prop224: Implement stealth client authorization

prop224 currently does not specify stealth client authorization.

This is a feature from rend-spec.txt which makes the HS create a unique onion address for each authorized client. This way revoked clients cannot get presense information about the hidden service, since they don't know the onion addresses of other clients.

This is useful for cases where authorized clients have a chance of turning adversarial and there is a need for total revocation.

tl;dr: We need to specify stealth auth in prop224, and implement it.

changed milestone to %Tor: unspecified in legacy/trac

moved from tor#20742 (moved)

added 035-removed in Legacy / Trac client-authorization in Legacy / Trac component::core tor/tor in Legacy / Trac hs-auth in Legacy / Trac milestone::Tor: unspecified in Legacy / Trac needs-proposal in Legacy / Trac owner::asn in Legacy / Trac points::3 in Legacy / Trac priority::very high in Legacy / Trac prop224 in Legacy / Trac prop224-extra in Legacy / Trac severity::normal in Legacy / Trac sponsor::R-can in Legacy / Trac status::assigned in Legacy / Trac stealth-authorization in Legacy / Trac term-project in Legacy / Trac tor-hs in Legacy / Trac type::enhancement in Legacy / Trac labels

Trac:
Keywords: N/A deleted, needs-proposal added
Milestone: N/A to Tor: 0.3.???
Component: - Select a component to Core Tor/Tor

This keyword indicate that it is a nice extra feature to have for prop224 but not needed for the minimal viable implementation.

Trac:
Keywords: N/A deleted, prop224-extra added

Trac:
Milestone: Tor: 0.3.??? to Tor: 0.3.1.x-final

Trac:
Milestone: Tor: 0.3.1.x-final to Tor: 0.3.2.x-final
Status: new to assigned
Owner: N/A to asn

Trac:
Keywords: N/A deleted, tor-hs added

Prioritize prop224 tickets for 031 milestone. They are all "Enhancement".

Trac:
Type: task to enhancement
Priority: Medium to Very High

We can't make those for 032 so for now they go in Unspecified.

Trac:
Milestone: Tor: 0.3.2.x-final to Tor: unspecified

Trac:
Keywords: N/A deleted, term-project, client-authorization sealth-authorization added

Trac:
Username: pege
Cc: N/A to peter@arbitrary.ch

Trac:
Cc: peter@arbitrary.ch to peter@arbitrary.ch, dmr

Trac:
Keywords: client-authorization sealth-authorization deleted, client-authorization stealth-authorization added

Adding this to 0.3.5 because its parent is there, but we can remove this if nobody is doing it.

Trac:
Keywords: term-project deleted, term-project 035-roadmap-subtask added
Milestone: Tor: unspecified to Tor: 0.3.5.x-final

Removing this from 035 because no one is doing it and there is no chance it will happen in 035 timeframe.

Trac:
Keywords: term-project 035-roadmap-subtask deleted, term-project added
Milestone: Tor: 0.3.5.x-final to Tor: unspecified

Trac:
Keywords: term-project deleted, term-project 035-removed added

Removing parent, stealth authorization is something else compared to the "descriptor" authorization.

Trac:
Parent: legacy/trac#20700 (moved) to N/A

Let onion service authorization related tickets know of each other.

https://gitweb.torproject.org/torspec.git/tree/rend-spec-v3.txt#n615

[TODO: Also specify stealth client authorization.] (NOTE: client authorization is not implemented as of 0.3.2.1-alpha.)

Trac:
Keywords: client-authorization stealth-authorization, term-project 035-removed deleted, term-project, hs-auth, stealth-authorization, 035-removed, client-authorization added

hi, as a hsdir for a client, i can watch onion address request? but if unique onion address for each authorized client exists, i know it is the same client again. since no other would request it :( ? or do i misunderstood the spec