src/libs/compat/freebsd_network/fbsd_ether.c

   1 /*-
   2  * Copyright (c) 1982, 1989, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 4. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  *      @(#)if_ethersubr.c      8.1 (Berkeley) 6/10/93
  30  * $FreeBSD: src/sys/net/if_ethersubr.c,v 1.193.2.12 2006/08/28 02:54:14 thompsa Exp $
  31  */
  32 #include <stdio.h>
  33 #include <sys/types.h>
  34 #include <net/ethernet.h>
  35
  36 #if 0
  37 /*
  38  * This is for reference.  We have a table-driven version
  39  * of the little-endian crc32 generator, which is faster
  40  * than the double-loop.
  41  */
  42 uint32_t
  43 ether_crc32_le(const uint8_t *buf, size_t len)
  44 {
  45         size_t i;
  46         uint32_t crc;
  47         int bit;
  48         uint8_t data;
  49
  50         crc = 0xffffffff;       /* initial value */
  51
  52         for (i = 0; i < len; i++) {
  53                 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1)
  54                         carry = (crc ^ data) & 1;
  55                         crc >>= 1;
  56                         if (carry)
  57                                 crc = (crc ^ ETHER_CRC_POLY_LE);
  58         }
  59
  60         return (crc);
  61 }
  62 #else
  63 uint32_t
  64 ether_crc32_le(const uint8_t *buf, size_t len)
  65 {
  66         static const uint32_t crctab[] = {
  67                 0x00000000, 0x1db71064, 0x3b6e20c8, 0x26d930ac,
  68                 0x76dc4190, 0x6b6b51f4, 0x4db26158, 0x5005713c,
  69                 0xedb88320, 0xf00f9344, 0xd6d6a3e8, 0xcb61b38c,
  70                 0x9b64c2b0, 0x86d3d2d4, 0xa00ae278, 0xbdbdf21c
  71         };
  72         size_t i;
  73         uint32_t crc;
  74
  75         crc = 0xffffffff;       /* initial value */
  76
  77         for (i = 0; i < len; i++) {
  78                 crc ^= buf[i];
  79                 crc = (crc >> 4) ^ crctab[crc & 0xf];
  80                 crc = (crc >> 4) ^ crctab[crc & 0xf];
  81         }
  82
  83         return (crc);
  84 }
  85 #endif
  86
  87 uint32_t
  88 ether_crc32_be(const uint8_t *buf, size_t len)
  89 {
  90         size_t i;
  91         uint32_t crc, carry;
  92         int bit;
  93         uint8_t data;
  94
  95         crc = 0xffffffff;       /* initial value */
  96
  97         for (i = 0; i < len; i++) {
  98                 for (data = *buf++, bit = 0; bit < 8; bit++, data >>= 1) {
  99                         carry = ((crc & 0x80000000) ? 1 : 0) ^ (data & 0x01);
 100                         crc <<= 1;
 101                         if (carry)
 102                                 crc = (crc ^ ETHER_CRC_POLY_BE) | carry;
 103                 }
 104         }
 105
 106         return (crc);
 107 }
 108
 109 char *
 110 ether_sprintf(const u_char *ap)
 111 {
 112         static char etherbuf[18];
 113         snprintf(etherbuf, sizeof (etherbuf),
 114                 "%02x:%02x:%02x:%02x:%02x:%02x",
 115                 (unsigned)ap[0], (unsigned)ap[1], (unsigned)ap[2],
 116                 (unsigned)ap[3], (unsigned)ap[4], (unsigned)ap[5]);
 117         return (etherbuf);
 118 }