Allow some Moat DomainFrontedRequests to be cancelled

Merge Info

Issues

Resolves

• #43254 (closed)

Related

Merging

Target Branches

• tor-browser - !fixups to tor-browser-specific commits, new features, security backports
• base-browser and mullvad-browser - !fixups to base-browser-specific commits, new features to be shared with mullvad-browser, and security backports
  • ⚠️ IMPORTANT: Please list the base-browser-specific commits which need to be cherry-picked to the base-browser and mullvad-browser branches here

Target Channels

• Alpha: esr128-14.5
• Stable: esr128-14.0
• Legacy: esr115-13.5

Backporting

Timeline

• No Backport (preferred): patchset for the next major stable
• Immediate: patchset needed as soon as possible (fixes CVEs, 0-days, etc)
• Next Minor Stable Release: patchset that needs to be verified in nightly before backport
• Eventually: patchset that needs to be verified in alpha before backport

(Optional) Justification

• Security update: patchset contains a security fix (be sure to select the correct item in Timeline)
• Censorship event: patchset enables censorship circumvention
• Critical bug-fix: patchset fixes a bug in core-functionality
• Consistency: patchset which would make development easier if it were in both the alpha and release branches; developer tools, build system changes, etc
• Sponsor required: patchset required for sponsor
• Localization: typos and other localization changes that should be also in the release branch
• Other: please explain

Issue Tracking

• Link resolved issues with appropriate Release Prep issue for changelog generation

Review

Request Reviewer

• Request review from an applications developer depending on modified system:
  • NOTE: if the MR modifies multiple areas, please /cc all the relevant reviewers (since Gitlab only allows 1 reviewer)
  • accessibility : henry
  • android : clairehurst, dan
  • build system : boklm
  • extensions : ma1
  • firefox internals (XUL/JS/XPCOM) : jwilde, ma1
  • fonts : pierov
  • frontend (implementation) : henry
  • frontend (review) : donuts, morgan
  • localization : henry, pierov
  • macOS : clairehurst, dan
  • nightly builds : boklm
  • rebases/release-prep : dan, ma1, pierov, morgan
  • security : jwilde, ma1
  • signing : boklm, morgan
  • updater : pierov
  • windows : jwilde, morgan
  • misc/other : pierov, morgan

Change Description

We add an option to DomainFrontedRequests to pass in an AbortSignal to be able to cancel the request's channel.

This is also exposed in some of the MoatRPC API as well. Specifically:

1. We cancel BridgeDB fetches and solutions if the bridge dialog is closed early.
2. We cancel circumvention_settings calls when an "AutoBootstrap" is cancelled.

I did not bother with cancelling the internet test since it is due to be removed in another issue.

As part of the changes to MoatRPC.check, I dropped the unused qrcode argument and return value.

How Tested

Set the browser.torMoat.loglevel to All.

Set torbrowser.debug.censorship_level to 1. Quickly clicking "Cancel" after "Try bridges" will cancel the Moat request, depending on the timing.

Open the "Request bridges" dialog and immediately close with Escape key. Similarly close the dialog just after submitting the solution.

Both of these still work when not cancelled.