1*0Sstevel@tonic-gate /* 2*0Sstevel@tonic-gate * CDDL HEADER START 3*0Sstevel@tonic-gate * 4*0Sstevel@tonic-gate * The contents of this file are subject to the terms of the 5*0Sstevel@tonic-gate * Common Development and Distribution License, Version 1.0 only 6*0Sstevel@tonic-gate * (the "License"). You may not use this file except in compliance 7*0Sstevel@tonic-gate * with the License. 8*0Sstevel@tonic-gate * 9*0Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10*0Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing. 11*0Sstevel@tonic-gate * See the License for the specific language governing permissions 12*0Sstevel@tonic-gate * and limitations under the License. 13*0Sstevel@tonic-gate * 14*0Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each 15*0Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16*0Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the 17*0Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying 18*0Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner] 19*0Sstevel@tonic-gate * 20*0Sstevel@tonic-gate * CDDL HEADER END 21*0Sstevel@tonic-gate * 22*0Sstevel@tonic-gate * Copyright 2000 Sun Microsystems, Inc. All rights reserved. 23*0Sstevel@tonic-gate * Use is subject to license terms. 24*0Sstevel@tonic-gate */ 25*0Sstevel@tonic-gate 26*0Sstevel@tonic-gate #ifndef _CRCMODEL_H 27*0Sstevel@tonic-gate #define _CRCMODEL_H 28*0Sstevel@tonic-gate 29*0Sstevel@tonic-gate #pragma ident "%Z%%M% %I% %E% SMI" 30*0Sstevel@tonic-gate 31*0Sstevel@tonic-gate #ifdef SOLARIS_UNIX 32*0Sstevel@tonic-gate #include <sys/types.h> 33*0Sstevel@tonic-gate #else 34*0Sstevel@tonic-gate typedef long uint32_t; 35*0Sstevel@tonic-gate #endif 36*0Sstevel@tonic-gate 37*0Sstevel@tonic-gate #ifdef __cplusplus 38*0Sstevel@tonic-gate extern "C" { 39*0Sstevel@tonic-gate #endif 40*0Sstevel@tonic-gate 41*0Sstevel@tonic-gate /* 42*0Sstevel@tonic-gate * 43*0Sstevel@tonic-gate * Start of crcmodel.h 44*0Sstevel@tonic-gate * 45*0Sstevel@tonic-gate * 46*0Sstevel@tonic-gate * Author : Ross Williams (ross@guest.adelaide.edu.au.). 47*0Sstevel@tonic-gate * Date : 3 June 1993. 48*0Sstevel@tonic-gate * Status : Public domain. 49*0Sstevel@tonic-gate * 50*0Sstevel@tonic-gate * Description : This is the header (.h) file for the reference 51*0Sstevel@tonic-gate * implementation of the Rocksoft^tm Model CRC Algorithm. For more 52*0Sstevel@tonic-gate * information on the Rocksoft^tm Model CRC Algorithm, see the document 53*0Sstevel@tonic-gate * titled "A Painless Guide to CRC Error Detection Algorithms" by Ross 54*0Sstevel@tonic-gate * Williams (ross@guest.adelaide.edu.au.). This document is likely to be in 55*0Sstevel@tonic-gate * "ftp.adelaide.edu.au/pub/rocksoft". 56*0Sstevel@tonic-gate * 57*0Sstevel@tonic-gate * Note: Rocksoft is a trademark of Rocksoft Pty Ltd, Adelaide, Australia. 58*0Sstevel@tonic-gate * 59*0Sstevel@tonic-gate * 60*0Sstevel@tonic-gate * 61*0Sstevel@tonic-gate * How to Use This Package 62*0Sstevel@tonic-gate * ----------------------- 63*0Sstevel@tonic-gate * Step 1: Declare a variable of type cm_t. Declare another variable 64*0Sstevel@tonic-gate * (p_cm say) of type p_cm_t and initialize it to point to the first 65*0Sstevel@tonic-gate * variable (e.g. p_cm_t p_cm = &cm_t). 66*0Sstevel@tonic-gate * 67*0Sstevel@tonic-gate * Step 2: Assign values to the parameter fields of the structure. 68*0Sstevel@tonic-gate * If you don't know what to assign, see the document cited earlier. 