usr/src/test/libc-tests/tests/random/getentropy.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 getentropy(3C)
  18  */
  19
  20 #include <unistd.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 errbuf[512];
  31         uint8_t buf[128];
  32
  33         ret = getentropy(buf, sizeof (buf));
  34         assert(ret == 0);
  35
  36         /* Max buffer is 256 bytes, verify if we go larger, we error */
  37         ret = getentropy(errbuf, sizeof (errbuf));
  38         assert(ret == -1);
  39         assert(errno == EIO);
  40
  41         ret = getentropy(errbuf, 257);
  42         assert(ret == -1);
  43         assert(errno == EIO);
  44
  45         ret = getentropy(errbuf, 256);
  46         assert(ret == 0);
  47
  48         ret = getentropy(errbuf, 0);
  49         assert(ret == 0);
  50
  51         /* Bad buffers */
  52         ret = getentropy(NULL, sizeof (buf));
  53         assert(ret == -1);
  54         assert(errno == EFAULT);
  55
  56         /* Jump through a hoop to know we'll always have a bad address */
  57         addr = mmap(NULL, 4096, PROT_READ, MAP_PRIVATE | MAP_ANON, -1, 0);
  58         assert(addr != MAP_FAILED);
  59         ret = munmap(addr, 4096);
  60         assert(ret == 0);
  61         ret = getentropy(addr, sizeof (buf));
  62         assert(ret == -1);
  63         assert(errno == EFAULT);
  64
  65         return (0);
  66 }