Archlinux Pacman GPG

So I'm not impressed that Archlinux has gone down the GPG route.

It's no secret, I don't like GPG and I long for a lightweight solution. However engaging in a security debate with "security experts" always seems to get heated. Armed with an asbestos suit and repeated calls for me to "Go take a security course", lets try understand this nonsense.

If you update Archlinux, GPG signing is turned on default. You need to:

sudo cp /etc/pacman.conf.pacnew /etc/pacman.conf

Copy in the "default config" to disable it. A little confusing, I know.

GPG stinks

Firstly GPG based package signing and verification is complex.

Secondly I don't like the whole Web of trust bullshit. Do I want to trust Eric Belanger? Do I want to attend GPG signing parties to establish some sort of link to Eric? NO

I want to trust the team behind Archlinux ideally. An Archlinux security team, that somehow look out for integrity issues in packages.

I do not want to trust individuals and therefore trust their individual handling of their private keys.

Individuals rarely follow good key practices like rotating their keys. Revocation is a PITA. What happens if a compromised package gets uploaded? People focus on all these GPG key procedures, but what the FUCK happens when a rootkit is installed on a machine?

falconindy argues that lots of people having private keys distributes risk. That compromising one key doesn't compromise everything. In my binary world, either the machine is compromised or it isn't. Having >5 individuals with private keys and the ability to upload rootkit packages increases the attack surface area.

It's HARD to maintain one's own private (ssh) key in a safe manner. Oh no, you can't have it on a server. Oh, but can you leave your private laptop un-attended? So WHAT if it has a password protecting it?

Sucky GPG procedures raises the barrier to entry for core developers. Now you don't just need to be good at packaging, you have to learn the whole key handling rigmarole. PAIN.

What's the alternative solution?

Whilst criticizing GPG, a common retort is ask me what my alternative solution is on the spot. That's not the point. The point here is GPG stinks.

So, Archlinux probably needs a way of securely verifying the integrity of packages.

I've informally proposed using the secure transport of HTTPS to distribute hashes (which I don't think is that server straining) to simply see if something has gone awry. This is criticized as it gives one massive failure point on the server. Is someone manages to manipulate the hashes or rather sneaks in a rooted package at the server, you are fucked. But, I'd rather have one castle. At least it (HTTPS) protects man in the middle attack and one disciplined team proactively maintaining security is simple and accountable.

I asked what would happen if a compromised GPG upload took place and I had the reply:

04:37 <falconindy> hendry: _if_ a key is compromised, the attacker still needs
to get a package built and onto the servers, which requires getting through
more layer of security. ideally in that time period, its revoked and we have a
new key in place

Reading the Archlinux news item & package signing wiki, I'm still struggling to understand how these "layers" work.

I'm all for layers, in the sense PKGBUILDs are reviewed again and again, like the AUR, but I fear falconindy just says "layers" as a deflecting that a serious compromise can happen after a developer's GPG key is compromised.

I fear people will think, "oh it has a valid signature, it must be safe" and it corrupts preventative review culture. GPG sets up such obstacles, that even if you found a problem, only the signer can apply the patch. Debian style stagnation results.

Please convince me otherwise security folks. Please avoid the adhominem attacks and lets have a sensible debate. :)

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