| Message ID | 20201216162807.10685-3-matthias.bgg@kernel.org |
|---|---|
| State | Superseded |
| Delegated to: | Tom Rini |
| Headers | show |
| Series | Use RNG to get random behaviour | expand |
Hi Mattias, On Wed, 16 Dec 2020 at 09:28, <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> > > --- > > Changes in v2: > - fix dm_rng_read() parameters > - add missing include file > > net/net_rand.h | 19 ++++++++++++++++++- > 1 file changed, 18 insertions(+), 1 deletion(-) > > diff --git a/net/net_rand.h b/net/net_rand.h > index 4bf9bd817e..e7299973a3 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()); > +#if defined(CONFIG_DM_RNG) if (IS_ENABLED()) Similar comment to the other patch > + int ret; > + struct udevice *devp; > + u32 randv = 0; > + > + 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 > +#endif > + srand(seed_mac()); > } > > #endif /* __NET_RAND_H__ */ > -- > 2.29.2 >
diff --git a/net/net_rand.h b/net/net_rand.h index 4bf9bd817e..e7299973a3 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()); +#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(devp, &randv, sizeof(randv)); + if (ret < 0) + randv = 0; + } + if (randv) + srand(randv); + else +#endif + srand(seed_mac()); } #endif /* __NET_RAND_H__ */