usr/src/test/libc-tests/tests/random/getrandom.c

   1 /*
   2  * This file and its contents are supplied under the terms of the
   3  * Common Development and Distribution License ("CDDL"), version 1.0.
   4  * You may only use this file in accordance with the terms of version
   5  * 1.0 of the CDDL.
   6  *
   7  * A full copy of the text of the CDDL should have accompanied this
   8  * source.  A copy of the CDDL is also available via the Internet at
   9  * http://www.illumos.org/license/CDDL.
  10  */
  11
  12 /*
  13  * Copyright (c) 2015, Joyent, Inc.
  14  */
  15
  16 /*
  17  * Test getrandom(2)
  18  */
  19
  20 #include <sys/random.h>
  21 #include <sys/mman.h>
  22 #include <assert.h>
  23 #include <errno.h>
  24
  25 int
  26 main(void)
  27 {
  28         int ret;
  29         void *addr;
  30         uint8_t buf[32];
  31         uint8_t bigbuf[4096];
  32
  33         /* Go through flags values, start with invalid */
  34         ret = getrandom(buf, sizeof (buf), 42);
  35         assert(ret == -1);
  36         assert(errno == EINVAL);
  37
  38         ret = getrandom(buf, sizeof (buf), 0);
  39         assert(ret >= 0);
  40
  41         ret = getrandom(buf, sizeof (buf), GRND_NONBLOCK);
  42         assert(ret >= 0);
  43
  44         ret = getrandom(buf, sizeof (buf), GRND_RANDOM);
  45         assert(ret >= 0);
  46
  47         ret = getrandom(buf, sizeof (buf), GRND_RANDOM | GRND_NONBLOCK);
  48         assert(ret >= 0);
  49
  50         ret = getrandom(buf, sizeof (buf), (GRND_RANDOM | GRND_NONBLOCK) << 1);
  51         assert(ret == -1);
  52         assert(errno == EINVAL);
  53
  54         /* Bad buffer addresses, eg. EFAULT */
  55         ret = getrandom(NULL, sizeof (buf), 0);
  56         assert(ret == -1);
  57         assert(errno == EFAULT);
  58
  59         ret = getrandom(NULL, sizeof (buf), GRND_RANDOM);
  60         assert(ret == -1);
  61         assert(errno == EFAULT);
  62
  63         /* Jump through a hoop to know we'll always have a bad address */
  64         addr = mmap(NULL, 4096, PROT_READ, MAP_PRIVATE | MAP_ANON, -1, 0);
  65         assert(addr != MAP_FAILED);
  66         ret = munmap(addr, 4096);
  67         assert(ret == 0);
  68         ret = getrandom(addr, sizeof (buf), 0);
  69         assert(ret == -1);
  70         assert(errno == EFAULT);
  71         ret = getrandom(addr, sizeof (buf), GRND_RANDOM);
  72         assert(ret == -1);
  73         assert(errno == EFAULT);
  74
  75         /* Verify that we get rounded down on a getrandom of /dev/random */
  76         ret = getrandom(bigbuf, sizeof (buf), GRND_RANDOM);
  77         assert(ret >= 0 && ret < sizeof (bigbuf));
  78
  79         /* Do a few simple sets where we know we should get data */
  80         ret = getrandom(buf, sizeof (buf), 0);
  81         assert(ret == sizeof (buf));
  82         ret = getrandom(buf, sizeof (buf), GRND_RANDOM);
  83         assert(ret == sizeof (buf));
  84
  85         return (0);
  86 }