RSA Key Gen: Fast in Test App, Slow in Real App.

Werner Koch wk at gnupg.org
Thu Oct 5 11:11:51 CEST 2006


On Thu,  5 Oct 2006 04:52, jitspoe said:

> All I'm doing is generating a 128bit RSA key pair.  I can post the source
> code if you're interested.  Once the first RSA key has been generated,
> generating another is almost instant, so I'm guessing it's initializing some
> kind of prime table.  I haven't delved into the gcrypt code to find out.

That is because the entropy pool of the RNG has been filled and the
second key utilizes the left over entropy.  Make sure to properly
setup the RNG.

BTW, a 128 bit RSA key is pretty useless except for learning how to
break it.


Salam-Shalom,

   Werner




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