sys/netinet/sctp_crc32.c

/*	$KAME: sctp_crc32.c,v 1.12 2005/03/06 16:04:17 itojun Exp $	*/
/*	$NetBSD: sctp_crc32.c,v 1.2 2016/08/12 19:08:54 jdolecek Exp $ */

/*
 * Copyright (c) 2001, 2002, 2003, 2004 Cisco Systems, Inc.
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by Cisco Systems, Inc.
 * 4. Neither the name of the project nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY CISCO SYSTEMS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL CISCO SYSTEMS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: sctp_crc32.c,v 1.2 2016/08/12 19:08:54 jdolecek Exp $");

#ifdef _KERNEL_OPT
#include "opt_sctp.h"
#endif /* _KERNEL_OPT */

#include <sys/param.h>
#include <netinet/sctp_crc32.h>

#ifndef SCTP_USE_ADLER32

#define SCTP_CRC32C_POLY 0x1EDC6F41
#define SCTP_CRC32C(c, d) (c = ((c) >> 8) ^ sctp_crc_c[((c) ^ (d)) & 0xFF])

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/* Copyright 2001, D. Otis.  Use this program, code or tables    */
/* extracted from it, as desired without restriction.            */
/*                                                               */
/* 32 Bit Reflected CRC table generation for SCTP.               */
/* To accommodate serial byte data being shifted out least       */
/* significant bit first, the table's 32 bit words are reflected */
/* which flips both byte and bit MS and LS positions.  The CRC   */
/* is calculated MS bits first from the perspective of the serial*/
/* stream.  The x^32 term is implied and the x^0 term may also   */
/* be shown as +1.  The polynomial code used is 0x1EDC6F41.      */
/* Castagnoli93                                                  */
/* x^32+x^28+x^27+x^26+x^25+x^23+x^22+x^20+x^19+x^18+x^14+x^13+  */
/* x^11+x^10+x^9+x^8+x^6+x^0                                     */
/* Guy Castagnoli Stefan Braeuer and Martin Herrman              */
/* "Optimization of Cyclic Redundancy-Check Codes                */
/* with 24 and 32 Parity Bits",                                  */
/* IEEE Transactions on Communications, Vol.41, No.6, June 1993  */
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

const unsigned long  sctp_crc_c[256] = {
	0x00000000L, 0xF26B8303L, 0xE13B70F7L, 0x1350F3F4L,
	0xC79A971FL, 0x35F1141CL, 0x26A1E7E8L, 0xD4CA64EBL,
	0x8AD958CFL, 0x78B2DBCCL, 0x6BE22838L, 0x9989AB3BL,
	0x4D43CFD0L, 0xBF284CD3L, 0xAC78BF27L, 0x5E133C24L,
	0x105EC76FL, 0xE235446CL, 0xF165B798L, 0x030E349BL,
	0xD7C45070L, 0x25AFD373L, 0x36FF2087L, 0xC494A384L,
	0x9A879FA0L, 0x68EC1CA3L, 0x7BBCEF57L, 0x89D76C54L,
	0x5D1D08BFL, 0xAF768BBCL, 0xBC267848L, 0x4E4DFB4BL,
	0x20BD8EDEL, 0xD2D60DDDL, 0xC186FE29L, 0x33ED7D2AL,
	0xE72719C1L, 0x154C9AC2L, 0x061C6936L, 0xF477EA35L,
	0xAA64D611L, 0x580F5512L, 0x4B5FA6E6L, 0xB93425E5L,
	0x6DFE410EL, 0x9F95C20DL, 0x8CC531F9L, 0x7EAEB2FAL,
	0x30E349B1L, 0xC288CAB2L, 0xD1D83946L, 0x23B3BA45L,
	0xF779DEAEL, 0x05125DADL, 0x1642AE59L, 0xE4292D5AL,
	0xBA3A117EL, 0x4851927DL, 0x5B016189L, 0xA96AE28AL,
	0x7DA08661L, 0x8FCB0562L, 0x9C9BF696L, 0x6EF07595L,
	0x417B1DBCL, 0xB3109EBFL, 0xA0406D4BL, 0x522BEE48L,
	0x86E18AA3L, 0x748A09A0L, 0x67DAFA54L, 0x95B17957L,
	0xCBA24573L, 0x39C9C670L, 0x2A993584L, 0xD8F2B687L,
	0x0C38D26CL, 0xFE53516FL, 0xED03A29BL, 0x1F682198L,
	0x5125DAD3L, 0xA34E59D0L, 0xB01EAA24L, 0x42752927L,
	0x96BF4DCCL, 0x64D4CECFL, 0x77843D3BL, 0x85EFBE38L,
	0xDBFC821CL, 0x2997011FL, 0x3AC7F2EBL, 0xC8AC71E8L,
	0x1C661503L, 0xEE0D9600L, 0xFD5D65F4L, 0x0F36E6F7L,
	0x61C69362L, 0x93AD1061L, 0x80FDE395L, 0x72966096L,
	0xA65C047DL, 0x5437877EL, 0x4767748AL, 0xB50CF789L,
	0xEB1FCBADL, 0x197448AEL, 0x0A24BB5AL, 0xF84F3859L,
	0x2C855CB2L, 0xDEEEDFB1L, 0xCDBE2C45L, 0x3FD5AF46L,
	0x7198540DL, 0x83F3D70EL, 0x90A324FAL, 0x62C8A7F9L,
	0xB602C312L, 0x44694011L, 0x5739B3E5L, 0xA55230E6L,
	0xFB410CC2L, 0x092A8FC1L, 0x1A7A7C35L, 0xE811FF36L,
	0x3CDB9BDDL, 0xCEB018DEL, 0xDDE0EB2AL, 0x2F8B6829L,
	0x82F63B78L, 0x709DB87BL, 0x63CD4B8FL, 0x91A6C88CL,
	0x456CAC67L, 0xB7072F64L, 0xA457DC90L, 0x563C5F93L,
	0x082F63B7L, 0xFA44E0B4L, 0xE9141340L, 0x1B7F9043L,
	0xCFB5F4A8L, 0x3DDE77ABL, 0x2E8E845FL, 0xDCE5075CL,
	0x92A8FC17L, 0x60C37F14L, 0x73938CE0L, 0x81F80FE3L,
	0x55326B08L, 0xA759E80BL, 0xB4091BFFL, 0x466298FCL,
	0x1871A4D8L, 0xEA1A27DBL, 0xF94AD42FL, 0x0B21572CL,
	0xDFEB33C7L, 0x2D80B0C4L, 0x3ED04330L, 0xCCBBC033L,
	0xA24BB5A6L, 0x502036A5L, 0x4370C551L, 0xB11B4652L,
	0x65D122B9L, 0x97BAA1BAL, 0x84EA524EL, 0x7681D14DL,
	0x2892ED69L, 0xDAF96E6AL, 0xC9A99D9EL, 0x3BC21E9DL,
	0xEF087A76L, 0x1D63F975L, 0x0E330A81L, 0xFC588982L,
	0xB21572C9L, 0x407EF1CAL, 0x532E023EL, 0xA145813DL,
	0x758FE5D6L, 0x87E466D5L, 0x94B49521L, 0x66DF1622L,
	0x38CC2A06L, 0xCAA7A905L, 0xD9F75AF1L, 0x2B9CD9F2L,
	0xFF56BD19L, 0x0D3D3E1AL, 0x1E6DCDEEL, 0xEC064EEDL,
	0xC38D26C4L, 0x31E6A5C7L, 0x22B65633L, 0xD0DDD530L,
	0x0417B1DBL, 0xF67C32D8L, 0xE52CC12CL, 0x1747422FL,
	0x49547E0BL, 0xBB3FFD08L, 0xA86F0EFCL, 0x5A048DFFL,
	0x8ECEE914L, 0x7CA56A17L, 0x6FF599E3L, 0x9D9E1AE0L,
	0xD3D3E1ABL, 0x21B862A8L, 0x32E8915CL, 0xC083125FL,
	0x144976B4L, 0xE622F5B7L, 0xF5720643L, 0x07198540L,
	0x590AB964L, 0xAB613A67L, 0xB831C993L, 0x4A5A4A90L,
	0x9E902E7BL, 0x6CFBAD78L, 0x7FAB5E8CL, 0x8DC0DD8FL,
	0xE330A81AL, 0x115B2B19L, 0x020BD8EDL, 0xF0605BEEL,
	0x24AA3F05L, 0xD6C1BC06L, 0xC5914FF2L, 0x37FACCF1L,
	0x69E9F0D5L, 0x9B8273D6L, 0x88D28022L, 0x7AB90321L,
	0xAE7367CAL, 0x5C18E4C9L, 0x4F48173DL, 0xBD23943EL,
	0xF36E6F75L, 0x0105EC76L, 0x12551F82L, 0xE03E9C81L,
	0x34F4F86AL, 0xC69F7B69L, 0xD5CF889DL, 0x27A40B9EL,
	0x79B737BAL, 0x8BDCB4B9L, 0x988C474DL, 0x6AE7C44EL,
	0xBE2DA0A5L, 0x4C4623A6L, 0x5F16D052L, 0xAD7D5351L,
};

u_int32_t
update_crc32(u_int32_t crc32c,
	     unsigned char *buffer,
	     unsigned int length)
{
	unsigned int i;

	for (i = 0; i < length; i++) {
		SCTP_CRC32C(crc32c, buffer[i]);
	}
	return (crc32c);
}


u_int32_t
sctp_csum_finalize(u_int32_t crc32c)
{
	u_int32_t result;
#if BYTE_ORDER == BIG_ENDIAN
	u_int8_t byte0, byte1, byte2, byte3;
#endif
	/* Complement the result */
	result = ~crc32c;
#if BYTE_ORDER == BIG_ENDIAN
	/*
	 * For BIG-ENDIAN.. aka Motorola byte order the result is in
	 * little-endian form. So we must manually swap the bytes. Then
	 * we can call htonl() which does nothing...
	 */
	byte0 = result & 0x000000ff;
	byte1 = (result >> 8) & 0x000000ff;
	byte2 = (result >> 16) & 0x000000ff;
	byte3 = (result >> 24) & 0x000000ff;
	result = ((byte0 << 24) | (byte1 << 16) | (byte2 << 8) | byte3);
	crc32c = htonl(result);
#else
	/*
	 * For INTEL platforms the result comes out in network order.
	 * No htonl is required or the swap above. So we optimize out
	 * both the htonl and the manual swap above.
	 */
	crc32c = result;
#endif
	return (crc32c);
}

#endif