There's nothing guaranteeing that Deb contains the same thing as source Deb. At the end of the day you still need to trust the organization building your OS so they don't push a backdoor in your root installed package.

> There's nothing guaranteeing that Deb contains the same thing as source Deb.

That's blatantly understating how many packages are reproducible.

No it's not - reproducibility doesn't defend you against malicious repository at all. You still need to trust every single maintainer of your packages and the repository owner to not serve you backdoored package.

Yes and no. Just having reproducibility does not automatically prevent bad things from happening. But it's certainly easier to defend against them.

Multiple people can grab the sources from the developer, review and apply the patches, build the package and publish the resulting hash. With reproducible builds, all people end up with the same hash, which should also be the same for the pre-built package in the repository.

In other words, instead of trusting one single person (the maintainer) you split the trust across multiple people. This is definitely an improvement thanks to reproducible builds.

This is what reproducible builds try to fix: https://wiki.debian.org/ReproducibleBuilds

> At the end of the day you still need to trust the organization building your OS so they don't push a backdoor in your root installed package.

I am curious what are good solutions to this problem? Compile your OS (and any other software) from source?

Somewhere a Gentoo maintainer's ears are ringing, but they don't know why...

A backdoor/bugdoor is much more likely to be in the source code. Compiling the code by yourself does not help.

You have to rely on a distribution that has a many-eyes review policy and has security conscious users.

Isn't this exactly why they're doing the reproducible build stuff?

No, you can already download the source .debs, rebuild them and compare the results.

And, there are large tech firms doing this already.

You can do the same thing here. There is no hard requirement that you use Google Play. If the app developers publish their source you can build an apk yourself.

Most apps on Google Play are proprietary and cannot be rebuilt.

That is the developer's fault, surely.

No, it's the developer's _choice_. The problem is that there are instances where you trust the developer but not the way it is distributed (commonly through Google's app store). I signature from the developer is enough to verify that the app has not been tempered with.

With the upcoming change, we loose this verification when using Google's app store.

This has nothing to do with the developer publishing the source and allowing you to build from source or publishing through other channels (the topic of this subthread).

Developers can still create key pairs themselves and upload them to Google. So they can still publish their public key if they want and you can be certain that APKs distributed from somewhere other than Play were definitely signed by the developer.