Am Montag, 16. Februar 2015 20:59:33 UTC+1 schrieb Jeffrey Walton:
>
>
>
> On Sunday, February 15, 2015 at 8:03:06 PM UTC-5, Jeffrey Walton wrote:
>>
>>
>> On Sunday, February 15, 2015 at 7:13:42 AM UTC-5, Aydin Abadi wrote:
>>>
>>> I need to know how I can store (or access) the seed generated by a 
>>> pseudorandom generator in crypto++. So i need to access the random seed to 
>>> re-use it for some purpose.
>>>
>>
>> You will probably have to use a RandomPool and manage the seed yourself. 
>> See the wiki page on RandomNumberGenerator for details (
>> http://www.cryptopp.com/wiki/RandomNumberGenerator). 
>>
>
> A RandomPool is the wrong tool here because it also uses time in its 
> calculations. Sorry about that - I should have checked before I made the 
> recommendation.
>
> You can use OFB_Mode<T>::Encryption because it indirectly inherits from 
> RandomNumberGenerator by way of AdditiveCipherTemplate<T>. For T (the T for 
> OFB mode), use something like 3-key TripleDES, Camellia or AES. Crypto++'s 
> test.cpp actually uses the AES/OFB generator (its the thing returned from 
> GlobalPRNG()). Note: other modes of operation do *not* inherit from 
> RandomNumberGenerator, so you can't use them in this instance.
>

 Except for CTR-Mode.
Any cipher running in CTR mode can be used as PRNG.

BR

JPM

>
> There's also an alternate AES-256 based generator available on the wiki 
> page at http://www.cryptopp.com/wiki/RandomNumberGenerator. Fetch the 
> AES_RNG header file if you are interested in using it (its a header only 
> implementation).
>
> Jeff
>
>

-- 
-- 
You received this message because you are subscribed to the "Crypto++ Users" 
Google Group.
To unsubscribe, send an email to [email protected].
More information about Crypto++ and this group is available at 
http://www.cryptopp.com.
--- 
You received this message because you are subscribed to the Google Groups 
"Crypto++ Users" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
For more options, visit https://groups.google.com/d/optout.

Reply via email to