diff options
Diffstat (limited to 'util/libreboot-utils/lib/mkhtemp.c')
| -rw-r--r-- | util/libreboot-utils/lib/mkhtemp.c | 53 |
1 files changed, 12 insertions, 41 deletions
diff --git a/util/libreboot-utils/lib/mkhtemp.c b/util/libreboot-utils/lib/mkhtemp.c index 2fb2f01a..191d657c 100644 --- a/util/libreboot-utils/lib/mkhtemp.c +++ b/util/libreboot-utils/lib/mkhtemp.c @@ -886,53 +886,30 @@ err: int mkhtemp_fill_random(char *p, size_t xc) { - size_t chx = 0; - int rand_failures = 0; - - size_t r; - - int saved_rand_error = 0; static char ch[] = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"; + size_t chx = 0; + size_t r; + /* clamp rand to prevent modulo bias - * (reduced risk of entropy leak) */ size_t limit = ((size_t)-1) - (((size_t)-1) % (sizeof(ch) - 1)); - int saved_errno = errno; - if (p == NULL) { - errno = EFAULT; - goto err_mkhtemp_fill_random; - } + if (if_err(p == NULL, EFAULT)) + return -1; for (chx = 0; chx < xc; chx++) { - do { - saved_rand_error = errno; - rand_failures = 0; retry_rand: - errno = 0; - - /* on bsd: uses arc4random - on linux: uses getrandom - on OLD linux: /dev/urandom - on old/other unix: /dev/urandom - */ - r = rlong(); - - if (errno > 0) { - if (++rand_failures <= 8) - goto retry_rand; - - goto err_mkhtemp_fill_random; - } - - rand_failures = 0; - errno = saved_rand_error; - - } while (r >= limit); + /* on bsd: uses arc4random + on linux: uses getrandom + *never returns error* + */ + r = rlong(); /* always returns successful */ + if (r >= limit) + goto retry_rand; p[chx] = ch[r % (sizeof(ch) - 1)]; } @@ -940,12 +917,6 @@ retry_rand: errno = saved_errno; return 0; -err_mkhtemp_fill_random: - - if (errno == saved_errno) - errno = ECANCELED; - - return -1; } /* WARNING: **ONCE** per file. |
