Re: [tor-dev] Draft Proposal: Random Number Generation During Tor Voting

2015-09-16 Thread David Goulet
> George Kadianakis writes: > >> Hello there, >> > > Hello, > > I'm inlining the latest version of proposal250. > > It includes various improvements, like completely removing the need for an SR > doc (which will make implementation much much easier), and switching to > signature-based commitme

Re: [tor-dev] Draft Proposal: Random Number Generation During Tor Voting

2015-09-15 Thread George Kadianakis
George Kadianakis writes: > Hello there, > Hello, I'm inlining the latest version of proposal250. It includes various improvements, like completely removing the need for an SR doc (which will make implementation much much easier), and switching to signature-based commitments which are attribut

Re: [tor-dev] Draft Proposal: Random Number Generation During Tor Voting

2015-09-08 Thread Nick Mathewson
On Tue, Sep 8, 2015 at 7:10 AM, David Goulet wrote: > On 08 Sep (01:04:36), Tim Wilson-Brown - teor wrote: >> >> > On 7 Sep 2015, at 23:36, David Goulet wrote: >> > ... >> > Please review it, mostly format of the state (before the SR document) >> > has changed. As well as a new "conflict" line is

Re: [tor-dev] Draft Proposal: Random Number Generation During Tor Voting

2015-09-08 Thread David Goulet
On 08 Sep (01:04:36), Tim Wilson-Brown - teor wrote: > > > On 7 Sep 2015, at 23:36, David Goulet wrote: > > ... > > Please review it, mostly format of the state (before the SR document) > > has changed. As well as a new "conflict" line is added to the vote. > > … > > > > If an authority sees tw

Re: [tor-dev] Draft Proposal: Random Number Generation During Tor Voting

2015-09-08 Thread s7r
-BEGIN PGP SIGNED MESSAGE- Hash: SHA256 I disagree. can you describe how exactly? What exactly can be gamed, if we use the protection described by me? It will provide the same security as directory authorities already have for voting about relays. It's true that ultimately anything can be

Re: [tor-dev] Draft Proposal: Random Number Generation During Tor Voting

2015-09-07 Thread Tim Wilson-Brown - teor
> On 7 Sep 2015, at 23:36, David Goulet wrote: > ... > Please review it, mostly format of the state (before the SR document) > has changed. As well as a new "conflict" line is added to the vote. > … > If an authority sees two distinct commitments from an other authority in > the same period, th

Re: [tor-dev] Draft Proposal: Random Number Generation During Tor Voting

2015-09-07 Thread David Goulet
Hello! While working on the implementation of this proposal, we realized that it was much more complicated to add a new consensus flavor than we originally anticipated. nickm then suggested to NOT use this new flavor (shared random document) and instead change it to a persistent state on disk tha

Re: [tor-dev] Draft Proposal: Random Number Generation During Tor Voting

2015-09-07 Thread Tom van der Woerdt
I'm not a big fan of automated systems that ban authorities as it may get false positives and it may be gamed and/or attacked. An alternative solution is to make the voting a two-step system: first you publish the sha256 hash of your vote, then a few minutes later you publish the actual vote.

Re: [tor-dev] Draft Proposal: Random Number Generation During Tor Voting

2015-09-07 Thread s7r
-BEGIN PGP SIGNED MESSAGE- Hash: SHA256 Hi, Sending the comments from #tor-dev here as well. This is related to the attack where exactly half of the directory authorities commit to some values, and the last directory authority can send different values to both camps, and have the ultimat

Re: [tor-dev] Draft Proposal: Random Number Generation During Tor Voting

2015-08-11 Thread teor
> On 12 Aug 2015, at 04:35 , George Kadianakis wrote: > > teor writes: > >> Another implementation note on directory caching of the SR doc: >> >> I just noticed the following code in >> update_consensus_networkstatus_downloads(): >> >> for (i=0; i < N_CONSENSUS_FLAVORS; ++i) { >>/*

Re: [tor-dev] Draft Proposal: Random Number Generation During Tor Voting

2015-08-11 Thread George Kadianakis
teor writes: > Another implementation note on directory caching of the SR doc: > > I just noticed the following code in > update_consensus_networkstatus_downloads(): > > for (i=0; i < N_CONSENSUS_FLAVORS; ++i) { > /* need some way to download unknown flavors if we are caching. */ > > Th

