1825947 - [DNR] testMatchOutcome should account for restricted domains by not returning matches

Status: RESOLVED FIXED

(WebExtensions :: Request Handling, enhancement, P3)

Description

[Rob Wu [:robwu]]

The (debug helper) testMatchOutcome method does not account for restricted domains. Since this method is supposed to be used by extension authors for debugging purposes, it should account for restricted domains to be consistent with what had been implemented for actual DNR evaluations for the network, and to expand the unit tests at https://searchfox.org/mozilla-central/rev/e941c8a6d49b4f62f361446de7a80214fb899186/toolkit/components/extensions/test/xpcshell/test_ext_dnr_system_restrictions.js to verify that the results are similar.

The relevant check is at channel.canModify in ExtensionDNR.sys.mjs, whose implementation (ChannelWrapper::CanModify) rejects system loads and requests to restricted URLs. Since system requests cannot be simulated by testMatchOutcome, it suffices to only implement the restricted URL check for the request URL + "initiator" URL.

Comment 1

[Rob Wu [:robwu]]

Attachment: Bug 1825947 - Expand coverage of test_ext_dnr_system_restrictions.js

Test-only change to expand coverage:

• Rules without "resourceTypes" do not block main frames by default.
  This was desirable because otherwise we could not be simulating
  fetch() requests from specified origins.
  However, it also meant that we lacked test coverage that verified
  that we wouldn't be blocking the main frame.
  Now we have that: dnr_ignores_css_import_at_restrictedDomains.

• While I am at it, I also added extra test coverage for the case
  where the triggering principal is NOT a restricted domain. While
  the implementation works as desired, there was no explicit test
  case for this scenario.

Comment 2

[Rob Wu [:robwu]]

Attachment: Bug 1825947 - Exclude restricted domains from testMatchOutcome

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/86fbbf43e126
Expand coverage of test_ext_dnr_system_restrictions.js r=rpl
https://hg.mozilla.org/integration/autoland/rev/0110fc953165
Exclude restricted domains from testMatchOutcome r=rpl

Comment 4

[Norisz Fay [:noriszfay]]

https://hg.mozilla.org/mozilla-central/rev/86fbbf43e126
https://hg.mozilla.org/mozilla-central/rev/0110fc953165