The firejail URL open game: Level fireurl unlocked

[rusty-snake]

Level 0: Nothing is working. URLs do not open.
Level 1: Allow firefox to start and IPC to a running instance to open the URL.
Level 2: firejail-handler-http (unlocked by @glitsj16, Jul 2020)
Level 3: xdg-open.c (unlocked by @rusty-snake, Mar 2021)
Level 4: fireurl (unlocked by @rusty-snake, Sep 2022)
Level 5: 〰〰〰〰〰〰 (unlocked by @〰〰, 〰 〰〰)

Relates to:

• [meta] Opening links outside of the sandbox #6462

[glitsj16]

Interesting and much needed topic.

Just so it is clear from the outset, what would be our preferred goal here? I mean, are we going for a non-D-Bus solution, a (limited) D-Bus filtering solution or whatever integrates easiest into the current code-base? Looking forward to the discussion!

[rusty-snake]

We should also consider use cases like #3785 to be implemented on top of this in the future.

[glitsj16]

I would prefer a non-D-Bus solution if possible. Besides the security win it would keep profile maintenance to a minimum.

[rusty-snake]

If we use D-Bus, it have to be transparent to profiles (maybe an opt out).

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Anyway, I think that an own private socket per sandbox is a way to follow. It would allow to identify the source of an request and therefore it is possible to implement complexer features on top of it that need per sandbox filtering.

[topimiettinen]

Some kind of access control and path sanitization would be nice.

[glitsj16]

For reference, this turned up again in #5566. There's also firefox-socket. I have been using that before I even knew there was fireurl.

So all in all there are good options out there as to how to fix this. IMO the question we need to focus on is when are we going to do this in Firejail and who is the 'we'?