Hi
On 12/18/20 10:28 AM, matthias....@kernel.org wrote:
From: Matthias Brugger <mbrug...@suse.com>
When calculating a random UUID we use a weak seed.
Use a RNG device if present to increase entropy.
Signed-off-by: Matthias Brugger <mbrug...@suse.com>
---
Changes in v3:
- use IS_ENABLED instead of #if
- use 4 byte for entropy
Changes in v2:
- fix dm_rng_read() parameters
- add missing include
lib/uuid.c | 21 ++++++++++++++++++---
1 file changed, 18 insertions(+), 3 deletions(-)
diff --git a/lib/uuid.c b/lib/uuid.c
index e62d5ca264..23af2b4800 100644
--- a/lib/uuid.c
+++ b/lib/uuid.c
@@ -15,6 +15,8 @@
#include <asm/io.h>
#include <part_efi.h>
#include <malloc.h>
+#include <dm/uclass.h>
+#include <rng.h>
/*
* UUID - Universally Unique IDentifier - 128 bits unique number.
@@ -249,9 +251,22 @@ void gen_rand_uuid(unsigned char *uuid_bin)
{
u32 ptr[4];
struct uuid *uuid = (struct uuid *)ptr;
- int i;
-
- srand(get_ticks() + rand());
+ int i, ret;
+ struct udevice *devp;
+ u32 randv = 0;
+
+ if (IS_ENABLED(CONFIG_DM_RNG)) {
+ ret = uclass_get_device(UCLASS_RNG, 0, &devp);
+ if (ret) {
For information, as this patch already merged
here we need to test if ret == 0:
+ if (!ret) {
I push a patch to correct this test:
"lib: uuid: fix the test on RNG device presence"
http://patchwork.ozlabs.org/project/uboot/patch/20211022170544.1.Ib218a8a747f99cab44c3fac6af649f17f003b2e2@changeid/
+ ret = dm_rng_read(devp, &randv, sizeof(randv));
+ if (ret < 0)
+ randv = 0;
+ }
+ }
+ if (randv)
+ srand(randv);
+ else
+ srand(get_ticks() + rand());
/* Set all fields randomly */
for (i = 0; i < 4; i++)
Regards
Patrick
