- tor-dev - lists.torproject.org

Have the Tor daemon use more cores
by Jeremy 03 Dec '15

03 Dec '15

>> I've been working on the volunteer project described here >> >https://www.torproject.org/getinvolved/volunteer.html.en#useMoreCores but >> >can't spend much more time on it. >> > >> >Right now, I have refactored circuit_receive_relay_cell() in relay.c (which >> >calls relay_crypt() and eventually the AES crypt routines) to use the >> >workqueue.c infrastructure similar to cpuworker.c. >> > >> >When the refactored code runs in single threaded mode, all seems good. Once >> >I activate the thread pool and start sending it work with >> >threadpool_queue_work(), it Bootstraps 100% okay and runs for several >> >minutes before crashing on cells it doesn't handle properly. >> > >> >I'm happy to share my code with anyone interested. > Hi Jeremy! > > This is great! Thanks for this. You should definitely post your code (link to > branch or .diff) to ticket #7572 [1] so someone at some point can take a look > at it and help you out. > > Thanks! > David > > [1]https://trac.torproject.org/projects/tor/ticket/7572 > Thank you. I have posted my code and tried to explain my thought process on ticket #7572.

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Scaling Tor Metrics
by Karsten Loesing 01 Dec '15

01 Dec '15

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hello devs, the Tor Metrics website [0] claims to be "the primary place to learn interesting facts about the Tor network" and invites its visitors who "come across something that is missing" to contact the website authors about it. That's a bold statement I put there! :) Yet, there's considerable product backlog with possible enhancements [1] that doesn't seem to ever become shorter. Even worse, it can be expected that the backlog will refill quickly once the community notices that feature requests are suddenly considered. The main reason for this unfortunate situation is that Tor Metrics contains many moving parts, including some heavy database lifting that takes place below the surface, that all want to be maintained. Adding more parts just makes the whole thing even more likely to break. At the same time, knowing about the situation that Tor Metrics has become almost closed to contributions is painful. This posting shall discuss possible solutions. The goal is to let Tor Metrics grow in a healthy fashion that encourages contributions from the community. These solutions are not mutually exclusive, and the best solution may use parts of more than one solution sketched out here. 1 Make Tor Metrics better and bigger, internally The obvious solution is that the maintainers of Tor Metrics could just work harder to overcome the problems stated above. Let's think this through. 1.1 Add more development resources If only the current Tor Metrics maintainers had more time to devote to cleaning up existing parts and to add new parts, that would solve our problem. They could refactor parts that are hard to maintain, and they could work off the serious backlog that has piled up. Of course, this means dropping or handing over responsibilities for other products, and it may mean finding (and paying) new developers to help maintain Tor Metrics. It's unclear whether anything like this would fit into Tor's budget, and whether these changed priorities would make users of tools that had to be dropped or handed over unhappy. 1.2 Rewrite internal parts of Tor Metrics to encourage external contributions Most of Tor Metrics would have run 10 or 15 years ago with only minor modifications. It's not necessarily a bad thing to use established technologies. But maybe, if we rewrite it using modern data-processing, web, and visualization frameworks, it becomes more attractive to other developers to contribute code and help maintain existing (well, then rewritten) code. The result would be a larger Tor Metrics website that is easier to maintain and hopefully maintained by more people. It's unclear how realistic this plan is, though, and it requires attention by Tor Metrics maintainers to bring it enough into shape for external contributors to get involved. 2 Add more ways to contribute to Tor Metrics externally It may be possible to further grow Tor Metrics without adding more code to it, hence not making it any harder to maintain. However, if code to generate visualizations is run elsewhere, there's a certain risk that results are not perceived as trustworthy as if that code were run as part of Metrics. This is primarily a problem of setting user expectations right. We could add different ways for contributing to Tor Metrics, depending on the level of commitment that contributors are willing to make. Possible new ways (in addition to filing a Trac ticket, which is already possible, though not very effective) are: 2.1 Accept contribution of static data or static graphs Somebody might contribute data (in a tarball, download link, etc.) or a static graph (static as in "doesn't break, ever", not "static HTML with a tiny amount of JavaScript that will surely never break"). The Tor Metrics team reviews that and puts it on the Tor Metrics website, together with a short description, author information, license, etc. There are plenty of visualizations on Trac and on the mailing lists, so we'll have to define criteria what we add and what not, and we'll need a good process for making that happen. 2.2 Link to external websites Somebody might write a website that visualizes Tor network data. The Tor Metrics team reviews the idea behind it, but not necessarily look at its code, and adds an external link to Tor Metrics. It becomes obvious that the authors remain responsible for their visualization, so there's no risk involved for Tor Metrics, but users may not trust it as much, because it doesn't have the Tor Metrics label. Note that we're already doing this approach by linking to the visualizations showing "Tor users as percentage of larger Internet population" [2] and "Data flow in the Tor network" [3]. Also note that we could as well have hosted the former directly on Tor Metrics with appropriate attribution, because it's a static image. This is not the case with the latter. 2.3 Run an externally developed website as if it were part of Tor Metrics Let's imagine that somebody produces a visualization of Tor network data and would like to make it part of Tor Metrics but without limiting themselves to the technology used by Tor Metrics. We could let them write their visualization as website and integrate it into Tor Metrics after reviewing its code. Technically, part of this integration would be to "redress" the website by applying the Tor Metrics design (which has lots of room for improvement, but let's just say the result will look as seamlessly integrated into Tor Metrics as the "Network bubble graphs" [4]). Another part would probably be to rewrite web requests, so that users still think they're talking to https://metrics.torproject.org/, but really they're talking to another webserver behind that. Regarding hosting and maintenance, in theory, the website could be hosted by the original creators, but that effectively means that the Tor Metrics team gives up part of the control about what's on the Tor Metrics website. The creators of the external website could change parts or add new parts that wouldn't be reviewed by Tor Metrics developers, but they would be perceived as part of Metrics, which seems bad. The Tor Metrics team could run the externally developed website on a separate host or on the same host as Tor Metrics. We could imagine variants where the original creator stays around to fix any issues as they come up, or we could imagine that they donate their visualization that the Tor Metrics people will then maintain. We could even imagine that the Tor Metrics maintainers some day decide to integrate the originally external website into Tor Metrics proper, but that would not be required for this model to work. All these ideas require writing down guidelines, criteria, and processes. In particular, they require more thoughts and input from other people who are not currently involved in Tor Metrics maintenance and who can be expected more objective. And once these ideas are implemented, we'll need more Tor Metrics maintainer than just one. What are your thoughts? All the best, Karsten [0] https://metrics.torproject.org/ [1] https://trac.torproject.org/projects/tor/query?status=!closed&component=Met… [2] https://metrics.torproject.org/oxford-anonymous-internet.html [3] https://metrics.torproject.org/uncharted-data-flow.html [4] https://metrics.torproject.org/bubbles.html -----BEGIN PGP SIGNATURE----- Comment: GPGTools - http://gpgtools.org iQEcBAEBAgAGBQJWVdmJAAoJEJD5dJfVqbCrmlEH/j6IjRNEkXzRVJBIBcFMKIwR eAA958Zg+DCzKPHI6Y7KZ/jGCHMP21r+YGIFevbJV4LDos9D2G0RP681/5PK7/dW if4Pz0xhl/LqbhLoOSqU2wGJG+GdWgjuTxO1TBMPUhYK71lwJsZ0cUzbNee7iAqJ zjdl3W3o4XJma0ZjZFH/gVVPbemvQHftrO8d0v7L2gFHfXmJg0kEwSZ4lJW0hfOx wIizEadFSx9/7CrINvbcHbyck0N+DRSfRYyMNSjpyFbnYI7HjYk7/+jvLWALEYZT 0MZbuL/zl/PFpkTDNY0jzE5fPaKjtS2pEoZn85Wn1+0kCjeFLE/Hvulvn6ZFxsA= =n5p1 -----END PGP SIGNATURE-----

