diff options
Diffstat (limited to 'util/libreboot-utils/lib/rand.c')
| -rw-r--r-- | util/libreboot-utils/lib/rand.c | 60 |
1 files changed, 9 insertions, 51 deletions
diff --git a/util/libreboot-utils/lib/rand.c b/util/libreboot-utils/lib/rand.c index 58cb211e..3155eec3 100644 --- a/util/libreboot-utils/lib/rand.c +++ b/util/libreboot-utils/lib/rand.c @@ -72,62 +72,20 @@ * or your program dies. */ -#define MAX_ALLOC (2 << 16) - -int -win_lottery(void) /* are u lucky? */ +void * +rmalloc(size_t *rval) { - size_t size = rsize(); - size_t size2 = rsize(); - char *s = NULL; - - if (size && - size == size2 && - size <= MAX_ALLOC << 1) { - - if (!memcmp(s = mkrbuf(size << 1), - s + size, size)) - size2 = 1; /* winner! */ - else - size2 = 0; - } else { - return 0; - } - - free_if_null(&s); - return (int)size2; + return if_err(rval == NULL, EFAULT) ? + NULL : mkrstr(*rval = rsize(BUFSIZ)); } size_t -rsize(void) -{ - size_t rval = 0; - - /* clamp rand to prevent modulo bias */ - size_t limit = SIZE_MAX - (SIZE_MAX % MAX_ALLOC); - - do { - rset(&rval, sizeof(rval)); - } while (rval >= limit); - - return rval % MAX_ALLOC; -} - - -void * -rmalloc(size_t *rval) +rsize(size_t n) { - /* clamp rand to prevent modulo bias */ - size_t limit = SIZE_MAX - (SIZE_MAX % MAX_ALLOC); - - if (if_err(rval == NULL, EFAULT)) - return NULL; - - do { - rset(rval, sizeof(*rval)); - } while (*rval >= limit || *rval == 0); + size_t rval = SIZE_MAX; + for (; rval >= SIZE_MAX - (SIZE_MAX % n); rset(&rval, sizeof(rval))); - return mkrstr(*rval %= MAX_ALLOC); + return rval % n; } char * @@ -157,7 +115,7 @@ mkrstr(size_t n) /* emulates spkmodem-decode */ void * mkrbuf(size_t n) { - void *buf; + void *buf = ""; if (n == 0) err_no_cleanup(0, EPERM, "mkrbuf: zero-byte request"); |
