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Joined 1 year ago
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Cake day: June 17th, 2023

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  • The image needs to have already been downloaded the moment the client even fetches it, or you can use the image to track of a particular user is online/has read the message.

    Oh wow… That’s an excellent point. And even if the client downloads it the moment it fetches the message, that would still be enough to help determine when somebody is using Lemmy. I don’t think advertisers would have a reason to do that1, but I wouldn’t put it past a malicious individual to use it to create a schedule of when somebody else is active.

    1 It’s probably easier for them to host their own instance and track the timestamp of when somebody likes/dislikes comments and posts since that data is shared through federation.

    This needs to be implemented in the backend. Images already get downloaded to and served from the server’s pictr-rs store in some instances, so there’s code to handle this problem already.

    That would be ideal, I agree. This comment on the GitHub issue explains why some instances would want the ability to disable it, though. If it does eventually get implemented, having Sync as a fallback for instances where media proxying is disabled would be a major benefit for us Sync users.

    A small side note: that comment also points out a risk of a media proxy running the risk of downloading illegal media. I don’t necessarily think lj would need to worry about it in the same way, though. From my understanding, the risk with that is that an instance would download the media immediately after receiving a local or federated post pointing it. An on-demand proxy would (hopefully) not run the same risk since it would require action (or really bad timing) on the part of a user.

    On the other hand, such a system would also pose a privacy problem: suppose someone foolishly believes Lemmy’s messaging feature is secure and sends a message with personal pictures (nudes, medical documents, whatever). Copying that data around to other servers probably isn’t what you want.

    Fair, but it’s a bit of a moot point. Sending the message between instances is already copying that data around, and even if it’s between two users of a single instance, it’s not end-to-end encrypted. Instance admins can see absolutely everything their users do.

    Orbot can do per-app VPNs for free if you’re willing to take the latency hit.

    Interesting! I wasn’t aware that there were any Android VPNs capable of doing per-app tunneling.



  • For spoofing the user agent, I still think that some level of obscurity could help. The IP address is the most important part, but when sharing an internet connection with multiple people, knowing which type/version of device would help disambiguate between people with that IP (for example, a house with an Android user and an iPhone user). I wouldn’t say not having the feature is a deal breaker, but I feel like any step towards making it harder to serve targeted ads is a good step.

    Fair point on just using a regular VPN, but I’m hoping for something a bit more granular. It’s not that all traffic would need to be proxied, though. If I use some specific Lemmy instance or click on an image/link, that was my choice to trust those websites. The concern here is that simply scrolling past an embedded image will make a request to some third-party website that I don’t trust.




  • I believe there’s a misunderstanding somewhere. I wasn’t suggesting anything; I was explaining how Web Environment Integrity could be altered in the future to kill extensions.

    The current form of WEI does not have the ability to enforce anything. It isn’t itself DRM, and it can’t prevent extensions from running on pages. What it can do and the only thing it does, is tell websites about the browser environment.

    Right now, the only thing it tells websites is the name of the browser. A website having the browser name can’t directly enforce page integrity. It’s already possible to find out the browser name through the user agent or by fingerprinting it with JavaScript.

    If WEI is approved and implemented, that opens up the possibility for future additions to the specification. Those changes could require that the browser sends more info to websites. I gave the example of a change that would require WEI tells the website that the browser has an extension which could modify the page contents.

    A website having that information would turn WEI into DRM. It gives the website the choice to refuse service to any browser that is running an extension that could change what the user sees.

    I hope that was more clear. I don’t expect Google to make changes that immediately block extensions, and then be kind enough to allow some of them back. I suspect they would make changes that don’t prevent extensions, and then revise them to prevent certain types of extensions.


  • In other posts, I’ve tried to point out how some of the articles and comments around WEI are more speculative than factual and received downvotes and accusations of boot-licking for it. Welcome to the club, I guess.

    The speculation isn’t baseless, but I’m concerned about the lack of accurate information about WEI in its current form. If the majority of people believe WEI is immediately capable of enforcing web page integrity, share that incorrect fact around, and incite others, it’s going to create a very good excuse for dismissing all dissenting feedback of WEI as FUD. The first post linking to the GitHub repository brought in so many pissed off/uninformed people that the authors of the proposal actually locked the repo issues, preventing anyone else from voicing their concerns or providing examples of how implementing the specification could have unintended or negative consequences.

    Furthermore, by highlighting the DRM and anti-adblock aspect of WEI, it’s failing to give proper attention to many of the other valid concerns like:

    • Discrimination against older hardware/software that doesn’t support system-level environment integrity enforcement (i.e. Secure Boot)
    • The ability for WEI to be used to discriminate between browsers and provide poor (or no) service to browsers not created by specific corporations.
    • The possibility of WEI being used in a way to force usage of browsers provided by hostile vendors
    • The ability for it to be used to lock out self-built browsers or forked browsers.
    • The potential for a lack in diversity of attesters allowing for a cartel of attesters to refuse validation for browsers they dislike.

