- Timing Attacks on Implementations of Diffie Hellman, RSA, DSS, and
Other Systems.
- Excellent Paper written by Paul C. Kocher from Stanford. He
currently is a cryptography consultant.
- This full paper can be seen at http://www.cryptography.com
- Quick Abstract: By carefully measuring the amount of time required
to perform private key operations, attackers may be able to find fixed
Diffie-Hellman exponents, factor RSA keys, and break other cryptosytems.
- RSA quickly issued a press release to defend it's algorithm.
- They suggested two methods of defense:
- First is to artificially "equalize" decryption times.
- Second is to use "blinding", in which a random number is
introduced into the decryption process, making it impossible to
get any useful data out of timing these transactions.
- Paul also wrote a paper on breaking PKZIP password encrypted files.
- Abstract: You can find the password if you have a few hundred
bytes of known plaintext.
- Someone has converted this into a C Program available on the web.
Copyright 1997 by Slackers Union. Comments should go to any of the
group members. Opinions reflected on this page are by no means
opinions
of UCSD. Go sue somebody else.
Last Modified: June 1st, 1997
|