Re: [tor-dev] Iran
On Sun, May 05, 2013 at 10:44:01PM +0300, Kostas Jakeliunas wrote: > Also, 'Format-Transforming Encryption' looks > interesting, but I take it not much in terms of implementation beyond a > research paper [2] (which looks interesting). > > [2]https://eprint.iacr.org/2012/494 I haven't tried it yet, but they do have an implementation and are inviting testers. http://fte.kpdyer.com/ David Fifield ___ tor-dev mailing list tor-dev@lists.torproject.org https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev
Re: [tor-dev] Iran
(Sorry, last email for now --) I see that "StegoTorus is an Obfsproxy fork that extends it to a) split Tor streams across multiple connections to avoid packet size signatures, and b) embed the traffic flows in traces that look like html, javascript, or pdf." However, its public repo seems to haven't been updated for more than nine months. [1] Also, 'Format-Transforming Encryption' looks interesting, but I take it not much in terms of implementation beyond a research paper [2] (which looks interesting). [1] https://gitweb.torproject.org/stegotorus.git [2] https://eprint.iacr.org/2012/494 On Sun, May 5, 2013 at 10:08 PM, Kostas Jakeliunas wrote: > > have there been any attempts to produce a pluggable transport which > would emulate http? > > (Ah, I suppose there've been quite a bit of discussion indeed. ( > https://trac.torproject.org/projects/tor/ticket/8676, etc.)) > > > On Sun, May 5, 2013 at 9:58 PM, Kostas Jakeliunas > wrote: > >> > If we had a PT that encapsulated obfs3 inside >> the body of http then this may work. >> >> I'm probably missing some previous discussions which might have covered >> it, but: have there been any attempts to produce a pluggable transport >> which would emulate http? Basically, have the transport use http headers, >> and put all encrypted data in the body (possibly prepending it with some >> html tags even)? This sounds like a nice idea. >> >> >> On Sun, May 5, 2013 at 9:41 PM, Matthew Finkel >> wrote: >> >>> On Sun, May 05, 2013 at 04:18:56PM +0300, George Kadianakis wrote: >>> > tor-admin writes: >>> > >>> > > On Sunday 05 May 2013 14:50:51 George Kadianakis wrote: >>> > >> It would be interesting to learn which ports they currently >>> whitelist, >>> > >> except from the usual HTTP/HTTPS. >>> > >> >>> > >> I also wonder if they just block based on TCP port, or whether they >>> > >> also have DPI heuristics. >>> > >> >>> > >> On the Tor side, it seems like we should start looking into #7875: >>> > >> https://trac.torproject.org/projects/tor/ticket/7875 >>> > >> ___ >>> > > I am wondering if here is there a way for a user to ask bridgedb for >>> a bridge >>> > > with a specific port? >>> > > ___ >>> > > tor-dev mailing list >>> > > tor-dev@lists.torproject.org >>> > > https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev >>> > >>> > If I remember correctly BridgeDB tries (in a best-effort manner) to >>> > give users bridges that are listening on port 443. Obfuscated bridges >>> > that bind on 443 are not very common (because of #7875) so I guess >>> > that not many obfuscated bridges on 443 are given out. >>> > >>> > In any case, I don't think that a user can explicitly ask BridgeDB for >>> > a bridge on a specific port, but this might be a useful feature >>> > request (especially if this "filtering based on TCP port" tactic >>> > continues). >>> >>> This may be a good feature to have, in general, but it does not sound >>> like >>> this will solve the current problem in Iran. The last report says >>> they're whitelisting ports *and* protocols[1]. So even if a user attempts >>> to use obfs3 on port 443 it'll likely be blocked because obfs3 is not a >>> look-like-https protocol. If we had a PT that encapsulated obfs3 inside >>> the body of http then this may work. CDA also says SSL/TLS connections >>> are throttled to 5% of the normal speed [2], so that's no fun either. >>> >>> [1] https://twitter.com/CDA/status/331006059923795968 >>> [2] https://twitter.com/CDA/status/331040305648369664 >>> ___ >>> tor-dev mailing list >>> tor-dev@lists.torproject.org >>> https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev >>> >> >> > ___ tor-dev mailing list tor-dev@lists.torproject.org https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev
Re: [tor-dev] Iran
> If we had a PT that encapsulated obfs3 inside the body of http then this may work. I'm probably missing some previous discussions which might have covered it, but: have there been any attempts to produce a pluggable transport which would emulate http? Basically, have the transport use http headers, and put all encrypted data in the body (possibly prepending it with some html tags even)? This sounds like a nice idea. On Sun, May 5, 2013 at 9:41 PM, Matthew Finkel wrote: > On Sun, May 05, 2013 at 04:18:56PM +0300, George Kadianakis wrote: > > tor-admin writes: > > > > > On Sunday 05 May 2013 14:50:51 George Kadianakis wrote: > > >> It would be interesting to learn which ports they currently whitelist, > > >> except from the usual HTTP/HTTPS. > > >> > > >> I also wonder if they just block based on TCP port, or whether they > > >> also have DPI heuristics. > > >> > > >> On the Tor side, it seems like we should start looking into #7875: > > >> https://trac.torproject.org/projects/tor/ticket/7875 > > >> ___ > > > I am wondering if here is there a way for a user to ask bridgedb for a > bridge > > > with a specific port? > > > ___ > > > tor-dev mailing list > > > tor-dev@lists.torproject.org > > > https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev > > > > If I remember correctly BridgeDB tries (in a best-effort manner) to > > give users bridges that are listening on port 443. Obfuscated bridges > > that bind on 443 are not very common (because of #7875) so I guess > > that not many obfuscated bridges on 443 are given out. > > > > In any case, I don't think that a user can explicitly ask BridgeDB for > > a bridge on a specific port, but this might be a useful feature > > request (especially if this "filtering based on TCP port" tactic > > continues). > > This may be a good feature to have, in general, but it does not sound like > this will solve the current problem in Iran. The last report says > they're whitelisting ports *and* protocols[1]. So even if a user attempts > to use obfs3 on port 443 it'll likely be blocked because obfs3 is not a > look-like-https protocol. If we had a PT that encapsulated obfs3 inside > the body of http then this may work. CDA also says SSL/TLS connections > are throttled to 5% of the normal speed [2], so that's no fun either. > > [1] https://twitter.com/CDA/status/331006059923795968 > [2] https://twitter.com/CDA/status/331040305648369664 > ___ > tor-dev mailing list > tor-dev@lists.torproject.org > https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev > ___ tor-dev mailing list tor-dev@lists.torproject.org https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev
Re: [tor-dev] Iran
> have there been any attempts to produce a pluggable transport which would emulate http? (Ah, I suppose there've been quite a bit of discussion indeed. ( https://trac.torproject.org/projects/tor/ticket/8676, etc.)) On Sun, May 5, 2013 at 9:58 PM, Kostas Jakeliunas wrote: > > If we had a PT that encapsulated obfs3 inside > the body of http then this may work. > > I'm probably missing some previous discussions which might have covered > it, but: have there been any attempts to produce a pluggable transport > which would emulate http? Basically, have the transport use http headers, > and put all encrypted data in the body (possibly prepending it with some > html tags even)? This sounds like a nice idea. > > > On Sun, May 5, 2013 at 9:41 PM, Matthew Finkel > wrote: > >> On Sun, May 05, 2013 at 04:18:56PM +0300, George Kadianakis wrote: >> > tor-admin writes: >> > >> > > On Sunday 05 May 2013 14:50:51 George Kadianakis wrote: >> > >> It would be interesting to learn which ports they currently >> whitelist, >> > >> except from the usual HTTP/HTTPS. >> > >> >> > >> I also wonder if they just block based on TCP port, or whether they >> > >> also have DPI heuristics. >> > >> >> > >> On the Tor side, it seems like we should start looking into #7875: >> > >> https://trac.torproject.org/projects/tor/ticket/7875 >> > >> ___ >> > > I am wondering if here is there a way for a user to ask bridgedb for >> a bridge >> > > with a specific port? >> > > ___ >> > > tor-dev mailing list >> > > tor-dev@lists.torproject.org >> > > https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev >> > >> > If I remember correctly BridgeDB tries (in a best-effort manner) to >> > give users bridges that are listening on port 443. Obfuscated bridges >> > that bind on 443 are not very common (because of #7875) so I guess >> > that not many obfuscated bridges on 443 are given out. >> > >> > In any case, I don't think that a user can explicitly ask BridgeDB for >> > a bridge on a specific port, but this might be a useful feature >> > request (especially if this "filtering based on TCP port" tactic >> > continues). >> >> This may be a good feature to have, in general, but it does not sound like >> this will solve the current problem in Iran. The last report says >> they're whitelisting ports *and* protocols[1]. So even if a user attempts >> to use obfs3 on port 443 it'll likely be blocked because obfs3 is not a >> look-like-https protocol. If we had a PT that encapsulated obfs3 inside >> the body of http then this may work. CDA also says SSL/TLS connections >> are throttled to 5% of the normal speed [2], so that's no fun either. >> >> [1] https://twitter.com/CDA/status/331006059923795968 >> [2] https://twitter.com/CDA/status/331040305648369664 >> ___ >> tor-dev mailing list >> tor-dev@lists.torproject.org >> https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev >> > > ___ tor-dev mailing list tor-dev@lists.torproject.org https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev
Re: [tor-dev] Iran
On Sun, May 05, 2013 at 04:18:56PM +0300, George Kadianakis wrote: > tor-admin writes: > > > On Sunday 05 May 2013 14:50:51 George Kadianakis wrote: > >> It would be interesting to learn which ports they currently whitelist, > >> except from the usual HTTP/HTTPS. > >> > >> I also wonder if they just block based on TCP port, or whether they > >> also have DPI heuristics. > >> > >> On the Tor side, it seems like we should start looking into #7875: > >> https://trac.torproject.org/projects/tor/ticket/7875 > >> ___ > > I am wondering if here is there a way for a user to ask bridgedb for a > > bridge > > with a specific port? > > ___ > > tor-dev mailing list > > tor-dev@lists.torproject.org > > https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev > > If I remember correctly BridgeDB tries (in a best-effort manner) to > give users bridges that are listening on port 443. Obfuscated bridges > that bind on 443 are not very common (because of #7875) so I guess > that not many obfuscated bridges on 443 are given out. > > In any case, I don't think that a user can explicitly ask BridgeDB for > a bridge on a specific port, but this might be a useful feature > request (especially if this "filtering based on TCP port" tactic > continues). This may be a good feature to have, in general, but it does not sound like this will solve the current problem in Iran. The last report says they're whitelisting ports *and* protocols[1]. So even if a user attempts to use obfs3 on port 443 it'll likely be blocked because obfs3 is not a look-like-https protocol. If we had a PT that encapsulated obfs3 inside the body of http then this may work. CDA also says SSL/TLS connections are throttled to 5% of the normal speed [2], so that's no fun either. [1] https://twitter.com/CDA/status/331006059923795968 [2] https://twitter.com/CDA/status/331040305648369664 ___ tor-dev mailing list tor-dev@lists.torproject.org https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev
Re: [tor-dev] Iran
