All of
 help / color / mirror / Atom feed
From: "Theodore Ts'o" <>
To: Linux Kernel Developers List <>
Cc: "Theodore Ts'o" <>
Subject: [PATCH] random: use arch-specific RNG to initialize the entropy store
Date: Thu, 22 Dec 2011 16:28:01 -0500	[thread overview]
Message-ID: <> (raw)
In-Reply-To: <>

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" <>
 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 6035ab8..f10780a 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -961,6 +961,7 @@ EXPORT_SYMBOL(get_random_bytes);
 static void init_std_data(struct entropy_store *r)
+	int i;
 	ktime_t now;
 	unsigned long flags;
@@ -970,6 +971,11 @@ 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())));

           reply	other threads:[~2011-12-22 21:28 UTC|newest]

Thread overview: expand[flat|nested]  mbox.gz  Atom feed
 [parent not found: <>]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \ \ \ \
    --subject='Re: [PATCH] random: use arch-specific RNG to initialize the entropy store' \

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.