LXR toybox/toys/other/mcookie.c

   1/* mcookie - generate a 128-bit random number (used for X "magic cookies")
   2 *
   3 * Copyright 2019 AD Isaac Dunham <ibid.ag@gmail.com>
   4 *
   5 * No standard.
   6 *
   7 * -f and -m are not supported: md5sums of arbitrary files are not a good
   8 * source of entropy, just ask the system for 128 bits and print it.
   9
  10USE_MCOOKIE(NEWTOY(mcookie, "v(verbose)V(version)", TOYFLAG_USR|TOYFLAG_BIN))
  11
  12config MCOOKIE
  13  bool "mcookie"
  14  default y
  15  help
  16    usage: mcookie [-vV]
  17
  18    Generate a 128-bit strong random number.
  19
  20    -v  show entropy source (verbose)
  21    -V  show version
  22*/
  23
  24#define FOR_mcookie
  25#include "toys.h"
  26
  27void mcookie_main(void)
  28{
  29  long long *ll = (void *)toybuf;
  30
  31  if (FLAG(V)) return (void)puts("mcookie from toybox");
  32  xgetrandom(toybuf, 16, 0);
  33  if (FLAG(v)) fputs("Got 16 bytes from xgetrandom()\n", stderr);
  34  xprintf("%016llx%06llx\n", ll[0], ll[1]);
  35}
  36