GCM counter inc

2012-06-20 Thread Ronen Shitrit
Hi

According to the GCM NIST publication, the counter increment should be
module 32 bit.
Looking into the crypto code, I can see that when using gcm(aes) the
gcm will use the ctr over aes,
ctr.c is using the crypto_inc with size of blocksize, which is 16 for AES.
in case crypto_inc will overflow in 32bit it will inc the next 32bit...

Is this a bug or am I missing something?

Regards
--
To unsubscribe from this list: send the line "unsubscribe linux-crypto" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html


Re: GCM counter inc

2012-06-29 Thread Ronen Shitrit
Can someone verify if it is a bug?

Thanks

On Wed, Jun 20, 2012 at 11:44 AM, Ronen Shitrit  wrote:
> Hi
>
> According to the GCM NIST publication, the counter increment should be
> module 32 bit.
> Looking into the crypto code, I can see that when using gcm(aes) the
> gcm will use the ctr over aes,
> ctr.c is using the crypto_inc with size of blocksize, which is 16 for AES.
> in case crypto_inc will overflow in 32bit it will inc the next 32bit...
>
> Is this a bug or am I missing something?
>
> Regards
--
To unsubscribe from this list: send the line "unsubscribe linux-crypto" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html