gmane.comp.cryptography.viff.devel

Re: softwares for viff

Marcel Keller — 2013-04-10T13:07:49

Dear Bharti,

It is recommended to install the packages using the package manager of 
your operating system. If this is not possible, the gmpy source code can 
be found here: http://code.google.com/p/gmpy/downloads/list
and the openssl source code can be found here: 
http://www.openssl.org/source/

I think that the latest versions, gmpy 1.16 and openssl 1.0.1 should be 
fine because VIFF only uses a small part of their API.

Best regards,
Marcel


On 03/04/13 17:10, bharti gupta wrote:

Downloads/repository down

2013-04-03T17:57:32

It appears that the VIFF repository is down as none of the downloads appear
to work and I cannot checkout the repository. Is there a time frame for
getting this working?

Mike

softwares for viff

bharti gupta — 2013-04-03T16:10:49

I cannot find GMPY for python 2.5 and openssl 0.9.8g for python 2.5.If someone has links or files then please mail them ASAP at bharti_mitr< at >yahoo.co.in.If anyother installations work other than those mentioned at viff.dk then too please tell.
Thanks

Millionaires example

Hongda Xiao — 2013-02-21T16:41:27

Hi,

I tried to test the millionaires.py, but when I tried it, the console 
shows that:

I am Millionaire 3 and I am worth 194 millions.
*** bad data from Player 1: unpack requires a string argument of length 5
*** aborting!
*** all protocols disconnected
Unhandled Error
Traceback (most recent call last):
Failure: twisted.internet.error.ConnectionLost: Connection to the other 
side was lost in a non-clean fashion.

I run it on localhost with different port number.

I tried several programs and find out that whenever I use comparison(>= 
or <=), the same error shows up.

Could you please inform me whether you have any ideas about this?

Thank you very much.

Best,
Hongda

State of byzantine agreement

2013-01-09T13:43:26

I'm looking through the malicious model protocol and reading over the PhD
dissertation document and one thing is not clear. The document mentions a
byzantine agreement protocol, but never describes how it is implemented.
Looking at the planned work page, it seems that the BA protocol is not
implemented. Is this true?

If so, I'd like to take a stab at implementing it. Any recommendations on
where to start?

If not true, is there any documentation for the protocol and where in the
code is it contained?

Thanks!

Mike

Re: Comparison Limits Question

Marcel Keller — 2012-12-04T10:18:30

Hi Nick,

According to the code, the modulus has to be at least 2^(l+2) + 2^(l+k), 
where l is bit length + 1 (default: 33), and k is the security parameter 
(default: 30). So the modulus has to be at least around 2^64.

Best regards,
Marcel


Am 06.11.2012 17:56, schrieb Nick La Rooy:

Comparison Limits Question

Nick La Rooy — 2012-11-06T17:56:37

I am looking to sort some large numbers securely, and have already run into overflows. 


Does anyone have any ballpark figures for how large numbers compared in the Toft07 runtime can be? 





Many thanks,

Nick

Re: negative numbers

Marcel Keller — 2012-07-16T12:47:40

Hi Abdelrahaman,

I can only think of Martin Geisler's PhD dissertation, which is referred 
to in the bibliography: http://viff.dk/doc/bibliography.html

However, I consider the documentation to be quite extensive. All 
functions considered necessary are explained, and there is a listing of 
the modules: http://viff.dk/doc/modindex.html

If you're looking for example code with explanations, have a look at 
beginner.py in the apps directory.

Best regards,
Marcel Keller


On 07/09/2012 06:08 PM, Abdelrahaman Aly wrote:

Re: negative numbers

Marcel Keller — 2012-06-29T15:34:22

Hi Abdelrahaman,

VIFF works with finite fields of prime order p. Computing in such a 
field corresponds to integer computation with computing modulo p after 
every operation. Therefore, -1 is the same as p-1. You can call signed() 
on a field element to get the representation in [-p/2,p).

Best regards,
Marcel


On 06/29/2012 04:20 PM, Abdelrahaman Aly wrote:

negative numbers

Abdelrahaman Aly — 2012-06-29T15:20:32

Hey Guys sorry bother, but I was wondering if there is a way to handle
negative values? I am doing some subtractions with shares and having some
negative values as a result but It always end up out of bounds.

Thanks in advance.

