tests/prng.c

   1 #include <dispatch/dispatch.h>
   2 #include <darwintest.h>
   3 #include <darwintest_utils.h>
   4 #include <sys/random.h>
   5
   6 T_GLOBAL_META(T_META_RUN_CONCURRENTLY(true));
   7
   8 #define BUF_SIZE ((size_t)(1 << 25))
   9 #define BLOCK_SIZE ((size_t)16)
  10
  11 static int
  12 cmp(const void *a, const void *b)
  13 {
  14         return memcmp(a, b, 16);
  15 }
  16
  17 static void
  18 prng_sanitycheck(uint8_t *buf, size_t buf_size)
  19 {
  20         size_t nblocks = buf_size / BLOCK_SIZE;
  21         qsort(buf, nblocks, BLOCK_SIZE, cmp);
  22
  23         for (size_t i = 0; i < nblocks - 1; i += 1) {
  24                 T_QUIET;
  25                 T_ASSERT_NE(memcmp(buf, buf + BLOCK_SIZE, BLOCK_SIZE), 0, "duplicate block");
  26                 buf += BLOCK_SIZE;
  27         }
  28 }
  29
  30 static void
  31 prng_getentropy(void *ctx, size_t i)
  32 {
  33         uint8_t *buf = ((uint8_t *)ctx) + (BUF_SIZE * i);
  34
  35         for (size_t j = 0; j < BUF_SIZE; j += 256) {
  36                 T_QUIET;
  37                 T_ASSERT_POSIX_SUCCESS(getentropy(&buf[j], 256), "getentropy");
  38         }
  39
  40         prng_sanitycheck(buf, BUF_SIZE);
  41 }
  42
  43 static void
  44 prng_devrandom(void *ctx, size_t i)
  45 {
  46         uint8_t *buf = ((uint8_t *)ctx) + (BUF_SIZE * i);
  47
  48         int fd = open("/dev/random", O_RDONLY);
  49         T_QUIET;
  50         T_ASSERT_POSIX_SUCCESS(fd, "open");
  51
  52         size_t n = BUF_SIZE;
  53         while (n > 0) {
  54                 ssize_t m = read(fd, buf, n);
  55                 T_QUIET;
  56                 T_ASSERT_POSIX_SUCCESS(m, "read");
  57
  58                 n -= (size_t)m;
  59                 buf += m;
  60         }
  61
  62         buf = ((uint8_t *)ctx) + (BUF_SIZE * i);
  63         prng_sanitycheck(buf, BUF_SIZE);
  64 }
  65
  66 T_DECL(prng, "prng test")
  67 {
  68         size_t ncpu = (size_t)dt_ncpu();
  69
  70         uint8_t *buf = malloc(BUF_SIZE * ncpu);
  71         T_QUIET;
  72         T_ASSERT_NOTNULL(buf, "malloc");
  73
  74         dispatch_apply_f(ncpu, DISPATCH_APPLY_AUTO, buf, prng_getentropy);
  75
  76         dispatch_apply_f(ncpu, DISPATCH_APPLY_AUTO, buf, prng_devrandom);
  77
  78         prng_sanitycheck(buf, BUF_SIZE * ncpu);
  79
  80         free(buf);
  81 }