155682Smarkm/* 2233294Sstas * Copyright (c) 1997 - 2000 Kungliga Tekniska H��gskolan 3233294Sstas * (Royal Institute of Technology, Stockholm, Sweden). 4233294Sstas * All rights reserved. 555682Smarkm * 6233294Sstas * Redistribution and use in source and binary forms, with or without 7233294Sstas * modification, are permitted provided that the following conditions 8233294Sstas * are met: 955682Smarkm * 10233294Sstas * 1. Redistributions of source code must retain the above copyright 11233294Sstas * notice, this list of conditions and the following disclaimer. 1255682Smarkm * 13233294Sstas * 2. Redistributions in binary form must reproduce the above copyright 14233294Sstas * notice, this list of conditions and the following disclaimer in the 15233294Sstas * documentation and/or other materials provided with the distribution. 1655682Smarkm * 17233294Sstas * 3. Neither the name of the Institute nor the names of its contributors 18233294Sstas * may be used to endorse or promote products derived from this software 19233294Sstas * without specific prior written permission. 2055682Smarkm * 21233294Sstas * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND 22233294Sstas * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23233294Sstas * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24233294Sstas * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE 25233294Sstas * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26233294Sstas * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27233294Sstas * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28233294Sstas * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29233294Sstas * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30233294Sstas * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31233294Sstas * SUCH DAMAGE. 3255682Smarkm */ 3355682Smarkm 3455682Smarkm#include "krb5_locl.h" 3555682Smarkm 3655682Smarkmstatic u_long table[256]; 3755682Smarkm 3855682Smarkm#define CRC_GEN 0xEDB88320L 3955682Smarkm 4055682Smarkmvoid 4155682Smarkm_krb5_crc_init_table(void) 4255682Smarkm{ 4355682Smarkm static int flag = 0; 4455682Smarkm unsigned long crc, poly; 45233294Sstas unsigned int i, j; 46233294Sstas 4755682Smarkm if(flag) return; 4855682Smarkm poly = CRC_GEN; 4955682Smarkm for (i = 0; i < 256; i++) { 5055682Smarkm crc = i; 5155682Smarkm for (j = 8; j > 0; j--) { 5255682Smarkm if (crc & 1) { 5355682Smarkm crc = (crc >> 1) ^ poly; 5455682Smarkm } else { 5555682Smarkm crc >>= 1; 5655682Smarkm } 5755682Smarkm } 5855682Smarkm table[i] = crc; 5955682Smarkm } 6055682Smarkm flag = 1; 6155682Smarkm} 6255682Smarkm 63178825Sdfruint32_t 64178825Sdfr_krb5_crc_update (const char *p, size_t len, uint32_t res) 6555682Smarkm{ 6655682Smarkm while (len--) 6755682Smarkm res = table[(res ^ *p++) & 0xFF] ^ (res >> 8); 6855682Smarkm return res & 0xFFFFFFFF; 6955682Smarkm} 70