69*0Sstevel@tonic-gate * For example: 70*0Sstevel@tonic-gate * p_cm->cm_width = 16; 71*0Sstevel@tonic-gate * p_cm->cm_poly = 0x8005L; 72*0Sstevel@tonic-gate * p_cm->cm_init = 0L; 73*0Sstevel@tonic-gate * p_cm->cm_refin = TRUE; 74*0Sstevel@tonic-gate * p_cm->cm_refot = TRUE; 75*0Sstevel@tonic-gate * p_cm->cm_xorot = 0L; 76*0Sstevel@tonic-gate * Note: Poly is specified without its top bit (18005 becomes 8005). 77*0Sstevel@tonic-gate * Note: Width is one bit less than the raw poly width. 78*0Sstevel@tonic-gate * 79*0Sstevel@tonic-gate * Step 3: Initialize the instance with a call cm_ini(p_cm); 80*0Sstevel@tonic-gate * 81*0Sstevel@tonic-gate * Step 4: Process zero or more message bytes by placing zero or more 82*0Sstevel@tonic-gate * successive calls to cm_nxt. Example: cm_nxt(p_cm,ch); 83*0Sstevel@tonic-gate * 84*0Sstevel@tonic-gate * Step 5: Extract the CRC value at any time by calling crc = cm_crc(p_cm); 85*0Sstevel@tonic-gate * If the CRC is a 16-bit value, it will be in the bottom 16 bits. 86*0Sstevel@tonic-gate * 87*0Sstevel@tonic-gate * 88*0Sstevel@tonic-gate * 89*0Sstevel@tonic-gate * Design Notes 90*0Sstevel@tonic-gate * ------------ 91*0Sstevel@tonic-gate * PORTABILITY: This package has been coded very conservatively so that 92*0Sstevel@tonic-gate * it will run on as many machines as possible. For example, all external 93*0Sstevel@tonic-gate * identifiers have been restricted to 6 characters and all internal ones to 94*0Sstevel@tonic-gate * 8 characters. The prefix cm (for Crc Model) is used as an attempt to avoid 95*0Sstevel@tonic-gate * namespace collisions. This package is endian independent. 96*0Sstevel@tonic-gate * 97*0Sstevel@tonic-gate * EFFICIENCY: This package (and its interface) is not designed for 98*0Sstevel@tonic-gate * speed. The purpose of this package is to act as a well-defined reference 99*0Sstevel@tonic-gate * model for the specification of CRC algorithms. If you want speed, cook up 100*0Sstevel@tonic-gate * a specific table-driven implementation as described in the document cited 101*0Sstevel@tonic-gate * above. This package is designed for validation only; if you have found or 102*0Sstevel@tonic-gate * implemented a CRC algorithm and wish to describe it as a set of parameters 103*0Sstevel@tonic-gate * to the Rocksoft^tm Model CRC Algorithm, your CRC algorithm implementation 104*0Sstevel@tonic-gate * should behave identically to this package under those parameters. 105*0Sstevel@tonic-gate * 106*0Sstevel@tonic-gate */ 107*0Sstevel@tonic-gate 108*0Sstevel@tonic-gate 109*0Sstevel@tonic-gate /* The following definitions are extracted from my style header file which */ 110*0Sstevel@tonic-gate /* would be cumbersome to distribute with this package. The DONE_STYLE is the */ 111*0Sstevel@tonic-gate /* idempotence symbol used in my style header file. */ 112*0Sstevel@tonic-gate 113*0Sstevel@tonic-gate #ifndef DONE_STYLE 114*0Sstevel@tonic-gate 115*0Sstevel@tonic-gate typedef unsigned bool; 116*0Sstevel@tonic-gate typedef unsigned char *p_ubyte_; 117*0Sstevel@tonic-gate 118*0Sstevel@tonic-gate #ifndef TRUE 119*0Sstevel@tonic-gate #define FALSE 0 120*0Sstevel@tonic-gate #define TRUE 1 121*0Sstevel@tonic-gate #endif 122*0Sstevel@tonic-gate 123*0Sstevel@tonic-gate /* Change to the second definition if you don't have prototypes. */ 124*0Sstevel@tonic-gate #define P_(A) A 125*0Sstevel@tonic-gate /* #define P_(A) () */ 126*0Sstevel@tonic-gate 127*0Sstevel@tonic-gate /* Uncomment this definition if you don't have void. */ 128*0Sstevel@tonic-gate /* typedef int void; */ 129*0Sstevel@tonic-gate 130*0Sstevel@tonic-gate #endif 131*0Sstevel@tonic-gate 132*0Sstevel@tonic-gate /* CRC Model Abstract Type */ 133*0Sstevel@tonic-gate /* ----------------------- */ 134*0Sstevel@tonic-gate /* The following type stores the context of an executing instance of the */ 135*0Sstevel@tonic-gate /* model algorithm. Most of the fields are model parameters which must be */ 136*0Sstevel@tonic-gate /* set before the first initializing call to cm_ini. */ 137*0Sstevel@tonic-gate typedef struct 138*0Sstevel@tonic-gate { 139*0Sstevel@tonic-gate int cm_width; /* Parameter: Width in bits [8,32]. */ 140*0Sstevel@tonic-gate uint32_t cm_poly; /* Parameter: The algorithm's polynomial. */ 141*0Sstevel@tonic-gate uint32_t cm_init; /* Parameter: Initial register value. */ 142*0Sstevel@tonic-gate bool cm_refin; /* Parameter: Reflect input bytes? */ 143*0Sstevel@tonic-gate bool cm_refot; /* Parameter: Reflect output CRC? */ 144*0Sstevel@tonic-gate uint32_t cm_xorot; /* Parameter: XOR this to output CRC. */ 145*0Sstevel@tonic-gate 146*0Sstevel@tonic-gate uint32_t cm_reg; /* Context: Context during execution. */ 147*0Sstevel@tonic-gate } cm_t; 148*0Sstevel@tonic-gate typedef cm_t *p_cm_t; 149*0Sstevel@tonic-gate 150*0Sstevel@tonic-gate /* Functions That Implement The Model */ 151*0Sstevel@tonic-gate /* ---------------------------------- */ 152*0Sstevel@tonic-gate /* The following functions animate the cm_t abstraction. */ 153*0Sstevel@tonic-gate 154*0Sstevel@tonic-gate void cm_ini P_((p_cm_t p_cm)); 155*0Sstevel@tonic-gate /* Initializes the argument CRC model instance. */ 156*0Sstevel@tonic-gate /* All parameter fields must be set before calling this. */ 157*0Sstevel@tonic-gate 158*0Sstevel@tonic-gate void cm_nxt P_((p_cm_t p_cm, int ch)); 159*0Sstevel@tonic-gate /* Processes a single message byte [0,255]. */ 160*0Sstevel@tonic-gate 161*0Sstevel@tonic-gate void cm_blk P_((p_cm_t p_cm, p_ubyte_ blk_adr, uint32_t blk_len)); 162*0Sstevel@tonic-gate /* Processes a block of message bytes. */ 163*0Sstevel@tonic-gate 164*0Sstevel@tonic-gate uint32_t cm_crc P_((p_cm_t p_cm)); 165*0Sstevel@tonic-gate /* Returns the CRC value for the message bytes processed so far. */ 166*0Sstevel@tonic-gate 167*0Sstevel@tonic-gate /* Functions For Table Calculation */ 168*0Sstevel@tonic-gate /* ------------------------------- */ 169*0Sstevel@tonic-gate /* The following function can be used to calculate a CRC lookup table. */ 170*0Sstevel@tonic-gate /* It can also be used at run-time to create or check static tables. */ 171*0Sstevel@tonic-gate 172*0Sstevel@tonic-gate uint32_t cm_tab P_((p_cm_t p_cm, int index)); 173*0Sstevel@tonic-gate /* Returns the i'th entry for the lookup table for the specified algorithm. */ 174*0Sstevel@tonic-gate /* The function examines the fields cm_width, cm_poly, cm_refin, and the */ 175*0Sstevel@tonic-gate /* argument table index in the range [0,255] and returns the table entry in */ 176*0Sstevel@tonic-gate /* the bottom cm_width bytes of the return value. */ 177*0Sstevel@tonic-gate 178*0Sstevel@tonic-gate #ifdef __cplusplus 179*0Sstevel@tonic-gate } 180*0Sstevel@tonic-gate #endif 181*0Sstevel@tonic-gate 182*0Sstevel@tonic-gate #endif /* _CRCMODEL_H */ 183