Re: [tor-dev] Draft Proposal: Random Number Generation During Tor Voting

2015-08-11 Thread teor
> On 10 Aug 2015, at 23:07 , George Kadianakis wrote: > > teor writes: > >>> On 4 Aug 2015, at 22:00 , George Kadianakis wrote: >>> >>> Hello, >>> >>> >>> > 3.7. Shared Randomness Disaster Recovery [SRDISASTER] > > If the consensus at 12:00UTC fails to be created, then there

Re: [tor-dev] Draft Proposal: Random Number Generation During Tor Voting

2015-08-11 Thread teor
Another implementation note on directory caching of the SR doc: I just noticed the following code in update_consensus_networkstatus_downloads(): for (i=0; i < N_CONSENSUS_FLAVORS; ++i) { /* need some way to download unknown flavors if we are caching. */ This means that any new consensus

Re: [tor-dev] Draft Proposal: Random Number Generation During Tor Voting

2015-08-10 Thread George Kadianakis
teor writes: >> On 4 Aug 2015, at 22:00 , George Kadianakis wrote: >> >> Hello, >> >> >> 3.7. Shared Randomness Disaster Recovery [SRDISASTER] If the consensus at 12:00UTC fails to be created, then there will be no new shared random value for the day. Directory

Re: [tor-dev] Draft Proposal: Random Number Generation During Tor Voting

2015-08-04 Thread teor
> On 4 Aug 2015, at 22:00 , George Kadianakis wrote: > >>> XXX The number of active participants is dynamic as authorities leave and >>> join the protocol. Since the number of active participants is dynamic , >>> an attacker could trick some authorities believing there are N >>> part

Re: [tor-dev] Draft Proposal: Random Number Generation During Tor Voting

2015-08-04 Thread teor
> On 4 Aug 2015, at 22:00 , George Kadianakis wrote: > > Hello, > > and thanks for the comments. > > I uploaded a new version of the proposal that addresses some of your feedback. > > You can find it here: > https://gitweb.torproject.org/user/asn/torspec.git/log/?h=rng-draft-v4-asn Thanks f

Re: [tor-dev] Draft Proposal: Random Number Generation During Tor Voting

2015-08-04 Thread George Kadianakis
teor writes: >> On 4 Aug 2015, at 00:03 , George Kadianakis wrote: >> … > >> 3.1.2. Shared Random Document During Commitment Phase [SRDOCCOMMIT] > … Hello, and thanks for the comments. I uploaded a new version of the proposal that addresses some of your feedback. You can find it here: http

Re: [tor-dev] Draft Proposal: Random Number Generation During Tor Voting

2015-08-03 Thread teor
> On 4 Aug 2015, at 00:03 , George Kadianakis wrote: > … > 3.1.2. Shared Random Document During Commitment Phase [SRDOCCOMMIT] … > Also, an authority should not be able to register a commitment value for a > different authority. Hence, an authority X should only vote and place in > the SR doc

Re: [tor-dev] Draft Proposal: Random Number Generation During Tor Voting

2015-08-03 Thread Paul Syverson
On Tue, Aug 04, 2015 at 12:39:50AM +1000, teor wrote: > > > On 4 Aug 2015, at 00:32 , Ian Goldberg wrote: > > > > Nice work! A couple of minor comments: > > > > On Mon, Aug 03, 2015 at 05:03:38PM +0300, George Kadianakis wrote: > >> A shared random document requires 50% + 1 authority signatu

Re: [tor-dev] Draft Proposal: Random Number Generation During Tor Voting

2015-08-03 Thread teor
> On 4 Aug 2015, at 00:32 , Ian Goldberg wrote: > > Nice work! A couple of minor comments: > > On Mon, Aug 03, 2015 at 05:03:38PM +0300, George Kadianakis wrote: >> A shared random document requires 50% + 1 authority signatures to be >> considered valid. As this proposal is being written,

Re: [tor-dev] Draft Proposal: Random Number Generation During Tor Voting

2015-08-03 Thread Ian Goldberg
Nice work! A couple of minor comments: On Mon, Aug 03, 2015 at 05:03:38PM +0300, George Kadianakis wrote: >A shared random document requires 50% + 1 authority signatures to be >considered valid. As this proposal is being written, there are 9 >authorities thus we would need 5. Careful

[tor-dev] Draft Proposal: Random Number Generation During Tor Voting

2015-08-03 Thread George Kadianakis
Hello there, we are glad to release a first draft of our proposal on distributed random generation using the Tor voting process. It specifies how Tor dirauths can generate a fresh random value every day using a commit-and-reveal protocol. The protocol piggybacks on top of the regular Tor voting pr