Message ID | 20201218092804.19753-3-matthias.bgg@kernel.org |
---|---|
State | Accepted |
Commit | ea707dc0aaafad34bba436b206af340c410dfb1b |
Delegated to: | Tom Rini |
Headers | show |
Series | Use RNG to get random behaviour | expand |
On Fri, 18 Dec 2020 10:28:04 +0100 matthias.bgg@kernel.org wrote: > From: Matthias Brugger <mbrugger@suse.com> > > 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 <mbrugger@suse.com> Reviewed-by: Torsten Duwe <duwe@suse.de>
On Fri, Dec 18, 2020 at 10:28:04AM +0100, matthias.bgg@kernel.org wrote: > From: Matthias Brugger <mbrugger@suse.com> > > 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 <mbrugger@suse.com> > Reviewed-by: Torsten Duwe <duwe@suse.de> Applied to u-boot/master, thanks!
diff --git a/net/net_rand.h b/net/net_rand.h index 4bf9bd817e..6a52cda85e 100644 --- a/net/net_rand.h +++ b/net/net_rand.h @@ -10,6 +10,8 @@ #define __NET_RAND_H__ #include <common.h> +#include <dm/uclass.h> +#include <rng.h> /* * Return a seed for the PRNG derived from the eth0 MAC address. @@ -37,7 +39,22 @@ static inline unsigned int seed_mac(void) */ static inline void srand_mac(void) { - srand(seed_mac()); + int 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(seed_mac()); } #endif /* __NET_RAND_H__ */