From a118a9b503537894fd9dc4ff021ef3b0635166eb Mon Sep 17 00:00:00 2001
From: Rob Austein <sra@hactrn.net>
Date: Fri, 3 Feb 2017 00:21:02 -0500
Subject: Clean up csprng driver.
---
csprng.c | 23 +++++++++++------------
1 file changed, 11 insertions(+), 12 deletions(-)
diff --git a/csprng.c b/csprng.c
index 7ff6c69..8ba4fa5 100644
--- a/csprng.c
+++ b/csprng.c
@@ -45,35 +45,34 @@
hal_error_t hal_get_random(hal_core_t *core, void *buffer, const size_t length)
{
- uint8_t temp[4], *buf = buffer;
+ uint8_t temp[4], ior = 0, * const buf = buffer;
hal_error_t err;
- size_t i;
if ((err = hal_core_alloc(CSPRNG_NAME, &core)) != HAL_OK)
return err;
- for (i = 0; i < length; i += 4) {
+ for (size_t i = 0; i < length; i += 4) {
const int last = (length - i) < 4;
if (WAIT_FOR_CSPRNG_VALID && (err = hal_io_wait_valid(core)) != HAL_OK)
- goto out;
+ break;
if ((err = hal_io_read(core, CSPRNG_ADDR_RANDOM, (last ? temp : &buf[i]), 4)) != HAL_OK)
- goto out;
+ break;
if (last)
for (; i < length; i++)
buf[i] = temp[i&3];
}
- for (i = 0, buf = buffer; i < length; i++, buf++)
- if (*buf != 0) {
- err = HAL_OK;
- goto out;
- }
- err = HAL_ERROR_CSPRNG_BROKEN;
+ if (err == HAL_OK) {
+ for (size_t i = 0; i < length; i++)
+ ior |= buf[i];
+
+ if (ior == 0 && length > 0)
+ err = HAL_ERROR_CSPRNG_BROKEN;
+ }
-out:
hal_core_free(core);
return err;
}
--
cgit v1.2.3