I agree that RedHat and Debian use OpenPGP mostly for its signature only and do not rely on any Web of Trust or other infrastructure for key distribution in the basic case. As a side-note just for fun:
They distribute their public keys on their own web infrastructure, so it's effectively TOFU. In your criticism of PyPI, you rightly pointed out that keys are useless unless pushed to a publicly-known key server because they aren't discoverable for users, which leads to ~no one verifying installs. I agree with this for PyPI, but in Postgres' case, if you do not have their key pulled locally, installs will fail by default. This means that users do generally install keys locally (actually they typically install the repo RPMs which configures local repositories as well as installs keys), even if the discovery mechanism isn't enforced by yum. My point here is that ecosystems without the ability to pre-bake rings of trust can still result in ~all downloads being verified as long as the client tooling defaults to the correct thing. pip not doing so is the main reason why OpenPGP signing never caught on in the Python ecosystem.
But yes, I agree: A modern day dpkg and rpm could swap to something with safer cryptography rather easily without changing anything about distribution. OpenPGP is a lot of bloat for their needs.
> Out of curiosity: which government standards? I'm not aware of a US Gov't standard that mandates PGP; this would be very valuable to know.
I don't believe any mandate OpenPGP specifically. I was more trying to get across that many institutions mandate FIPS 140-2/3, and current implementations (like on RHEL) complain if signatures are not present in their expected format. Because OpenPGP is my only choice for signing yum infrastructure and RPMs, it's a de-facto government standard today.
My guess is that there are a lot more "signature verification events" on Linux that pull from a deb or yum repository than there are on Windows servers, both because the mean server in terms of global usage seems to be Linux (though not the median, I'd think?) as well as because it seems like Linux folk rely an awful lot more on distribution repositories than Windows server users download things. Happy to be corrected if anyone has real numbers, though. My feelings are informed by my company's download statistics which may not be representative.
OK, fair point regarding bespoke PKI on Windows/Mac being more common. I do agree with that. I'll amend my statement to: PGP is by far the most common standard for server-side software distribution. I'll also quickly add that I agree that git signing is worthless as currently implemented.
I have read your blogpost and I agree that PyPI had unused and useless PGP support. I also agree that signatures are a waste of time when the client tooling does not verify by default. However, this is not true for the Linux distro packaging ecosystem where approximately all downloads have their signatures verified. Until you convince RedHat and Debian to move their packaging and repository formats to another standard, PGP will remain very relevant for production server software.
Don't mistake me as a defender of PGP-the-standard. I have absolutely no opinion on its cryptography. I would happily use minisign or any other tool that used only modern cryptography to produce signatures. As a distributor of software though, I don't really get to decide how to sign, I am at the mercy of government and ecosystem standards, and as a result no other signature scheme is close to the level of use that PGP has for enterprises that run server-side software.
Yes, it does matter. PGP is by far the most common standard for signatures used in software distribution (Git tags, RPM packages, Yum repos, Deb repos, ad-hoc signature schemes, etc.), and nothing else is particularly close in terms of number of signatures verified per day. While the absolute number of verifications is a lot lower than it could be, there is still substantial inertia behind these current standards, including US government standards.
I am also aware that you are actively involved in moving ecosystems away from PGP and towards solutions in the Sigstore ecosystem, so this is definitely not news to you. I understand you want the situation to change, but for now it's disingenuous to pretend like GPG in particular doesn't have the super majority of "market" share around signatures and that drama like this wouldn't have potential impact to a lot of folks.
It's interesting to consider third parties who maintain Linux package repos, like Postgres https://ftp.postgresql.org/pub/repos/yum/
They distribute their public keys on their own web infrastructure, so it's effectively TOFU. In your criticism of PyPI, you rightly pointed out that keys are useless unless pushed to a publicly-known key server because they aren't discoverable for users, which leads to ~no one verifying installs. I agree with this for PyPI, but in Postgres' case, if you do not have their key pulled locally, installs will fail by default. This means that users do generally install keys locally (actually they typically install the repo RPMs which configures local repositories as well as installs keys), even if the discovery mechanism isn't enforced by yum. My point here is that ecosystems without the ability to pre-bake rings of trust can still result in ~all downloads being verified as long as the client tooling defaults to the correct thing. pip not doing so is the main reason why OpenPGP signing never caught on in the Python ecosystem.
But yes, I agree: A modern day dpkg and rpm could swap to something with safer cryptography rather easily without changing anything about distribution. OpenPGP is a lot of bloat for their needs.
> Out of curiosity: which government standards? I'm not aware of a US Gov't standard that mandates PGP; this would be very valuable to know.
I don't believe any mandate OpenPGP specifically. I was more trying to get across that many institutions mandate FIPS 140-2/3, and current implementations (like on RHEL) complain if signatures are not present in their expected format. Because OpenPGP is my only choice for signing yum infrastructure and RPMs, it's a de-facto government standard today.