Opened 7 years ago

Closed 6 years ago

#5699 closed project (fixed)

Make Tor able to handle VoIP applications people already want to use

Reported by: karsten Owned by: mttp
Priority: Medium Milestone:
Component: Metrics/Analysis Version:
Severity: Keywords: SponsorZ, SponsorF
Cc: tails@…, adrelanos@…, mo, admin@… Actual Points:
Parent ID: Points:
Reviewer: Sponsor:

Description (last modified by karsten)

One goal we would like to work on for SponsorF year3 is the very hard topic of getting Tor to handle datagram end-to-end -- which may not even be on the roadmap depending on which of Steven's transport approaches we end up liking. An alternative approach would be to make/modify VoIP applications to work better on Tor (#5700).

Child Tickets

Change History (15)

comment:1 Changed 7 years ago by karsten

Description: modified (diff)
Type: defectproject

comment:2 Changed 7 years ago by karsten

Keywords: SponsorZ added
Milestone: Sponsor Z: March 1, 2013

Switching from using milestones to keywords for sponsor deliverables. See #6365 for details.

comment:3 Changed 7 years ago by T(A)ILS developers

Cc: tails@… added

comment:4 Changed 7 years ago by proper

Cc: adrelanos@… added

comment:5 Changed 7 years ago by mo

Cc: mo added

comment:6 Changed 7 years ago by mikeperry

See #5707. I think that will give us the performance we need to make this tolerable.

comment:7 Changed 6 years ago by mttp

Owner: set to mttp, Phoul
Status: newassigned

comment:8 Changed 6 years ago by mttp

Phoul and I have written a guide on using Mumble with Tor. See: https://trac.torproject.org/projects/tor/wiki/doc/TorifyHOWTO/Mumble

comment:9 Changed 6 years ago by mttp

Keywords: SponsorF added
Owner: changed from mttp, Phoul to mttp

comment:10 in reply to:  9 Changed 6 years ago by mttp

Replying to mttp:

(It turns out you can't assign a ticket to multiple people.)

comment:11 Changed 6 years ago by mttp

Another VoIP client that might be worth investigating is Jitsi: https://jitsi.org. Jitsi supports XMPP and a number of other protocols. It also supports video chat.

comment:12 Changed 6 years ago by phoul

Cc: admin@… added

comment:13 in reply to:  11 Changed 6 years ago by mttp

Replying to mttp:

Another VoIP client that might be worth investigating is Jitsi: https://jitsi.org.

This ticket remains open on Jitsi's website: https://trac.jitsi.org/ticket/1060 "Jitsi leaks DNS when using a proxy"

comment:14 in reply to:  8 Changed 6 years ago by mttp

Replying to mttp:

Phoul and I have written a guide on using Mumble with Tor. See: https://trac.torproject.org/projects/tor/wiki/doc/TorifyHOWTO/Mumble

Mumble can send voice and chat data over Tor via an AES-256 encrypted TCP stream. This works well when Mumble is used with Torsocks.

One issue we encountered was that when Mumble uses the native proxy settings to connect to Tor, the hostnames of the listed Mumble servers get resolved by the local DNS servers. Mumble uses a Bonjour-style multicast system to resolve the hostnames of possibly hundreds of Mumble servers around the world very quickly right when the program launches. When Torsocks is used, all of this traffic just gets dropped because it's UDP. If you were planning on browsing through a bunch of game servers and deciding if you want to join them, this might be a problem for you. If you already know of a mumble server you wanted to use (either an IP address or a hostname) then you don't lose anything by using Torsocks instead of the local proxy settings.

If you use Windows, torsocks is not available to you. Using the local proxy settings still might not be a problem if you know the IP address of the Mumble server you want to connect to because no DNS resolution is done for that IP. An observer could see you were using Mumble but not who you were talking to. If you use Windows and you have the hostname of the Mumble server you want to use, use tor-resolve to get an IP address before you give it to Mumble. If the hostname is an onion address, the onion address will get resolved by your local ISP, which is pretty bad for you.

I tested Mumble with Torcap and Tortilla on Windows. The Mumble DNS multicast bypassed Torcap's proxy settings, basically leaving the same problem as using the native proxy settings. Tortilla requires using a Virtual Machine. For me, using Tortilla introduced intolerable amounts of latency into the connection. Maybe someone with a whole lot of RAM can get better results using Mumble with Tortilla, I don't know. For me neither of these tools provided a solution.

Right now using Mumble safely with Tor requires torsocks.

Closing this ticket unless anyone objects.

comment:15 Changed 6 years ago by mttp

Resolution: fixed
Status: assignedclosed
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