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Have the Tor daemon use more cores
by Jeremy 01 Dec '15

01 Dec '15

I've been working on the volunteer project described here https://www.torproject.org/getinvolved/volunteer.html.en#useMoreCores but can't spend much more time on it. Right now, I have refactored circuit_receive_relay_cell() in relay.c (which calls relay_crypt() and eventually the AES crypt routines) to use the workqueue.c infrastructure similar to cpuworker.c. When the refactored code runs in single threaded mode, all seems good. Once I activate the thread pool and start sending it work with threadpool_queue_work(), it Bootstraps 100% okay and runs for several minutes before crashing on cells it doesn't handle properly. I'm happy to share my code with anyone interested. Thanks.

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BridgeDB 0.3.4 is released
by isis 01 Dec '15

01 Dec '15

Hey, I've just tagged and released BridgeDB 0.3.4. For those interested, here are the changes (c.f. https://gitweb.torproject.org/bridgedb.git/tree/CHANGELOG) Changes in version 0.3.4 - 0.3.5 - 2015-11-30 * FIXES #14685 https://bugs.torproject.org/14685 This disables distribution of obfs2 bridges. This pluggable transport has known distiguishers which allow adversaries to identify client connections to obfs2 bridges, which in turn allows these connections to be blocked/censored. With numerous obfs3 and obfs4 bridges both readily available, users should not be presented with an easily-configurable choice that is known to be unsafe for the majority of users. And includes the following general changes: * ADDS error pages to BridgeDB's web interface, to provide friendlier explanations for downtime, missing pages, and internal server errors. For example: https://bridges.torproject.org/404 -- ♥Ⓐ isis agora lovecruft _________________________________________________________ OpenPGP: 4096R/0A6A58A14B5946ABDE18E207A3ADB67A2CDB8B35 Current Keys: https://blog.patternsinthevoid.net/isis.txt

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[Applications Team] Meeting next Tuesday 19:00 UTC
by Georg Koppen 01 Dec '15

01 Dec '15

Hi, just a reminder that the applications team is having its monthly meeting next week on Tuesday, December 1 at 19:00 UTC in #tor-project on irc.oftc.net. There is no proposed topic for this meeting yet. Please come up with suggestions if you feel there is something we should discuss. See you there, Georg

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BridgeDB 0.3.3 is released
by isis 01 Dec '15

01 Dec '15

Hello! I released BridgeDB 0.3.3 a few weeks ago, and deployed it on the production server. However, I completely forgot to email the list to notify you all of the changes. Oops, sorry! For those who are curious, BridgeDB-0.3.3 brought about the following changes (and, as always, the current changelog is available at https://gitweb.torproject.org/bridgedb.git/tree/CHANGELOG) Changes in version 0.3.3 - 2015-10-25 * FIXES #12029 https://bugs.torproject.org/12029 BridgeDB now has an API for creating Bridge Distributors. See the bridgedb.distribute module, or its developer documentation at https://pythonhosted.org/bridgedb/bridgedb.distribute.html. * FIXES PART OF #12506 https://bugs.torproject.org/12506 BridgeDB's two Distributors (HTTPS and Email) are now entirely modularised and self-contained within separate subdirectories in the source code. This is the first step to redesigning these Distributors into their own separate processes, which will allow the Distributors to remain functional while BridgeDB is reparsing bridge descriptors. * FIXES #15968 https://bugs.torproject.org/15968 BridgeDB now sends a Content-Security-Policy header which explicitly allows Javascript, images, CSS, and fonts, from https://bridges.torproject.org. All other types of content are forbidden, including: - embedding https://bridges.torproject.org within <iframe>, <embed>, or <object>, and attempting to source additional resources into its embedded context - inline Javascript, including Javascript within SVG files - inline CSS - externally hosted fonts - inline SVG, e.g. via the HTML5 <svg> tag - any and all connections made via Javascript XMLHttpRequests, WebSockets, sendBeacon(), and Web Workers - plugins - applets BridgeDB's Content-Security-Policy does not yet make use of certain newer, lesser supported, Content-Security-Policy v2.0 directives, such as "reflected-xss" and "frame-ancestors", but may someday. * FIXES #16273 https://bugs.torproject.org/16273 Several links to Tor Project gitweb URLs within the developer documentation were outdated in that they still used the old gitweb URL format. These are now updated. Thanks to David Fifield for the bug report and patches. * FIXES #16330 https://bugs.torproject.org/16330 BridgeDB can now handle bridge-server-descriptors with extra-info-digest fields which have two values, as well as both bridge-server-descriptors and bridge-extrainfo descriptors which contain Ed25519 key material and signatures. See Tor proposals #220 and #228 for more information on the changes to these descriptors. Note that BridgeDB can now parse this information, but does not yet make use of any Ed25519 cryptographic material within bridge descriptors. https://gitweb.torproject.org/torspec.git/tree/proposals/220-ecc-id-keys.txt https://gitweb.torproject.org/torspec.git/tree/proposals/228-cross-certific… Thanks to Atagar for patching Stem. * FIXES #16616 https://bugs.torproject.org/16616 The HSDir flag can now be included within bridge-networkstatus documents. BridgeDB now has unittests which guarantee that its parsers safely ignore this flag, as well as any flags unknown to BridgeDB which may appear in the future. Thanks to Roger Dingledine for alerting me about the change. * FIXES #16649 https://bugs.torproject.org/16649 Mobile users, and other users with small screen pixel ratios, will find that the UI of BridgeDB's HTTPS Distributor has greatly increased in usability and readability. And includes the following general changes: * FIXES an error when requesting the non-HTML version of the bridges page (e.g. https://bridges.torproject.org/bridges?format=plain) * REMOVES the `bridgedb test` commandline option. BridgeDB's tests can be run via `python setup.py test` or `make test` (or `make coverage` for generating HTML test coverage statistics). * CHANGES the HTTPS Distributor to HTML-encode Bridge Lines. Previously, a malicious Pluggable Transport Bridge could include in its PT arguments something like "evil=<script>[…]</script>" and if such a Bridge were to be distributed to a user, that user's web browser would execute the script (if Javacript was enabled). Other characters, including non-ASCII, control characters, double quotes, and backslashes, are also sanitised from Bridge Lines. Thanks to Robert Ransom for the patches. * CHANGES BridgeDB's module/package version numbers to be compliant with PEP440. * CHANGES the layout of BridgeDB's source code directories. Rather than storing BridgeDB's source in "lib/bridgedb/", it is now kept in "bridgedb/". Similarly, the directory containing BridgeDB's tests has been moved from "lib/bridgedb/test/" to "test/", which means that the tests are no longer installed when running `python setup.py install` or `make install`. * ADDS several improvements to the developer documentation at https://pythonhosted.org/bridgedb. * UPDATE English (en_US) translations. * UPDATE English (en) translations. * ADD Serbian (sr) translations. Thanks to obj.petit.a, Ivan Radeljic, and Milenko Doder. * UPDATE Arabic (ar) translations. Thanks to A. Hassan, debo debo, KACIMI LAMINE, and Nudroid A. * UPDATE Catalan (ca) translations. Thanks to laia_. * UPDATE Czech (cs) translations. Thanks to Tomas Palik and Vlastimil Burián. * UPDATE Danish (da) translations. Thanks to Mogelbjerg. * UPDATE German (de) translations. Thanks to jschfr, Junge Limba, and Toralf Förster. * UPDATE English (en_GB) translations. Thanks to Andi Chandler. * UPDATE Farsi (fa) translations. Thanks to some awesome anonymous person for helping out. * UPDATE Finish (fi) translations. Thanks to Riku Viitanen. * UPDATE French (fr) translations. Thanks to elouann, Trans-fr, and Towinet. * UPDATE French (fr_CA) translations. Thanks to Trans-fr. * UPDATE Croatian (hr_HR) translations. Thanks to some awesome anonymous person for helping out. * UPDATE Hungarian (hu) translations. Thanks to some awesome anonymous person for helping out. * UPDATE Indonesian (id) translations. Thanks to Anthony Santana, Astryd Viandila Dahlan, cholif yulian, constantius damar wicaksono, Dwi Cahyono, L1Nus, km242saya, and Zamani Karmana. * UPDATE Italian (it) translations. Thanks to Random_R. * UPDATE Japanese (ja) translations. Thanks to ABE Tsunehiko. * UPDATE Latvian (lv) translations. Thanks to Ojārs Balcers. * UPDATE Norwegian Bokmål (nb) translations. Thanks to Erik Matson and Kristian Andre Henriksen. * UPDATE Dutch (nl) translations. Thanks to Mart3000. * UPDATE Polish (pl) translations. Thanks to Karol Obartuch. * UPDATE Portuguese (pt) translations. Thanks to Bruno D. Rodrigues and MMSRS. * UPDATE Brazillian Portuguese (pt_BR) translations. Thanks to Communia. * UPDATE Romanian (ro) translations. Thanks to Ana, axel_89, and Di N. * UPDATE Russian (ru) translations. Thanks to Ivan. * UPDATE Slovak (sk_SK) translations. Thanks to StefanH. * UPDATE Albanian (sq) translations. Thanks to some awesome unknown anonymous person who didn't add their name to the list of translators. * UPDATE Swedish (sv) translations. Thanks to Peter Michanek. * UPDATE Turkish (tr) translations. Thanks to Bullgeschichte and Fomas. * UPDATE Ukranian (uk) translations. Thanks to Yasha. * UPDATE Chinese Mandarin (zh_CN) translations. Thanks to khi. * UPDATE Taiwanese Mandarin (zh_TW) translations. Thanks to x4r. -- ♥Ⓐ isis agora lovecruft _________________________________________________________ OpenPGP: 4096R/0A6A58A14B5946ABDE18E207A3ADB67A2CDB8B35 Current Keys: https://blog.patternsinthevoid.net/isis.txt

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Summary of meek's costs, October 2015
by David Fifield 29 Nov '15

29 Nov '15

Here's the summary of meek's CDN fees for October 2015. App Engine + Amazon + Azure = total by month February 2014 $0.09 + -- + -- = $0.09 March 2014 $0.00 + -- + -- = $0.00 April 2014 $0.73 + -- + -- = $0.73 May 2014 $0.69 + -- + -- = $0.69 June 2014 $0.65 + -- + -- = $0.65 July 2014 $0.56 + $0.00 + -- = $0.56 August 2014 $1.56 + $3.10 + -- = $4.66 September 2014 $4.02 + $4.59 + $0.00 = $8.61 October 2014 $40.85 + $130.29 + $0.00 = $171.14 November 2014 $224.67 + $362.60 + $0.00 = $587.27 December 2014 $326.81 + $417.31 + $0.00 = $744.12 January 2015 $464.37 + $669.02 + $0.00 = $1133.39 February 2015 $650.53 + $604.83 + $0.00 = $1255.36 March 2015 $690.29 + $815.68 + $0.00 = $1505.97 April 2015 $886.43 + $785.37 + $0.00 = $1671.80 May 2015 $871.64 + $896.39 + $0.00 = $1768.03 June 2015 $601.83 + $820.00 + $0.00 = $1421.83 July 2015 $732.01 + $837.08 + $0.00 = $1569.09 August 2015 $656.76 + $819.59 + $154.89 = $1631.24 September 2015 $617.08 + $710.75 + $490.58 = $1818.41 October 2015 $672.01 + $110.72 + $300.64 = $1083.37 -- total by CDN $7443.58 + $7987.32 + $946.11 = $16377.01 grand total https://metrics.torproject.org/userstats-bridge-transport.html?graph=userst… In October we had about 4,000 simultaneous users all month. There was an unfortunate outage of meek-amazon (not the result of censorship, just operations failure). Between 30 September and 9 October the bridge had an expired HTTPS certificate. [tor-talk] Outage of meek-amazon https://lists.torproject.org/pipermail/tor-talk/2015-October/039231.html https://lists.torproject.org/pipermail/tor-talk/2015-October/039234.html And then, as a side effect of installing a new certificate, the bridge's fingerprint changed, which caused Tor Browser to refuse to connect. It used to be that we didn't include fingerprints for the meek bridges, but now we do, so we didn't anticipate this error and didn't notice it quickly. Update the meek-amazon fingerprint to B9E7141C594AF25699E0079C1F0146F409495296 https://trac.torproject.org/projects/tor/ticket/17473 [tor-talk] Changed fingerprint for meek-amazon bridge (attn support) https://lists.torproject.org/pipermail/tor-talk/2015-November/039397.html Interestingly, the meek-amazon bridge still had about 400 simultaneous users (not as much as normal) during the time when the fingerprint didn't match. I would have expected it to go almost to zero. Maybe it's people using an old version of Tor Browser (from before March 2015) or some non–Tor Browser installation. Our grant for meek-azure ran out and now it costs money. Accordingly I've rate-limited it to limit costs. I set it to 1.1 MB/s on 2 October and to 0.8 MB/s on 30 October. [tor-talk] meek-azure now rate-limited https://lists.torproject.org/pipermail/tor-talk/2015-October/039169.html meek-google was also out for a few days around 30 October because I messed up the app upload and pointed it to the wrong bridge. If you want to set up your own bridge and CDN instance without rate limiting, I can help you do it. Here are some docs to look at: https://trac.torproject.org/projects/tor/wiki/doc/meek#Howtorunameek-server… https://trac.torproject.org/projects/tor/wiki/doc/meek#GoogleAppEngine https://trac.torproject.org/projects/tor/wiki/doc/meek#AmazonCloudFront https://trac.torproject.org/projects/tor/wiki/doc/meek#MicrosoftAzure == App Engine a.k.a. meek-google == Here is how the Google costs broke down: 2842 GB $341.06 6619 instance hours $330.95 Compared to the previous month: 2871 GB $344.53 5451 instance hours $272.55 https://globe.torproject.org/#/bridge/88F745840F47CE0C6A4FE61D827950B06F9E4… == Amazon a.k.a. meek-amazon == Usage of meek-amazon was quite low this month because of bridge outages having to do with an expired HTTPS certificate and a changed relay fingerprint. Asia Pacific (Singapore) 6M requests $8.24 36 GB $5.05 Asia Pacific (Sydney) 635K requests $0.79 1 GB $0.21 Asia Pacific (Tokyo) 1M requests $1.71 5 GB $0.71 EU (Ireland) 39M requests $46.81 130 GB $9.97 South America (Sao Paulo) 2M requests $4.98 5 GB $1.23 US East (Northern Virginia) 24M requests $24.36 86 GB $6.64 -- total 74M requests $86.89 266 GB $23.81 https://globe.torproject.org/#/bridge/F4AD82B2032EDEF6C02C5A529C42CFAFE5165… (Note new fingerprint.) == Azure a.k.a. meek-azure == Zone 1 1652 GB $202.51 Zone 2 586 GB $98.13 -- total 2238 GB $300.64 https://globe.torproject.org/#/bridge/AA033EEB61601B2B7312D89B62AAA23DC3ED8… Earlier reports in this series: https://lists.torproject.org/pipermail/tor-dev/2014-August/007429.html https://lists.torproject.org/pipermail/tor-dev/2014-October/007576.html https://lists.torproject.org/pipermail/tor-dev/2014-November/007716.html https://lists.torproject.org/pipermail/tor-dev/2014-December/007916.html https://lists.torproject.org/pipermail/tor-dev/2015-January/008082.html https://lists.torproject.org/pipermail/tor-dev/2015-February/008235.html https://lists.torproject.org/pipermail/tor-dev/2015-March/008427.html https://lists.torproject.org/pipermail/tor-dev/2015-April/008596.html https://lists.torproject.org/pipermail/tor-dev/2015-May/008767.html https://lists.torproject.org/pipermail/tor-dev/2015-June/008932.html https://lists.torproject.org/pipermail/tor-dev/2015-July/009030.html https://lists.torproject.org/pipermail/tor-dev/2015-August/009213.html https://lists.torproject.org/pipermail/tor-dev/2015-September/009533.html https://lists.torproject.org/pipermail/tor-dev/2015-October/009672.html

