RSA and Diffie-Hellman performance [Was: RFR(L): 8069539: RSA acceleration]

[Viswanathan, Sandhya]

Hi Tony,

Please let us know if you are ok with the changes in BigInteger.java (range checks) in patch from Intel:

http://cr.openjdk.java.net/~kvn/8069539/webrev.01/

Per Andrew's email below we could go ahead with this patch and it shouldn't affect his work.

Best Regards,
Sandhya


-----Original Message-----
From: hotspot-compiler-dev [mailto:hotspot-compiler-dev-bounces at openjdk.java.net] On Behalf Of Andrew Haley
Sent: Wednesday, May 27, 2015 10:12 AM
To: Christian Thalinger
Cc: Vladimir Kozlov; hotspot-compiler-dev at openjdk.java.net
Subject: RSA and Diffie-Hellman performance [Was: RFR(L): 8069539: RSA acceleration]

An update:

I'm still working on this.  Following last week's revelations [1] it
seems to me that a faster implementation of (integer) D-H is even more
important.

I've spent a couple of days tracking down an extremely odd feature
(bug?) in MutableBigInteger which was breaking everything, but I'm
past that now.  I'm trying to produce an intrinsic implementation of
the core modular exponentiation which is as fast as any state-of-the-
art implementation while disrupting the common code as little as
possible; this is not easy.

I hope to have something which is faster on all processors, not just
those for which we have hand-coded assembly-language implementations.

I don't think that my work should be any impediment to Sadya's patch
for squareToLen at http://cr.openjdk.java.net/~kvn/8069539/webrev.01/
being committed.  It'll still be useful.

Andrew.


[1]  Imperfect Forward Secrecy: How Diffie-Hellman Fails in Practice
https://weakdh.org/imperfect-forward-secrecy.pdf