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Re:Apple cracking down on 'fingerprinting' with new App Stor... by eropple on Friday July 28, 2023 @12:12PM (#36909059)
As I have said elsewhere, this is the compromise position. The extreme position is "there is no option for pasteboard access at all and all pasteboard interactions must happen through OS-provided, fully disintermediated controls."

You already have a compromise: you can, if you insist and if your user consents--not Apple through some "trusted certificate" granting process but the user themselves--choose to not follow standard system flows. Or you can follow standard system flows and receive implicit consent by the user when they click 'Copy' in the share sheet.

Why is seeking consent so terrifying a prospect? And why should anyone privilege "your flows" over that consent?

Re:Apple cracking down on 'fingerprinting' with new App Stor... by asow92 on Friday July 28, 2023 @12:39PM (#36909522)
I don't have a problem with seeking consent from the user, and that's exactly what Firebase Dynamic Links offered by including "Check to continue my place in the app" on by default, but that product is no more thanks to Apple. Consent is given on the webpage before going to the App Store.

My issue is with Apple acting as the arbiters of what consent looks like. You have to consent with the flow to go through with it, right? Nobody's forcing our users to continue.

And like I have already said, it's not like we can't do what you're suggesting. In fact, we have, but that it equates to more churn in our flows because users get confused or are fatigued by the amount of hoops they have to jump through to make the product work, which was my original point to this whole thread.

Re:Apple cracking down on 'fingerprinting' with new App Stor... by eropple on Friday July 28, 2023 @01:26PM (#36910231)
Ground truth, inviolate: the OS owns the trust relationship with the user. The OS may allow the extension of that trust relationship (MDM, custom TLS roots, etc.) but that's informing the OS's own authorization, it's not supplanting it. It follows, then, Apple is the arbiter of consent on an iOS device because they own the OS (the user has chosen to, by buying an iOS device, grant the authorizee's part of the trust relationship).

Apple does not have a trusted relationship with you, the software developer. And Apple doesn't know about a trust relationship between the user and the software developer until the OS sees confirmation from the user.

It then follows that consent must be given at or inside the security boundary to be provable; the web page you refer to is outside of it. You are asking to move from a less trusted environment (a web browser, generally watched like a hawk) to a more trusted environment (an application, with additional implicit permissions and the explicit ability to ask for others). That isn't a decision you are allowed to make and it isn't something that, for all Apple knows, you confused-deputy'd your way around a user's affirmatively consenting to.

It's turtles all the way down. You have to acquire consent at a trustable level. That means the OS or, if the OS isn't sure, the user themselves, through an OS-verifiable method. Sorry that your third-party vendor doesn't count, but it shouldn't. "Just trust me" isn't security.

"But nobody cares" might be next up, so let's settle that now: nobody cares because they pay Apple to care for them.

Re:Apple cracking down on 'fingerprinting' with new App Stor... by asow92 on Friday July 28, 2023 @01:56PM (#36910656)
> Apple does not have a trusted relationship with you, the software developer.

Yeah, they do, because they have to trust the certificates and entitlements that my app is signed with. All I'm asking for is an extension of that same idea to other parts of the app experience.

I just don't think we're going to agree on this, and that's fine. Care to call it a day and we can respectfully both walk away?

Re:Apple cracking down on 'fingerprinting' with new App Stor... by Kamq on Friday July 28, 2023 @10:01PM (#36916045)
> Yeah, they do, because they have to trust the certificates and entitlements that my app is signed with.

That's a 401 vs 403 distinction. They know who you are, they don't know that you're authorized to do this.

Re:Apple cracking down on 'fingerprinting' with new App Stor... by asow92 on Friday July 28, 2023 @10:55PM (#36916366)
I get what you’re saying but have to disagree because it’s kind of different. Apple has to review our apps before they’re released and they certainly have capability to review a trusted pasteboard copying predicate as I am suggesting. They are would have the authority to revoke it at any time and I would certainly not want to risk my developer account being put into jeopardy by breaking their trust.
Re:Apple cracking down on 'fingerprinting' with new App Stor... by Kamq on Saturday July 29, 2023 @12:05AM (#36916785)
> Apple has to review our apps before they’re released and they certainly have capability to review a trusted pasteboard copying predicate as I am suggesting.

Are you willing to provide signed proof that the user consented to this action? The same way you provide signed code to prove you're the one uploading the code. Presumably this would have to be via a key that you don't have access to (only the user would be able to consent to this).

Because that seems like the parallel here.

Technically, apple should be auditing your flows at that point too, to make sure there aren't any dark patterns.

But, yeah, at that point, I think you could make that argument stick.

Re:Apple cracking down on 'fingerprinting' with new App Stor... by asow92 on Saturday July 29, 2023 @08:29AM (#36919622)
If we can do it in a way that reduces friction and doesn’t break the flow, then absolutely yes.
Re:Apple cracking down on 'fingerprinting' with new App Stor... by philposting on Saturday July 29, 2023 @09:38AM (#36920191)
Speaking from a user point of view, I find arguments like this are often disingenuous (I'm not saying that yours is). "Tailoring for the user" normally actually means "tracking the user". Specifically, the passing of UTM parameters from my website session to my app session is something that normally has no benefit to me and I find it repugnant that developers feel entitled to do it.
Re:Apple cracking down on 'fingerprinting' with new App Stor... by eropple on Sunday July 30, 2023 @08:49PM (#36937694)
> they certainly have capability to review a trusted pasteboard copying predicate as I am suggesting

They do not have the capability to exhaustively check all uses thereof in a way that obviates the need for a user to consent to having you monitor their pasteboard.

They could develop it, expending significant resources on an edge-case for a tiny fraction of app developers, or they could ask the user for permission because the user has the context to expect this request (or to not).

Re:Apple cracking down on 'fingerprinting' with new App Stor... by asow92 on Sunday August 06, 2023 @05:28PM (#37026996)
They already do similar stuff like cross referencing applinks at .well-know/apple-app-site-association with the associated domains bundled in your binary.

What I'm suggesting is a predicate like only allow NSPasteboard access without prompting iff the predicate passes something like let predicate = NSPredicate(format: "SELF MATCHES %@", "^/.\\?var=.$")

I don't think you know what you're talking about.