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| author | Theodore Ts'o <tytso@mit.edu> | 2011-12-22 22:28:01 +0100 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2012-01-16 20:18:21 +0100 |
| commit | 3e88bdff1c65145f7ba297ccec69c774afe4c785 (patch) | |
| tree | 2d01752cdd8a5b3f1cbcad3e0ef55d6f02696efd /drivers/char | |
| parent | random: Use arch_get_random_int instead of cycle counter if avail (diff) | |
| download | linux-3e88bdff1c65145f7ba297ccec69c774afe4c785.tar.xz linux-3e88bdff1c65145f7ba297ccec69c774afe4c785.zip | |
random: Use arch-specific RNG to initialize the entropy store
If there is an architecture-specific random number generator (such as
RDRAND for Intel architectures), use it to initialize /dev/random's
entropy stores. Even in the worst case, if RDRAND is something like
AES(NSA_KEY, counter++), it won't hurt, and it will definitely help
against any other adversaries.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Link: http://lkml.kernel.org/r/1324589281-31931-1-git-send-email-tytso@mit.edu
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'drivers/char')
| -rw-r--r-- | drivers/char/random.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/char/random.c b/drivers/char/random.c index 85da8740586b..30794779c523 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -965,6 +965,7 @@ EXPORT_SYMBOL(get_random_bytes); */ static void init_std_data(struct entropy_store *r) { + int i; ktime_t now; unsigned long flags; @@ -974,6 +975,11 @@ static void init_std_data(struct entropy_store *r) now = ktime_get_real(); mix_pool_bytes(r, &now, sizeof(now)); + for (i = r->poolinfo->poolwords; i; i--) { + if (!arch_get_random_long(&flags)) + break; + mix_pool_bytes(r, &flags, sizeof(flags)); + } mix_pool_bytes(r, utsname(), sizeof(*(utsname()))); } |