Re: (newbie) rsa ciphertext and plaintext

From: Tom St Denis (tomstdenis_at_iahu.ca)
Date: 01/16/04 

Date: Fri, 16 Jan 2004 16:07:20 GMT

"vedaal" <vedaal@hotmail.com> wrote in message
news:bu925j$f3ugr$1@ID-99877.news.uni-berlin.de...
>
> "Tom St Denis" <tomstdenis@iahu.ca> wrote in message
> news:KyHNb.169234$AAe1.101529@news01.bloor.is.net.cable.rogers.com...
>
> [...]
>
> > > can the non-randomness of this second 'session key' with its padding,
> > > be distinguished from the first typical session key with padding,
> > > after both are encrypted to the same rsa key?
> >
> > I don't get it. How do you hide the second key in the first?
>
> you don't
>
> the issue is that if the 'second' session key is encrypted to an rsa key,
> and the entire packet substituted for the
> packet with the real session key,
>
> then,
> can an interceptor determine by examining the ciphertext of the rsa
> encrypted session key,
> that the session key used is 'not' random?

The answer is no then. In fact a proper implementation of RSA would allow
you to encrypt *the same* message over and over and produce seemingly random
ciphertexts.

Tom

Relevant Pages

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