    I very well could be wrong, but I think our (the public) opinions would have held more weight if they were presented in a rational, informed, and objective manner. Talking to software engineers as people generally goes down better than treating them like emotionless cogs in the corporate machine, you know?


  • I don’t disagree, and I’m personally aware of the consequences. Adding the API would be the first step, and future proposals and changes could amend it to add other environment details to tell a website that there are browser extensions that can read or modify the page.

    I don’t really think summarizing WEI as though it already includes those really helps people understand what WEI currently is or does, though. Nobody reads the actual documentation before repeating what they were told, and that’s going to lead to the spread of factually-incorrect information. It’s not a bad thing for people to be aware of the long-term issue with having a WEI API, but users’ lack of understanding of WEI in its current form is just going to be used by Google as proof to dismiss dissenting feedback as FUD.


  • To elaborate on why I’m saying a citation is needed: I read the entire proposal and specification myself, and I couldn’t find evidence affirming the statement.

    The Web Environment Integrity explainer document doesn’t require, suggest, or mention script or DOM integrity status under what information is in the signed attestation. Neither does the draft specification, which is pretty devoid of details. The closest it comes to that kind of thing is only enabling the API within a secure context, which basically means “the page was served over HTTPS using a valid certificate”.

    That doesn’t mean that WEI can’t be used to enforce page integrity in an extremely roundabout way1, but lacking a citation showing that it directly does that, it needs to be explained to people who are out of the loop how it can do that.

    1: One of the environment details sent to a website is a unique identifier for the browser. Blocking every browser except Android Chrome would limit the ability to use extensions to modify the website, since that browser doesn’t support them.




  • And here’s a concern about the decentralized-but-still-centralized nature of attesters:

    From my understanding, attesting is conceptually similar to how the SSL/TLS infrastructure currently works:

    • Each ultimately-trusted attester has their own key pair (e.g. root certificate) for signing.

    • Some non-profit group or corporation collects all the public keys of these attesters and bundles them together.

    • The requesting party (web browser for TLS, web server for WEI) checks the signature sent by the other party against public keys in the requesting party’s bundle. If it matches one of them, the other party is trusted. If it doesn’t, they are not not trusted.

    This works for TLS because we have a ton of root certificates, intermediate certificates, and signing authorities. If CA Foo is prejudice against you or your domain name, you can always go to another of the hundreds of CAs.

    For WEI, there isn’t such an infrastructure in place. It’s likely that we’ll have these attesters to start with:

    • Microsoft
    • Apple
    • Google

    But hey, maybe we’ll have some intermediate attesters as well:

    • Canonical
    • RedHat
    • Mozilla
    • Brave

    Even with that list, though, it doesn’t bode well for FOSS software. Who’s going to attest to various browser forks, or for browsers running on different operating systems that aren’t backed by corporations?

    Furthermore, if this is meant to verify the integrity of browser environments, what is that going to mean for devices that don’t support Secure Boot? Will they be considered unverified because the OS can’t ensure it wasn’t tampered with by the bootloader?


  • Adding another issue to the pile:

    Even if it isn’t the intent of the spec, it’s dangerous to allow for websites to differentiate between unverified browsers, browsers attested to by party A, and browser attested to by party B. Providing a mechanism for cryptographic verification opens the door for specific browsers to be enforced for websites.

    For a corporate example:

    Suppose we have ExampleTechFirm, a huge investor in a private AI company, ShutAI. ExampleTechFirm happens to also make a web browser, Sledge. ExampleTechFirm could exert influence on ShutAI so that ShutAI adds rate limiting to all browsers that aren’t verified with ShutAI as the attester. Now, anyone who isn’t using Sledge is being given a degraded experience. Because attesting uses cryptographic signatures, you can’t bypass this user-hostile quality of service mechanism; you have to install Sledge.

    For a political example:

    Consider that I’m General Aladeen, the leader of the country Wadiya. I want to spy on my citizens and know what all of them are doing on their computers. I don’t want to start a revolt by making it illegal to own a computer without my spyware EyeOfAladeen, nor do I have the resources to do that.

    Instead, I enact a law that makes it illegal for companies to operate in Wadiya unless their web services refuse access to Wadiyan citizens that aren’t using a browser attested to by the “free, non-profit” Wadiyan Web Agency. Next, I have my scientists create and release a renamed versions of Chromium and Firefox with EyeOfAladeen bundled in them. Those are the only two browsers that are attested by the Wadiyan Web Agency.

    Now, all my citizens are being encouraged to unknowingly install spyware. Goal achieved!