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Re: How is NSA breaking so much crypto?

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On 2015-10-15 01:44:53 +0000, Rich said:

> https://freedom-to-tinker.com/blog/haldermanheninger/how-is-nsa-breaking-so-much-crypto/ 
> 

The guts of this, if my skim of the presented paper is correct, is
that it is possible to perform a lot of precomputation on a DH group
in absence of data from any particular A and B from a particular use.

With this precomputation, attacks on a particular session become
easier.

Leaving aside the downgrade attacks (tricking TLS/SSL sessions to use
weaker ciphers/parameters than they would normally negotiate), I've
got a couple of questions.

1. Does this apply to elliptic curves as as well?

That is, is there precomputation that can be done on an EC group that
will make breaking any particular use of that group easier?

2. Are there good tools for generating safe primes that are available
   to developers?

That is, there is an advantage to using unpopular groups. But most
software developers will pick a group and parameters out of some
standards document. If software developers using DH want to create
new groups, how can we help them to not make bad choices of primes.

2a. Analogue of question 2 but for ECC parameters?

I am assuming that we don't need unique or unpopular curves. As long
as we stick to good curves, the analogue of (2) is to pick the right
modulus. Is this correct? And are developers going to shoot
themselves in the foot by doing so.


Cheers,

-j

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How is NSA breaking so much crypto? Rich <rich@example.invalid> - 2015-10-15 01:44 +0000
  Re: How is NSA breaking so much crypto? "Chris M. Thomasson" <nospam@nospam.nospam> - 2015-10-15 12:04 -0700
    Re: How is NSA breaking so much crypto? wizzofozz <oscxxxxxxxaas@gmail.com> - 2015-10-15 22:24 +0200
      Re: How is NSA breaking so much crypto? William Unruh <unruh@invalid.ca> - 2015-10-15 23:13 +0000
        Re: How is NSA breaking so much crypto? <william@wilbur.25thandClement.com> - 2015-10-16 18:47 -0700
      Re: How is NSA breaking so much crypto? Jan Panteltje <pNaOnStPeAlMtje@yahoo.com> - 2015-10-16 10:09 +0000
    Re: How is NSA breaking so much crypto? Rich <rich@example.invalid> - 2015-10-15 22:38 +0000
    Re: How is NSA breaking so much crypto? William Unruh <unruh@invalid.ca> - 2015-10-15 23:11 +0000
      Re: How is NSA breaking so much crypto? Jakob Bohm <jb-usenet@wisemo.com> - 2015-10-16 02:08 +0200
        Re: How is NSA breaking so much crypto? Rich <rich@example.invalid> - 2015-10-16 00:25 +0000
          Re: How is NSA breaking so much crypto? Jakob Bohm <jb-usenet@wisemo.com> - 2015-10-16 04:04 +0200
  Re: How is NSA breaking so much crypto? Jeffrey Goldberg <nobody@goldmark.org> - 2015-10-16 11:53 -0500
    Re: How is NSA breaking so much crypto? Rich <rich@example.invalid> - 2015-10-16 17:54 +0000
      Re: How is NSA breaking so much crypto? <william@wilbur.25thandClement.com> - 2015-10-16 19:14 -0700
    Re: How is NSA breaking so much crypto? Jakob Bohm <jb-usenet@wisemo.com> - 2015-10-16 20:18 +0200
    Re: How is NSA breaking so much crypto? kg <kristiag+news@math.ntnu.no> - 2015-10-16 20:59 +0000
      Re: How is NSA breaking so much crypto? Jeffrey Goldberg <nobody@goldmark.org> - 2015-10-16 23:19 -0500
        Re: How is NSA breaking so much crypto? kg <kristiag+news@math.ntnu.no> - 2015-10-18 11:37 +0000
          Re: How is NSA breaking so much crypto? Jeffrey Goldberg <nobody@goldmark.org> - 2015-10-19 00:20 -0500
  Re: How is NSA breaking so much crypto? Anonymous <nobody@remailer.paranoici.org> - 2015-10-18 22:53 +0000
    Re: How is NSA breaking so much crypto? Rich <rich@example.invalid> - 2015-10-19 01:18 +0000
  Re: How is NSA breaking so much crypto? Noob <root@127.0.0.1> - 2015-10-30 08:45 +0100

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