1640135 - Consider using separate attribute to store first-party domain for dFPI

Status: RESOLVED FIXED

(Core :: Privacy: Anti-Tracking, enhancement, P1)

Description

[Gary Chen [:xeonchen]]

mFirstPartyDomain was introduced by first-party isolation (FPI), and dynamic first-party isolation (dFPI) reuses this attribute. This may be problematic especially when both mode are enabled (see bug 1631676).

Adding another attribute for dFPI seems reasonable and is quite cheap, we should probably consider doing this.

Comment 1

[Anne (:annevk)]

I think we already settled that FPI and dFPI should be mutually exclusive, right? I.e., if you enable one, the other is disabled.

Then in bug 1637516 we'd like to move the keying from top-level registrable domain to site. If we did that on top of mFirstPartyDomain it would contain a different value based on which of FPI or dFPI is enabled. That probably works, but starts getting confusing. (Migrating FPI to site is being considered as well, but is much more complicated as it already shipped.)

Also, dFPI will be impacted by follow-up projects to Fission eventually where there is a desire to hide values from processes the process would not otherwise have access to, i.e., the top-level site (when its referrer policy is "no-referrer"). We don't have to tackle that now, but that would also impact this key and not having it impact FPI in addition would probably make that easier.

Then in discussions we've considered adding even more keying for non-storage state, though that would likely require another attribute whichever way we go.

Comment 2

[Gary Chen [:xeonchen]]

Attachment: Bug 1640135 - P1: add new attribute for dFPI;

Comment 3

[Gary Chen [:xeonchen]]

Attachment: Bug 1640135 - P2: add new setter;

Depends on D77914

Comment 4

[Gary Chen [:xeonchen]]

Attachment: Bug 1640135 - P3: implement new setter;

Depends on D77915

Comment 5

[Gary Chen [:xeonchen]]

Attachment: Bug 1640135 - P4: update usage of PartitionKey;

Depends on D77916

Comment 6

[Gary Chen [:xeonchen]]

Attachment: Bug 1640135 - P5: update tests;

Depends on D77917

Comment 7

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/42f2bdd06a95
P1: add new attribute for dFPI; r=timhuang
https://hg.mozilla.org/integration/autoland/rev/9a58e5805c83
P2: add new setter; r=timhuang
https://hg.mozilla.org/integration/autoland/rev/bd311336daa7
P3: implement new setter; r=timhuang
https://hg.mozilla.org/integration/autoland/rev/64399b8f0d7c
P4: update usage of PartitionKey; r=timhuang
https://hg.mozilla.org/integration/autoland/rev/f318f0c9b8f3
P5: update tests; r=timhuang

Comment 8

[Andreea Pavel [:apavel]]

https://hg.mozilla.org/mozilla-central/rev/42f2bdd06a95
https://hg.mozilla.org/mozilla-central/rev/9a58e5805c83
https://hg.mozilla.org/mozilla-central/rev/bd311336daa7
https://hg.mozilla.org/mozilla-central/rev/64399b8f0d7c
https://hg.mozilla.org/mozilla-central/rev/f318f0c9b8f3