The tone matched the engagement I received. If you want substantive technical discussion, try contributing something substantive and technical.
I've explained the same point three different ways now. Not one person has actually demonstrated where the technical argument is wrong, just deflected to TOFU comparisons, philosophical ownership debates, and now tone policing.
If Aachen has an actual technical refutation, I'm all ears. But "read the definition" isn't one, and neither is complaining about snark whilst continuing to avoid the substance.
> I've explained the same point three different ways now.
But you're demonstrably wrong. The purpose of a PKI is to map keys to identities. There's no CA located across the network that gets queried by the Android boot process. Merely a local store of trusted signing keys. AVB has the same general shape as SecureBoot.
The point of secure boot isn't to involve a third party. It's to prevent tampering and possibly also hardware theft.
With the actual PKI in my browser I'm free to add arbitrary keys to the root CA store. With SecureBoot on my laptop I'm free to add arbitrary signing keys.
The issue has nothing to do with PKI or TOFU or whatever else. It's bootloaders that don't permit enrolling your own keys.
> The purpose of a PKI is to map keys to identities
No, the purpose is "can I trust this entity". The mapping is the mechanism, not the purpose.
> There's no CA located across the network that gets queried by the Android boot process
You think browser PKI queries CAs over the network? It doesn't. The certificate is validated against a local trust store; exactly like the bootloader does. If it's not signed by a trusted authority in that store, it's rejected. Same mechanism.
> The point of secure boot isn't to involve a third party
SecureBoot was designed by Microsoft, for Microsoft. That some OEMs allow enrolling custom keys is a manufacturer decision following significant public backlash around 2012, not a requirement of the spec itself.
> The issue has nothing to do with PKI [...] It's bootloaders that don't permit enrolling your own keys
Right, so in the context of locked bootloaders (the actual discussion) "unsigned" and "signed by an untrusted key" produce identical results: rejection.
Look I'm not even clear where you're trying to go with this. You honestly just come across as wanting to argue pointlessly.
You compared bootloader validation to TLS verification. The purpose of TLS CAs is to verify that the entity is who they claim to be. Nothing more, nothing less. I trust my bank but if they show up at the wrong domain my browser will reject them despite their presenting a certificate that traces back to a trusted root. It isn't a matter of trust it's a matter of identity.
Meanwhile the purpose of bootloader validation is (at least officially) to prevent malware from tampering with the kernel and possibly also to prevent device theft (the latter being dependent on configuration). Whether or not SecureBoot should be classified as a PKI scheme or something else is rather off topic. The underlying purpose is entirely different from that of TLS.
> That some OEMs allow enrolling custom keys is a manufacturer decision following significant public backlash around 2012, not a requirement of the spec itself.
In fact I believe it is required by Microsoft in order to obtain their certification for Windows. Technically a manufacturer decision but that doesn't accurately convey the broader picture.
Again, where are you going with this? It seems as though you're trying to score imaginary points.
> Where exactly am I "demonstrably wrong"?
Your claimed that the point of SecureBoot is to involve a third party. It is not. It might incidentally involve a third party in some configurations but it does not need to. The actual point of the thing is to prevent low level malware.
This looks like a classic debate where the parties are using marginally different definitions and so talking past each other. You're obviously both right by certain definitions. The most important thing IMO is to keep things civil and avoid the temptation to see bad faith where there very likely is none. Keep this place special.
