/* $NetBSD: ppp-comp.h,v 1.16 2008/11/29 23:15:20 cube Exp $ */
/*
* ppp-comp.h - Definitions for doing PPP packet compression.
*
* Copyright (c) 1989-2002 Paul Mackerras. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The name(s) of the authors of this software must not be used to
* endorse or promote products derived from this software without
* prior written permission.
*
* 4. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by Paul Mackerras
* <paulus@samba.org>".
*
* THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO
* THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
* SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
* AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
* OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#ifndef _NET_PPP_COMP_H_
#define _NET_PPP_COMP_H_
/*
* The following symbols control whether we include code for
* various compression methods.
*/
#ifndef DO_BSD_COMPRESS
#define DO_BSD_COMPRESS 1 /* by default, include BSD-Compress */
#endif
#ifndef DO_DEFLATE
#define DO_DEFLATE 1 /* by default, include Deflate */
#endif
#define DO_PREDICTOR_1 0
#define DO_PREDICTOR_2 0
/*
* How many entries to make available in the compressors table
*/
#ifndef PPP_COMPRESSORS_MAX
#define PPP_COMPRESSORS_MAX 8
#endif
/*
* Structure giving methods for compression/decompression.
*/
#ifdef PACKETPTR
#include <sys/queue.h>
struct compressor {
int compress_proto; /* CCP compression protocol number */
/* Allocate space for a compressor (transmit side) */
void *(*comp_alloc)(u_char *, int);
/* Free space used by a compressor */
void (*comp_free)(void *);
/* Initialize a compressor */
int (*comp_init)(void *, u_char *, int, int, int, int);
/* Reset a compressor */
void (*comp_reset)(void *);
/* Compress a packet */
int (*compress)(void *, PACKETPTR *, PACKETPTR, int, int);
/* Return compression statistics */
void (*comp_stat)(void *, struct compstat *);
/* Allocate space for a decompressor (receive side) */
void *(*decomp_alloc)(u_char *, int);
/* Free space used by a decompressor */
void (*decomp_free)(void *);
/* Initialize a decompressor */
int (*decomp_init)(void *, u_char *, int, int, int, int, int);
/* Reset a decompressor */
void (*decomp_reset)(void *);
/* Decompress a packet. */
int (*decompress)(void *, PACKETPTR, PACKETPTR *);
/* Update state for an incompressible packet received */
void (*incomp)(void *, PACKETPTR);
/* Return decompression statistics */
void (*decomp_stat)(void *, struct compstat *);
LIST_ENTRY(compressor) comp_list;
unsigned int comp_refcnt;
};
#endif /* PACKETPTR */
/*
* Return values for decompress routine.
* We need to make these distinctions so that we can disable certain
* useful functionality, namely sending a CCP reset-request as a result
* of an error detected after decompression. This is to avoid infringing
* a patent held by Motorola.
* Don't you just lurve software patents.
*/
#define DECOMP_OK 0 /* everything went OK */
#define DECOMP_ERROR 1 /* error detected before decomp. */
#define DECOMP_FATALERROR 2 /* error detected after decomp. */
/*
* CCP codes.
*/
#define CCP_CONFREQ 1
#define CCP_CONFACK 2
#define CCP_CONFNAK 3
#define CCP_CONFREJ 4
#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 64
/*
* 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 8
#define DEFLATE_MAX_SIZE 15
#define DEFLATE_METHOD_VAL 8
#define DEFLATE_SIZE(x) (((x) >> 4) + DEFLATE_MIN_SIZE)
#define DEFLATE_METHOD(x) ((x) & 0x0F)
#define DEFLATE_MAKE_OPT(w) ((((w) - DEFLATE_MIN_SIZE) << 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 */
#define MPPE_PAD 4 /* MPPE growth per frame */
#define MPPE_MAX_KEY_LEN 16 /* largest key length (128-bit) */
/* option bits for ccp_options.mppe */
#define MPPE_OPT_40 0x01 /* 40 bit */
#define MPPE_OPT_128 0x02 /* 128 bit */
#define MPPE_OPT_STATEFUL 0x04 /* stateful mode */
/* unsupported opts */
#define MPPE_OPT_56 0x08 /* 56 bit */
#define MPPE_OPT_MPPC 0x10 /* MPPC compression */
#define MPPE_OPT_D 0x20 /* Unknown */
#define MPPE_OPT_UNSUPPORTED (MPPE_OPT_56|MPPE_OPT_MPPC|MPPE_OPT_D)
#define MPPE_OPT_UNKNOWN 0x40 /* Bits !defined in RFC 3078 were set */
/*
* This is not nice ... the alternative is a bitfield struct though.
* And unfortunately, we cannot share the same bits for the option
* names above since C and H are the same bit. We could do a uint32_t
* but then we have to do a htonl() all the time and/or we still need
* to know which octet is which.
*/
#define MPPE_C_BIT 0x01 /* MPPC */
#define MPPE_D_BIT 0x10 /* Obsolete, usage unknown */
#define MPPE_L_BIT 0x20 /* 40-bit */
#define MPPE_S_BIT 0x40 /* 128-bit */
#define MPPE_M_BIT 0x80 /* 56-bit, not supported */
#define MPPE_H_BIT 0x01 /* Stateless (in a different byte) */
/* Does not include H bit; used for least significant octet only. */
#define MPPE_ALL_BITS (MPPE_D_BIT|MPPE_L_BIT|MPPE_S_BIT|MPPE_M_BIT|MPPE_H_BIT)
/* Build a CI from mppe opts (see RFC 3078) */
#define MPPE_OPTS_TO_CI(opts, ci) \
do { \
u_char *ptr = ci; /* u_char[4] */ \
\
/* H bit */ \
if (opts & MPPE_OPT_STATEFUL) \
*ptr++ = 0x0; \
else \
*ptr++ = MPPE_H_BIT; \
*ptr++ = 0; \
*ptr++ = 0; \
\
/* S,L bits */ \
*ptr = 0; \
if (opts & MPPE_OPT_128) \
*ptr |= MPPE_S_BIT; \
if (opts & MPPE_OPT_40) \
*ptr |= MPPE_L_BIT; \
/* M,D,C bits not supported */ \
} while (/* CONSTCOND */ 0)
/* The reverse of the above */
#define MPPE_CI_TO_OPTS(ci, opts) \
do { \
u_char *ptr = ci; /* u_char[4] */ \
\
opts = 0; \
\
/* H bit */ \
if (!(ptr[0] & MPPE_H_BIT)) \
opts |= MPPE_OPT_STATEFUL; \
\
/* S,L bits */ \
if (ptr[3] & MPPE_S_BIT) \
opts |= MPPE_OPT_128; \
if (ptr[3] & MPPE_L_BIT) \
opts |= MPPE_OPT_40; \
\
/* M,D,C bits */ \
if (ptr[3] & MPPE_M_BIT) \
opts |= MPPE_OPT_56; \
if (ptr[3] & MPPE_D_BIT) \
opts |= MPPE_OPT_D; \
if (ptr[3] & MPPE_C_BIT) \
opts |= MPPE_OPT_MPPC; \
\
/* Other bits */ \
if (ptr[0] & ~MPPE_H_BIT) \
opts |= MPPE_OPT_UNKNOWN; \
if (ptr[1] || ptr[2]) \
opts |= MPPE_OPT_UNKNOWN; \
if (ptr[3] & ~MPPE_ALL_BITS) \
opts |= MPPE_OPT_UNKNOWN; \
} while (/* CONSTCOND */ 0)
/*
* 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 /* !_NET_PPP_COMP_H_ */