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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.




  • 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?



  • 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!





  • Circular dependencies can be removed in almost every case by splitting out a large module into smaller ones and adding an interface or two.

    In your bot example, you have a circular dependency where (for example) the bot needs to read messages, then run a command from a module, which then needs to send messages back.

        v-----------\
      bot    command_foo
        \-----------^
    

    This can be solved by making a command conform to an interface, and shifting the responsibility of registering commands to the code that creates the bot instance.

        main <---
        ^        \
        |          \
        bot ---> command_foo
    

    The bot module would expose the Bot class and a Command instance. The command_foo module would import Bot and export a class implementing Command.

    The main function would import Bot and CommandFoo, and create an instance of the bot with CommandFoo registered:

    // bot module
    export interface Command {
        onRegister(bot: Bot, command: string);
        onCommand(user: User, message: string);
    }
    
    // command_foo module
    import {Bot, Command} from "bot";
    export class CommandFoo implements Command {
        private bot: Bot;
    
        onRegister(bot: Bot, command: string) {
            this.bot = bot;
        }
    
        onCommand(user: User, message: string) {
            this.bot.replyTo(user, "Bar.");
        }
    }
    
    // main
    import {Bot} from "bot";
    import {CommandFoo} from "command_foo";
    
    let bot = new Bot();
    bot.registerCommand("/foo", new CommandFoo());
    bot.start();
    

    It’s a few more lines of code, but it has no circular dependencies, reduced coupling, and more flexibility. It’s easier to write unit tests for, and users are free to extend it with whatever commands they want, without needing to modify the bot module to add them.


  • eth0p@iusearchlinux.fyitoAsklemmy@lemmy.ml*Permanently Deleted*
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    1 year ago

    A couple years back, I had some fun proof-of-concepting the terrible UX of preventing password managers or pasting passwords.

    It can get so much worse than just an alert() when right-clicking.

    The codepen.

    A small note: It doesn’t work with mobile virtual keyboards, since they don’t send keystrokes. Maybe that’s a bug, or maybe it’s a security feature ;)

    But yeah, best tried with a laptop or desktop computer.

    How it detects password managers:

    • Unexpected CSS or DOM changes to the input element, such as an icon overlay for LastPass.

    • Paste event listening.

    • Right clicking.

    • Detecting if more than one character is inserted or deleted at a time.

    In hindsight, it could be even worse by using Object.defineProperty to check if the value property is manipulated or if setAttribute is called with the value attribute.


  • This may be an unpopular opinion, but I like some of the ideas behind functional programming.

    An excellent example would be where you have a stream of data that you need to process. With streams, filters, maps, and (to a lesser extent) reduction functions, you’re encouraged to write maintainable code. As long as everything isn’t horribly coupled and lambdas are replaced with named functions, you end up with a nicely readable pipeline that describes what happens at each stage. Having a bunch of smaller functions is great for unit testing, too!

    But in Java… yeah, no. Java, the JVM and Java bytecode is not optimized for that style of programming.

    As far as the language itself goes, the lack of suffix functions hurts readability. If we have code to do some specific, common operation over streams, we’re stuck with nesting. For instance,

    var result = sortAndSumEveryNthValue(2, 
                     data.stream()
                         .map(parseData)
                         .filter(ParsedData::isValid)
                         .map(ParsedData::getValue)
                    )
                    .map(value -> value / 2)
                    ...
    

    That would be much easier to read at a glance if we had a pipeline operator or something like Kotlin extension functions.

    var result = data.stream()
                    .map(parseData)
                    .filter(ParsedData::isValid)
                    .map(ParsedData::getValue)
                    .sortAndSumEveryNthValue(2) // suffix form
                    .map(value -> value / 2)
                    ...
    

    Even JavaScript added a pipeline operator to solve this kind of nesting problem.

    And then we have the issues caused by the implementation of the language. Everything except primitives are an object, and only objects can be passed into generic functions.

    Lambda functions? Short-lived instances of anonymous classes that implement some interface.

    Generics over a primitive type (e.g. HashMap<Integer, String>)? Short-lived boxed primitives that automatically desugar to the primitive type.

    If I wanted my functional code to be as fast as writing everything in an imperative style, I would have to trust that the JIT performs appropriate optimizations. Unfortunately, I don’t. There’s a lot that needs to be optimized:

    • Inlining lambdas and small functions.
    • Recognizing boxed primitives and replacing them with raw primitives.
    • Escape analysis and avoiding heap memory allocations for temporary objects.
    • Avoiding unnecessary copying by constructing object fields in-place.
    • Converting the stream to a loop.

    I’m sure some of those are implemented, but as far as benchmarks have shown, Streams are still slower in Java 17. That’s not to say that Java’s functional programming APIs should be avoided at all costs—that’s premature optimization. But in hot loops or places where performance is critical, they are not the optimal choice.

    Outside of Java but still within the JVM ecosystem, Kotlin actually has the capability to inline functions passed to higher-order functions at compile time.

    /rant


  • Yep! I ended up doing my entire co-op with them, and it meshed really well with my interest in creating developer-focused tooling and automation.

    Unfortunately I didn’t have the time to make the necessary changes and get approval from legal to open-source it, but I spent a good few months creating a tool for validating constraints for deployments on a Kubernetes cluster. It basically lets the operations team specify rules to check deployments for footguns that affect the cluster health, and then can be run by the dev-ops teams locally or as a Kubernetes operator (a daemon service running on the cluster) that will spam a Slack channel if a team deploys something super dangerous.

    The neat part was that the constraint checking logic was extremely powerful, completely customizable, versioned, and used a declarative policy language instead of a scripting language. None of the rules were hard-coded into the binary, and teams could even write their own rules to help them avoid past deployment issues. It handled iterating over arbitrary-sized lists, and even could access values across different files in the deployment to check complex constraints like some value in one manifest didn’t exceed a value declared in some other manifest.

    I’m not sure if a new tool has come along to fill the niche that mine did, but at the time, the others all had their own issues that failed to meet the needs I was trying to satisfy (e.g. hard-coded, used JavaScript, couldn’t handle loops, couldn’t check across file boundaries, etc.).

    It’s probably one of the tools I’m most proud of, honestly. I just wish I wrote the code better. Did not have much experience with Go at the time, and I really could have done a better job structuring the packages to have fewer layers of nested dependencies.