On Wed, 16 Dec 2020 11:41:17 +0100
[email protected] wrote:
> From: Matthias Brugger <[email protected]>
>
> When calling srand_mac we use a weak seed dependent on the
> mac address. If present, use a RNG device instead to incerase entropy.
>
> Signed-off-by: Matthias Brugger <[email protected]>
>
> ---
>
> net/net_rand.h | 18 +++++++++++++++++-
> 1 file changed, 17 insertions(+), 1 deletion(-)
>
> diff --git a/net/net_rand.h b/net/net_rand.h
> index 4bf9bd817e..600c3d825e 100644
> --- a/net/net_rand.h
> +++ b/net/net_rand.h
> @@ -10,6 +10,7 @@
> #define __NET_RAND_H__
>
> #include <common.h>
> +#include <rng.h>
>
> /*
> * Return a seed for the PRNG derived from the eth0 MAC address.
> @@ -37,7 +38,22 @@ static inline unsigned int seed_mac(void)
> */
> static inline void srand_mac(void)
> {
> - srand(seed_mac());
> +#if defined(CONFIG_DM_RNG)
> + int ret;
> + struct udevice *devp;
> + u32 randv = 0;
> +
> + ret = uclass_get_device(UCLASS_RNG, 0, &devp);
> + if (ret) {
> + ret = dm_rng_read(dev, randv, sizeof(randv));
Haven't tested this (yet), but shouldn't this be
ret = dm_rng_read(devp, &randv, sizeof(randv));
^ ^ ?
> + if (ret < 0)
> + randv = 0;
> + }
> + if (randv)
> + srand(randv);
> + else
> +#endif
> + srand(seed_mac());
> }
>
> #endif /* __NET_RAND_H__ */
