Any one see this Cryptographic?

[winndy]

Originally Posted by cbs

Well, not the best way but applicable... only for study!

Yes,sir,It's only for study!

Originally Posted by cbs

I've received PM asking which tool by Satoshi Tomabechi to use. Generally PPSIQS is used.
But don't use RSA Tool for large composite numbers. It's too slow. I have tested RSA Tool vs PPSIQS and PPSIQS is approximately 3 (!) times faster. I tried RSA-255/256 many times and on my machine I get factors for a bit more than one hour. RSA Tool requires ~4-5 hours for the same task. RSA Tool is designed for 'playing' with numbers and keys generation And it's much better to use specialized tools for factoring.

I agree with you!I got the factors by PPSIQS in about 1 hour.
But RSAtool is very slow.
I use RSAtool to calculate D.

Originally Posted by cbs

BTW I'm not sure if RSA Tool keys generation scheme is secure

Have you look at API Spy Version 2.5,by Vitaly Evseenko?

I downloaded it from programmerstools.
I cracked it,a username could have many keys.
In fact,It uses RSA.
When I search RSA in tut from pediy.com(chinese site),
I found someone has cracked the apis32,and made a keygen.
In the tut,he said it used RSA,and surely it was!
I got a little puzzled.
In RSA,one username has one code.
But i could get two or four ,or more.
Does RSA have collision like MD5?
If so,RSA should not be used on digital signature.

Regards