[PATCH 35/38] crypto: drbg - Change DRBG_MAX_REQUESTS to 4096

[Eric Biggers]

Currently a formal reseed happens only after each 1048576 requests.

That's quite a high number.  Let's follow the example of BoringSSL and
use a more conservative value of 4096.

Note that in practice this makes little difference, now that we're
including 32 bytes from get_random_bytes() in the additional input on
every request anyway, which is a de facto reseed.

But for the same reason, we might as well decrease the actual reseed
interval to something more reasonable.

Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
---
 crypto/drbg.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/crypto/drbg.c b/crypto/drbg.c
index cda79d601f4f..7fd076ddc105 100644
--- a/crypto/drbg.c
+++ b/crypto/drbg.c
@@ -113,11 +113,11 @@ enum drbg_seed_state {
 
 /*
  * Maximum number of requests before reseeding is forced.
  * SP800-90A allows this to be up to 2**48.  We use a lower value.
  */
-#define DRBG_MAX_REQUESTS	(1 << 20)
+#define DRBG_MAX_REQUESTS	4096
 
 /*
  * Maximum number of random bytes that can be requested at once.
  * SP800-90A allows up to 2**19 bits, which is 2**16 bytes.
  */
-- 
2.53.0