tools/gen_eth_addr.c

   1 /*
   2  * (C) Copyright 2001
   3  * Murray Jensen <Murray.Jensen@cmst.csiro.au>
   4  *
   5  * See file CREDITS for list of people who contributed to this
   6  * project.
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation; either version 2 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  21  * MA 02111-1307 USA
  22  */
  23
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <unistd.h>
  27 #include <time.h>
  28
  29 int
  30 main(int argc, char *argv[])
  31 {
  32     unsigned long ethaddr_low, ethaddr_high;
  33
  34     srandom(time(0) | getpid());
  35
  36     /*
  37      * setting the 2nd LSB in the most significant byte of
  38      * the address makes it a locally administered ethernet
  39      * address
  40      */
  41     ethaddr_high = (random() & 0xfeff) | 0x0200;
  42     ethaddr_low = random();
  43
  44     printf("%02lx:%02lx:%02lx:%02lx:%02lx:%02lx\n",
  45         ethaddr_high >> 8, ethaddr_high & 0xff,
  46         ethaddr_low >> 24, (ethaddr_low >> 16) & 0xff,
  47         (ethaddr_low >> 8) & 0xff, ethaddr_low & 0xff);
  48
  49     return (0);
  50 }