Abdelrahaman Aly
C.O.R.E- U.C.L

[issue85] Shamir secret sharing fails when a singleshare given to recombine

Satvik Chauhan — 2012-05-29T09:26:49

New submission from Satvik Chauhan <mystic.satvik< at >gmail.com>:

[([1], [100]), ([2], [100]), ([3], [100]), ([4], [100]), ([5], [100]), 
([6], [100]), ([7], [100]), ([8], [100]), ([9], [100]), ([10], [100])]
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python2.7/dist-packages/viff-1.0-
py2.7.egg/viff/shamir.py", line 121, in recombine
    vector.append(reduce(operator.mul, factors))
TypeError: reduce() of empty sequence with no initial value
[100]

----------
messages: 319
nosy: satvikc
status: unread
title: Shamir secret sharing fails when a single share given to recombine
type: bug

____________________________________
VIFF Issue Tracker <tracker< at >viff.dk>
<http://tracker.viff.dk/issue85>
____________________________________

Re: Security student

Dario Amoruso — 2011-10-17T09:17:34

good morning
the context of reference are Oppnets not collaborative

2011/10/17 Martin Burkhart <martin.burkhart< at >gmail.com>

Re: Security student

Martin Burkhart — 2011-10-17T06:35:48

Hi Dario

The SEPIA library (www.sepia.ee.ethz.ch) is also implemented in Java.
The code is available (LGPL). It supports less-than comparisons, which
is all you need for the Millionaire's problem.

Best
Martin


On 16.10.2011 22:32, Martin Geisler wrote:

Re: Security student

Martin Geisler — 2011-10-16T20:32:24

Hi Dario,

Please reply to the mailinglist, especially if you have followup
questions :-)

As I remember it, the FairPlay system is written in Java, so maybe you
can use this. Perhaps someone else on the mailinglist knows more.

Re: Security student

Martin Geisler — 2011-10-13T10:58:22


Yes, it's implemented:

  http://hg.viff.dk/viff/file/tip/apps/millionaires.py

Please post to the mailinglist (viff-devel< at >viff.dk) instead of me
personally as I'm no longer the maintainer of VIFF.

Re: Error while testing VIFF

shahriar rahman — 2011-08-19T07:55:04

Hi Marcel,

Yeah, the problem was due to cygwin. I have removed cygwin, and reinstalled
everything (python...viff). But some DLL files were missing in system32,
so I had to bring those *.dll files from openssl\bin to system32. Now
everything is working fine.
Thanks a lot for your nice support :)

--Moha

On Thu, Aug 18, 2011 at 11:26 PM, shahriar rahman <mail.jaist< at >gmail.com>wrote:

Re: Error while testing VIFF

shahriar rahman — 2011-08-18T14:26:26

I have got cygwin preinstalled in my pc. The python script is getting
different path than the sys.path. I guess it is because of the cygwin, but
not sure.
I will let you know what happens after removing cygwin.
Thanks.

Re: Error while testing VIFF

Marcel Keller — 2011-08-18T14:04:37

Well, the paths are completely different to the previous output. VIFF 
has to be installed in one of the paths to work. Did you call Python in 
the same way both times? It seems that you use cygwin here, but not earlier.

Regards,
Marcel


shahriar rahman wrote:

Re: Error while testing VIFF

shahriar rahman — 2011-08-17T08:27:41

Hello,

Thanks. I have tried that, but no error shown.

I tried to reinstall different versions as follows:

       Python: 2.5.4
       Twisted: Twisted_NoDocs-8.1.0.win32-py2.5
       OpenSSL: openssl-0.9.8g_win32
       PyOpenSSL: pyOpenSSL-0.7.win32-py2.5
       GMPY: gmpy-1.03-gmp-4.2.1.win32-py2.5
       VIFF: viff-0.7.1


Now, I am getting "No module named viff.config" as earlier. But while trying
to run millionaires.py, I am getting "ImportError: No module named
twisted.internet" instead of "viff.reactor" (that I got earlier). I have
checked the sys.path. Also, "import twisted.internet" does not show any
error.

Any suggestions?

Best regards,
Moha


On Tue, Aug 16, 2011 at 8:04 PM, Marcel Keller <mkeller< at >cs.au.dk> wrote:

Re: Error while testing VIFF

shahriar rahman — 2011-08-15T23:48:30

Hi Marcel,

Thanks. I have checked the sys.path and got the following:

['C:\\Python25\\Lib\\idlelib', 'C:\\Windows\\system32\\python25.zip',
'C:\\Python25\\DLLs', 'C:\\Python25\\lib', 'C:\\Python25\\lib\\plat-win',
'C:\\Python25\\lib\\lib-tk', 'C:\\Python25',
'C:\\Python25\\lib\\site-packages']

Now, how can I move forward?

Thanks again.

Re: Error while testing VIFF

Marcel Keller — 2011-08-16T11:04:08

Hi,

you can try the following:

 >>> import viff.config

If there is an error message, VIFF is not installed properly. If there 
isn't any, my only explanation is that Python uses different paths 
depending on whether executing a script or the command line. The latter 
would seem odd to me.

Best regards,
Marcel


shahriar rahman wrote: