Serveis Onion

How do I know if I'm using v2 or v3 onion services?

You can identify v3 onion addresses by their 56 character length, e.g. Tor Project's v2 address:http://expyuzz4wqqyqhjn.onion/, and Tor Project's v3 address: http://2gzyxa5ihm7nsggfxnu52rck2vv4rvmdlkiu3zzui5du4xyclen53wid.onion/

If you're an onion service administrator, you must upgrade to v3 onion services as soon as possible. If you're a user, please ensure that you update your bookmarks to the website's v3 onion addresses.

What is the timeline for the v2 deprecation?

In September 2020, Tor started warning onion service operators and clients that v2 will be deprecated and obsolete in version 0.4.6. Tor Browser started warning users in June, 2021.

In July 2021, 0.4.6 Tor will no longer support v2 and support will be removed from the code base.

In October 2021, we will release new Tor client stable versions for all supported series that will disable v2.

You can read more in the Tor Project's blog post Onion Service version 2 deprecation timeline.

Can I keep using my v2 onion address? Can I access my v2 onion after September? Is this a backward-incompatible change?

V2 onion addresses are fundamentally insecure. If you have a v2 onion, we recommend you migrate now. This is a backward incompatible change: v2 onion services will not be reachable after September 2021.

What is the recommendation for developers to migrate? Any tips on how to spread the new v3 addresses to people?

In torrc, to create a version 3 address, you simply need to create a new service just as you did your v2 service, with these two lines:

HiddenServiceDir /full/path/to/your/new/v3/directory/
HiddenServicePort <virtual port> <target-address>:<target-port>

The default version is now set to 3 so you don't need to explicitly set it. Restart tor, and look on your directory for the new address. If you wish to keep running your version 2 service until it is deprecated to provide a transition path to your users, add this line to the configuration block of your version 2 service:

HiddenServiceVersion 2

This will allow you to identify in your configuration file which one is which version.

If you have Onion-Location configured on your website, you need to set the header with your new v3 address. For technical documentation about running onion services, please read the Onion Services page in our Community portal.

I didn't see the announcement, can I get more time to migrate?

No, v2 onion connections will start failing nowish, first slowly, then suddenly. It's time to move away.

Will services start failing to be reached in September, or before already?

Already, introduction points are not in Tor 0.4.6 anymore, so they will not be reachable if relay operators update.

As a website administrator, can I redirect users from my v2 onion to v3?

Yes, it will work until the v2 onion address is unreachable. You may want to encourage users to update their bookmarks.

Are v3 onion services going to help in mitigating DDoS problems?

Yes, we are continuously working on improving onion services security. Some of the work we have in our roadmap is ESTABLISH_INTRO Cell DoS Defense Extension, Res tokens: Anonymous Credentials for Onion Service DoS Resilience, and A First Take at PoW Over Introduction Circuits. For an overview about these proposals, read the detailed blog post How to stop the onion denial (of service).

When browsing an Onion Service, Tor Browser displays different onion icons in the address bar indicating the security of the current webpage.

Image of an onion An onion means:

  • The Onion Service is served over HTTP, or HTTPS with a CA-Issued certificate.
  • The Onion Service is served over HTTPS with a Self-Signed certificate.

Image of an onion with a red slash An onion with a red slash means:

  • The Onion Service is served with a script from an insecure URL.

Image of an onion with a caution sign An onion with caution sign means:

  • The Onion Service is served over HTTPS with an expired Certificate.
  • The Onion Service is served over HTTPS with a wrong Domain.
  • The Onion Service is served with a mixed form over an insecure URL.

If you cannot reach the onion service you desire, make sure that you have entered the 16-character or, the newest format, 56-character onion address correctly; even a small mistake will stop Tor Browser from being able to reach the site. Si encara no podeu connectar-vos al servei de onion, torneu-ho a provar més tard. És possible que hi hagi un problema de connexió temporal o que els operadors del lloc hagin permès que es desconnectés sense previ avís.

You can also ensure that you're able to access other onion services by connecting to DuckDuckGo's onion service.

Els serveis de onion permeten que la gent navegui, però també publiqui de manera anònima, inclosa la publicació de llocs web anònims.

Els serveis de onion també es basen en el xat i l'intercanvi d'arxius sense metadades, una interacció més segura entre els periodistes i les seves fonts, com ara SecureDrop o OnionShare, actualitzacions de programari més segures i formes més segures d'arribar a llocs web populars com Facebook.

These services use the special-use top level domain (TLD) .onion (instead of .com, .net, .org, etc.) and are only accessible through the Tor network.

When accessing a website that uses an onion service, Tor Browser will show at the URL bar an icon of an onion displaying the state of your connection: secure and using an onion service.

Onion icon

Els llocs web que només són accessibles per Tor són els anomenats "onions" i finalitzen en el TLD .onion. For example, the DuckDuckGo onion is https://duckduckgogg42xjoc72x3sjasowoarfbgcmvfimaftt6twagswzczad.onion/. Podeu accedir a aquests llocs web utilitzant el navegador Tor. Les adreces han de ser compartides amb vostè per l'amfitrió del lloc web, ja que les onions no estan indexades en els motors de cerca de la manera típica que tenen els llocs web de vanilla.

Onion-Location is a new HTTP header that web sites can use to advertise their onion counterpart. If the web site that you're visiting has an onion site available, a purple suggestion pill will prompt at the URL bar saying ".onion available". When you click on ".onion available", the web site will be reloaded and redirected to its onion counterpart. At the moment, Onion-Location is available for Tor Browser desktop (Windows, macOS and GNU/Linux). You can learn more about Onion-Location in the Tor Browser Manual. If you're an onion service operator, learn how to configure Onion-Location in your onion site.

An authenticated onion service is an onion service that requires you to provide an authentication token (in this case, a private key) before accessing the service. The private key is not transmitted to the service, and it's only used to decrypt its descriptor locally. You can get the access credentials from the onion service operator. Reach out to the operator and request access. Learn more about how to use onion authentication in Tor Browser. If you want to create an onion service with client authentication, please see the Client Authorization in the Community portal.