tools/gen_eth_addr.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * (C) Copyright 2001
   4  * Murray Jensen <Murray.Jensen@cmst.csiro.au>
   5  */
   6
   7 #include <stdio.h>
   8 #include <stdlib.h>
   9 #include <unistd.h>
  10 #include <time.h>
  11
  12 int
  13 main(int argc, char *argv[])
  14 {
  15     unsigned long ethaddr_low, ethaddr_high;
  16
  17     srand(time(0) + (getpid() << 8));
  18
  19     /*
  20      * setting the 2nd LSB in the most significant byte of
  21      * the address makes it a locally administered ethernet
  22      * address
  23      */
  24     ethaddr_high = (rand() & 0xfeff) | 0x0200;
  25     ethaddr_low = rand();
  26
  27     printf("%02lx:%02lx:%02lx:%02lx:%02lx:%02lx\n",
  28         ethaddr_high >> 8, ethaddr_high & 0xff,
  29         ethaddr_low >> 24, (ethaddr_low >> 16) & 0xff,
  30         (ethaddr_low >> 8) & 0xff, ethaddr_low & 0xff);
  31
  32     return (0);
  33 }