tor-admin writes: > On Sunday 05 May 2013 14:50:51 George Kadianakis wrote: >> It would be interesting to learn which ports they currently whitelist, >> except from the usual HTTP/HTTPS. >> >> I also wonder if they just block based on TCP port, or whether they >> also have DPI heuristics. >> >> On the Tor side, it seems like we should start looking into #7875: >> https://trac.torproject.org/projects/tor/ticket/7875 >> ___ > I am wondering if here is there a way for a user to ask bridgedb for a bridge > with a specific port? > ___ > tor-dev mailing list > tor-dev@lists.torproject.org > https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev If I remember correctly BridgeDB tries (in a best-effort manner) to give users bridges that are listening on port 443. Obfuscated bridges that bind on 443 are not very common (because of #7875) so I guess that not many obfuscated bridges on 443 are given out. In any case, I don't think that a user can explicitly ask BridgeDB for a bridge on a specific port, but this might be a useful feature request (especially if this "filtering based on TCP port" tactic continues). ___ tor-dev mailing list tor-dev@lists.torproject.org https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev
Re: [tor-dev] Iran
On Sunday 05 May 2013 14:50:51 George Kadianakis wrote: > It would be interesting to learn which ports they currently whitelist, > except from the usual HTTP/HTTPS. > > I also wonder if they just block based on TCP port, or whether they > also have DPI heuristics. > > On the Tor side, it seems like we should start looking into #7875: > https://trac.torproject.org/projects/tor/ticket/7875 > ___ I am wondering if here is there a way for a user to ask bridgedb for a bridge with a specific port? ___ tor-dev mailing list tor-dev@lists.torproject.org https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev
Re: [tor-dev] Iran
Nima writes: > George Kadianakis: >> Nima writes: >> >>> Iran is actively dropping connections to *any* unknown port right after >>> *60secs*. >>> Pluggable Transport successfully connects to Tor network, Although it >>> can not make a circuit in many ISPs including "Mobin". >> >> Ugh. This sucks. >> >> What do you mean by "unknown port"? Which ports do they allow? > > Not sure yet. Mostly like they've whitelisted the known protocols. > I didn't have a chance to login to my box yet :/ > I see. It would be interesting to learn which ports they currently whitelist, except from the usual HTTP/HTTPS. I also wonder if they just block based on TCP port, or whether they also have DPI heuristics. On the Tor side, it seems like we should start looking into #7875: https://trac.torproject.org/projects/tor/ticket/7875 ___ tor-dev mailing list tor-dev@lists.torproject.org https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev
Re: [tor-dev] Iran
George Kadianakis: > Nima writes: > >> Iran is actively dropping connections to *any* unknown port right after >> *60secs*. >> Pluggable Transport successfully connects to Tor network, Although it >> can not make a circuit in many ISPs including "Mobin". > > Ugh. This sucks. > > What do you mean by "unknown port"? Which ports do they allow? Not sure yet. Mostly like they've whitelisted the known protocols. I didn't have a chance to login to my box yet :/ https://twitter.com/search?q=%23filternet&src=hash -- Nima 0x1C92A77B "I disapprove of what you say, but I will defend to the death your right to say it" --Evelyn Beatrice Hall signature.asc Description: OpenPGP digital signature ___ tor-dev mailing list tor-dev@lists.torproject.org https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev
Re: [tor-dev] Iran
Nima writes: > Iran is actively dropping connections to *any* unknown port right after > *60secs*. > Pluggable Transport successfully connects to Tor network, Although it > can not make a circuit in many ISPs including "Mobin". Ugh. This sucks. What do you mean by "unknown port"? Which ports do they allow? ___ tor-dev mailing list tor-dev@lists.torproject.org https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev
[tor-dev] Iran
Iran is actively dropping connections to *any* unknown port right after *60secs*. Pluggable Transport successfully connects to Tor network, Although it can not make a circuit in many ISPs including "Mobin". -- Nima 0x1C92A77B "I disapprove of what you say, but I will defend to the death your right to say it" --Evelyn Beatrice Hall signature.asc Description: OpenPGP digital signature ___ tor-dev mailing list tor-dev@lists.torproject.org https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev
