Web Inspector: WebKit-internal JSContexts should not be inspectable, even if internal policies would override inspectable

[patrickangle]

11aafb6

Web Inspector: WebKit-internal JSContexts should not be inspectable, even if internal policies would override `inspectable`
https://bugs.webkit.org/show_bug.cgi?id=250633
rdar://103312497

Reviewed by Saam Barati.

On configurations where `inspectable` can be overriden, there are still some WebKit-internal contexts that should not be
inspectable. The first are JSDOMGlobalObjects, which are already inspectable via the WKWebView they exist for by using
the context picker in Web Inspector, making these JSContexts redundant and noisy. The second case is
APISerializedScriptValueCocoa which creates JSContexts to help serialize values to/from JS/Cocoa.

This problem did not exist before the introduction of the `inspectable` API because the default state of `inspectable`
was false, which would not be overriden because the decision by the platform as to whether an application was inspectable
occurred in a system daemon, which would not override the per-context `inspectable` setting. When unifying the decision
logic for what is inspectable into JSC/WebKit, this use case was initially overlooked as the only platform that implements
an internal policy for inspection doesn't have any symptoms of this that a user could observe due to the specific policy.
However, in use for those working on machines where this policy is applied, the noise of so many JSContexts is making it
difficult to sort through usefully inspectable contexts in Safari's Develop menu.

This patch also fixes a minor bug where `inspectable` would return `true` for JSContexts and WKWebViews, even if
inspection was disabled, when an internal policy is overriding inspection.

* Source/JavaScriptCore/API/JSRemoteInspector.cpp:
(JSRemoteInspectorGetInspectionFollowsInternalPolicies):
(JSRemoteInspectorSetInspectionFollowsInternalPolicies):
* Source/JavaScriptCore/API/JSRemoteInspector.h:
- Add methods to set and get the new "followsInternalPolicies" state to be applied to new contexts as well as those that
change their `inspectable` setting.

* Source/JavaScriptCore/inspector/JSGlobalObjectInspectorController.cpp:
(Inspector::JSGlobalObjectInspectorController::developerExtrasEnabled const):
* Source/JavaScriptCore/inspector/remote/cocoa/RemoteInspectorCocoa.mm:
(Inspector::RemoteInspector::listingForInspectionTarget const):
* Source/JavaScriptCore/inspector/remote/glib/RemoteInspectorGlib.cpp:
(Inspector::RemoteInspector::listingForInspectionTarget const):
* Source/JavaScriptCore/inspector/remote/socket/RemoteInspectorSocket.cpp:
(Inspector::RemoteInspector::listingForInspectionTarget const):
- Use new `allowsInspectionByPolicy` which takes into account internal policies.

* Source/JavaScriptCore/inspector/remote/RemoteInspectionTarget.cpp:
(Inspector::RemoteInspectionTarget::remoteControlAllowed const):
(Inspector::RemoteInspectionTarget::allowsInspectionByPolicy const):
(Inspector::RemoteInspectionTarget::inspectable const):
(Inspector::RemoteInspectionTarget::setInspectable):
(Inspector::RemoteInspectionTarget::pauseWaitingForAutomaticInspection):
* Source/JavaScriptCore/inspector/remote/RemoteInspectionTarget.h:
- Use the new `followsInternalPolicies` state to keep track of when a target should be exempt from internal policies for
contexts that never make sense to be inspectable.
- Introduce `allowsInspectionByPolicy` which takes into account internal policy when determining the inspectability of
a target. Previously this was baked into `inspectable`, but that inadvertently leaks the internal policy implementation
detail to clients of JSContext and WKWebView.

* Source/WebCore/bindings/js/JSDOMGlobalObject.cpp:
(WebCore::JSDOMGlobalObject::finishCreation):
* Source/WebKit/UIProcess/API/Cocoa/APISerializedScriptValueCocoa.mm:
(API::SharedJSContext::ensureContext):
- Adopt new methods to mark the contexts created here as never inspectable since they do not expose any useful information.

Canonical link: https://commits.webkit.org/259000@main

c78b5ff

Misc	iOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 🧪 win
✅ 🧪 bindings	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	✅ 🛠 gtk	✅ 🛠 wincairo
✅ 🧪 webkitperl	✅ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🧪 gtk-wk2
	✅ 🧪 api-ios	✅ 🧪 mac-wk1	✅ 🧪 api-gtk
✅ 🛠 🧪 jsc	✅ 🛠 tv	✅ 🧪 mac-wk2	✅ 🛠 jsc-armv7
✅ 🛠 🧪 jsc-arm64	✅ 🛠 tv-sim	✅ 🧪 mac-AS-debug-wk2	✅ 🧪 jsc-armv7-tests
	✅ 🛠 watch	✅ 🧪 mac-wk2-stress	✅ 🛠 jsc-mips
❌ 🛠 🧪 merge	✅ 🛠 watch-sim		✅ 🧪 jsc-mips-tests

[webkit-early-warning-system]

EWS run on previous version of this PR (hash 98d8881)

Misc	iOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	❌ 🛠 🧪 win
✅ 🧪 bindings	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	✅ 🛠 gtk	🛠 wincairo
✅ 🧪 webkitperl	✅ 🧪 ios-wk2	⏳ 🧪 api-mac	🧪 gtk-wk2
	✅ 🧪 api-ios	✅ 🧪 mac-wk1	✅ 🧪 api-gtk
✅ 🛠 🧪 jsc	✅ 🛠 tv	✅ 🧪 mac-wk2	✅ 🛠 jsc-armv7
✅ 🛠 🧪 jsc-arm64	✅ 🛠 tv-sim	✅ 🧪 mac-AS-debug-wk2	✅ 🧪 jsc-armv7-tests
	✅ 🛠 watch	✅ 🧪 mac-wk2-stress	✅ 🛠 jsc-mips
	✅ 🛠 watch-sim		✅ 🧪 jsc-mips-tests

[webkit-early-warning-system]

EWS run on current version of this PR (hash 4468221)

Misc	iOS, tvOS & watchOS	macOS	Linux	Windows
🧪 style	⏳ 🛠 ios	⏳ 🛠 mac	🛠 wpe	🛠 🧪 win
⏳ 🧪 bindings	⏳ 🛠 ios-sim	⏳ 🛠 mac-AS-debug	⏳ 🛠 gtk	⏳ 🛠 wincairo
⏳ 🧪 webkitperl	⏳ 🧪 ios-wk2	⏳ 🧪 api-mac	⏳ 🧪 gtk-wk2
🧪 webkitpy	⏳ 🧪 api-ios	⏳ 🧪 mac-wk1	⏳ 🧪 api-gtk
⏳ 🛠 🧪 jsc	⏳ 🛠 tv	⏳ 🧪 mac-wk2	⏳ 🛠 jsc-armv7
⏳ 🛠 🧪 jsc-arm64	⏳ 🛠 tv-sim	⏳ 🧪 mac-AS-debug-wk2	⏳ 🧪 jsc-armv7-tests
🧪 services	⏳ 🛠 watch	⏳ 🧪 mac-wk2-stress	⏳ 🛠 jsc-mips
	⏳ 🛠 watch-sim		⏳ 🧪 jsc-mips-tests

[webkit-early-warning-system]

EWS run on previous version of this PR (hash 4468221)

Misc	iOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 🧪 win
✅ 🧪 bindings	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	✅ 🛠 gtk	✅ 🛠 wincairo
✅ 🧪 webkitperl	✅ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🧪 gtk-wk2
	✅ 🧪 api-ios	✅ 🧪 mac-wk1	✅ 🧪 api-gtk
✅ 🛠 🧪 jsc	✅ 🛠 tv	❌ 🧪 mac-wk2	✅ 🛠 jsc-armv7
✅ 🛠 🧪 jsc-arm64	✅ 🛠 tv-sim	✅ 🧪 mac-AS-debug-wk2	✅ 🧪 jsc-armv7-tests
	✅ 🛠 watch	✅ 🧪 mac-wk2-stress	✅ 🛠 jsc-mips
	✅ 🛠 watch-sim		✅ 🧪 jsc-mips-tests

[saambarati]

Should the code in this switch case be done inside of setInspectable? That way, maybe we don't need this new enum with three values, and can keep using a bool?

[patrickangle]

Thank you for the feedback! Halfway through responding to this suggestion I realized we have a bug that will likely require us to do this work in the getter.

There is actually a bug here currently that occurs when internal policies are being applied: the APIs for WKWebView and JSContext will return true even for contexts that have disabled inspection at the API level, meaning the setting of inspectable on those objects won't appear to do anything on system following an internal policy, which could lead to confusing or undesirable behavior in applications. The internal policies are meant to be invisible to clients of the libraries, but currently we are technically leaking this implementation detail.

Really what we should have is an inspectable getter like we have today that ignores internal policies, and an extra allowsInspection that actually takes internal policy into account, and is used by RemoteInspector* to determine the actual inspectability of the RemoteInspectionTarget.

For what its worth, the existing bool couldn't have been packed with any other bits anyway in this class, so the size of RemoteInspectionTarget should remain the same moving from bool to a uint8_t enum.

[saambarati]

I wonder if it's a better name is without the double negative. Maybe "inspectionFollowsInternalPolicies"? And it defaults to true.

[patrickangle]

That's a much better name for this, yes!

[webkit-early-warning-system]

EWS run on current version of this PR (hash c78b5ff)

Misc	iOS, tvOS & watchOS	macOS	Linux	Windows
✅ 🧪 style	✅ 🛠 ios	✅ 🛠 mac	✅ 🛠 wpe	✅ 🛠 🧪 win
✅ 🧪 bindings	✅ 🛠 ios-sim	✅ 🛠 mac-AS-debug	✅ 🛠 gtk	✅ 🛠 wincairo
✅ 🧪 webkitperl	✅ 🧪 ios-wk2	✅ 🧪 api-mac	✅ 🧪 gtk-wk2
	✅ 🧪 api-ios	✅ 🧪 mac-wk1	✅ 🧪 api-gtk
✅ 🛠 🧪 jsc	✅ 🛠 tv	✅ 🧪 mac-wk2	✅ 🛠 jsc-armv7
✅ 🛠 🧪 jsc-arm64	✅ 🛠 tv-sim	✅ 🧪 mac-AS-debug-wk2	✅ 🧪 jsc-armv7-tests
	✅ 🛠 watch	✅ 🧪 mac-wk2-stress	✅ 🛠 jsc-mips
❌ 🛠 🧪 merge	✅ 🛠 watch-sim		✅ 🧪 jsc-mips-tests

[webkit-commit-queue]

Committed 259000@main (11aafb6): https://commits.webkit.org/259000@main

Reviewed commits have been landed. Closing PR #8666 and removing active labels.