diff options
| author | Stephan Mueller <smueller@chronox.de> | 2024-08-12 08:25:42 +0200 |
|---|---|---|
| committer | Herbert Xu <herbert@gondor.apana.org.au> | 2024-08-24 21:36:07 +0800 |
| commit | 95a798d20060d2b648dd604321e347c85edfd783 (patch) | |
| tree | c4ff9cf10e2fdea3cc3c3627b3efe94b569dab31 /crypto | |
| parent | 8e84a650079a0044374f57af8d24b367fc795340 (diff) | |
crypto: jitter - set default OSR to 3
The user space Jitter RNG library uses the oversampling rate of 3 which
implies that each time stamp is credited with 1/3 bit of entropy. To
obtain 256 bits of entropy, 768 time stamps need to be sampled. The
increase in OSR is applied based on a report where the Jitter RNG is
used on a system exhibiting a challenging environment to collect
entropy.
This OSR default value is now applied to the Linux kernel version of
the Jitter RNG as well.
The increase in the OSR from 1 to 3 also implies that the Jitter RNG is
now slower by default.
Reported-by: Jeff Barnes <jeffbarnes@microsoft.com>
Signed-off-by: Stephan Mueller <smueller@chronox.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'crypto')
| -rw-r--r-- | crypto/Kconfig | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/crypto/Kconfig b/crypto/Kconfig index 72e2decb8c6a..a779cab668c2 100644 --- a/crypto/Kconfig +++ b/crypto/Kconfig @@ -1305,7 +1305,7 @@ config CRYPTO_JITTERENTROPY_MEMORY_BLOCKSIZE config CRYPTO_JITTERENTROPY_OSR int "CPU Jitter RNG Oversampling Rate" range 1 15 - default 1 + default 3 help The Jitter RNG allows the specification of an oversampling rate (OSR). The Jitter RNG operation requires a fixed amount of timing |