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does renewing ed25519 signing key hurt if done to often?
by nusenu 28 Nov '15

28 Nov '15

Hi, I'm wondering if it does any bad if ed25519 online keys are renewed (to) often (i.e. on every ansible-playbook run and the admin runs it 3 times in a row to get it to complete on all hosts). If key renewal causes all existing connections to die I'll try to workaround the problem and make tor --keygen idempotent (replace the key only if its expiry changed).

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tor weather warning tor ops about expiring signing keys?
by nusenu 28 Nov '15

28 Nov '15

Hi, I'm wondering if a service like a future tor weather could have an additional check to warn relay ops about key expiry: (something like "Email me when the router's signing key is about to expire") Do relays disclose the fact that they are run via OfflineMasterKey 1? Do dir auths/tor clients see when a currently used signing key is about to expire? thanks

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documentation for new offline master key functionality (--keygen is undocumented)
by nusenu 28 Nov '15

28 Nov '15

Hi, since tor 0.2.7.5 is apparently not very far [1] from being released I was wondering whether there is any documentation about the new offline master key functionality? (or is this undocumented because it is not considered for general use yet?) tor v0.2.7.4-rc's manual has the following: " SigningKeyLifetime N days|weeks|months For how long should each Ed25519 signing key be valid? Tor uses a permanent master identity key that can be kept offline, and periodically generates new "signing" keys that it uses online. This option configures their lifetime. (Default: 30 days) OfflineMasterKey 0|1 If non-zero, the Tor relay will never generate or load its master secret key. Instead, you’ll have to use "tor --keygen" to manage the master secret key. (Default: 0) " but doesn't say anything about --keygen itself [2]. The 0.2.7.x mentions also a '--newpass' option that I wasn't able to find in the manpage: " - Add a new OfflineMasterKey option to tell Tor never to try loading or generating a secret Ed25519 identity key. You can use this in combination with tor --keygen to manage offline and/or encrypted Ed25519 keys. Implements ticket 16944. - Add a --newpass option to allow changing or removing the passphrase of an encrypted key with tor --keygen. Implements part of ticket 16769. - On receiving a HUP signal, check to see whether the Ed25519 signing key has changed, and reload it if so. Closes ticket 16790. " Can a tor operator use one offline master key for several relays (that are running at the same time) or is one master key required for every relay? (I assume the latter) How does the process of renewing the signing keys look like? According to the logs I assume simple run tor --keygen again and copy ed25519_signing_cert + ed25519_signing_secret_key to the relay's /keys folder the logs say: "It looks like I need to generate and sign a new medium-term signing key, because you asked me to make one with --keygen. To do that, I need to load the permanent master identity key." Does a tor operator has to SIGHUP a running tor instance after copying the new signing keys to the appropriate folder or will tor attempt to reload that file as soon as this signing key expires? How can a tor relay op display a given signing key's expiry date? Does using the offline master key functionality imply that the relay will only have an ed25519 and no RSA key? Is the offline master key limited to ed25519 keys and useless while using ed25519 + RSA keys at the same time? (because the RSA key is not offline?) thanks! [1] https://lists.torproject.org/pipermail/tor-consensus-health/2015-November/0… [2] https://trac.torproject.org/projects/tor/ticket/17583

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