From 92fdad28cfdf078fe34c198ef430933e7b2825a1 Mon Sep 17 00:00:00 2001
From: Matthias Brugger <mbrugger@suse.com>
Date: Fri, 18 Dec 2020 10:28:03 +0100
Subject: [PATCH] lib: uuid: use RNG device if present
When calculating a random UUID we use a weak seed.
Use a RNG device if present to increase entropy.
Signed-off-by: Matthias Brugger <mbrugger@suse.com>
Reviewed-by: Torsten Duwe <duwe@suse.de>
---
lib/uuid.c | 21 ++++++++++++++++++---
1 file changed, 18 insertions(+), 3 deletions(-)
diff --git a/lib/uuid.c b/lib/uuid.c
index 54a93aacc9..5bc68674d0 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) {
+ 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++)
--
2.39.5