CCP_RESETACK 15

/*
* Max # bytes for a CCP option
*/

#define CCP_MAX_OPTION_LENGTH 32

/*
* Parts of a CCP packet.
*/

#define CCP_CODE(dp) ((dp)[0])
#define CCP_ID(dp) ((dp)[1])
#define CCP_LENGTH(dp) (((dp)[2] << 8) + (dp)[3])
#define CCP_HDRLEN 4

#define CCP_OPT_CODE(dp) ((dp)[0])
#define CCP_OPT_LENGTH(dp) ((dp)[1])
#define CCP_OPT_MINLEN 2

/*
* Definitions for BSD-Compress.
*/

#define CI_BSD_COMPRESS 21 /* config. option for BSD-Compress */
#define CILEN_BSD_COMPRESS 3 /* length of config. option */

/* Macros for handling the 3rd byte of the BSD-Compress config option. */
#define BSD_NBITS(x) ((x) & 0x1F) /* number of bits requested */
#define BSD_VERSION(x) ((x) >> 5) /* version of option format */
#define BSD_CURRENT_VERSION 1 /* current version number */
#define BSD_MAKE_OPT(v, n) (((v) << 5) | (n))

#define BSD_MIN_BITS 9 /* smallest code size supported */
#define BSD_MAX_BITS 15 /* largest code size supported */

/*
* Definitions for Deflate.
*/

#define CI_DEFLATE 26 /* config option for Deflate */
#define CI_DEFLATE_DRAFT 24 /* value used in original draft RFC */
#define CILEN_DEFLATE 4 /* length of its config option */

#define DEFLATE_MIN_SIZE 9
#define DEFLATE_MAX_SIZE 15
#define DEFLATE_METHOD_VAL 8
#define DEFLATE_SIZE(x) (((x) >> 4) + 8)
#define DEFLATE_METHOD(x) ((x) & 0x0F)
#define DEFLATE_MAKE_OPT(w) ((((w) - 8) << 4) + DEFLATE_METHOD_VAL)
#define DEFLATE_CHK_SEQUENCE 0

/*
* Definitions for MPPE.
*/

#define CI_MPPE 18 /* config option for MPPE */
#define CILEN_MPPE 6 /* length of config option */

/*
* Definitions for other, as yet unsupported, compression methods.
*/

#define CI_PREDICTOR_1 1 /* config option for Predictor-1 */
#define CILEN_PREDICTOR_1 2 /* length of its config option */
#define CI_PREDICTOR_2 2 /* config option for Predictor-2 */
#define CILEN_PREDICTOR_2 2 /* length of its config option */


#endif /* _UAPI_NET_PPP_COMP_H */