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If the owner of a device can't sign and install their own software, then your definition of PKI doesn't "work" at all. The first party must be able to entirely

If the owner of a device can't sign and install their own software, then your definition of PKI doesn't "work" at all. The first party must be able to entirely decide that "some third party" for it to be anything more than an obfuscation of digital serfdom.

dijit 7mo ago
[flagged]
- Aachen 7mo ago
  > My definition of PKI is the one we’re using for TLS, some random array of “trusted” third parties can issue keys Maybe read the actual definition before assuming you're so much smarter than "HN". One doesn't need third parties to have pki, it's a concept, you can roll out your own
  - dijit 7mo ago
    “read the actual definition”;stellar contribution there, mate. I checked and sure enough its exactly in line with my comments. I’ve been discussing the practical implementation of PKI as it exists in the real world, specifically in the context of bootloader verification and TLS certificate validation. You know, the actual systems people use every day. But please, do enlighten me with whatever Wikipedia definition you’ve just skimmed that you think contradicts anything I’ve said. Because here’s the thing: whether you want to pedantically define PKI as “any infrastructure involving public keys” or specifically as “a hierarchical trust model with certificate authorities,” my point stands completely unchanged. In the context that spawned this entire thread, LineageOS and bootloader signature verification, there is a chain of trust, there are designated trusted authorities, and signatures outside that chain are rejected. That’s PKI. That’s how it works. That’s what I described. If your objection is that I should have been more precise about distinguishing between “Web PKI” and “PKI generally,” then congratulations on missing the forest for the trees whilst simultaneously contributing absolutely nothing of substance to the discussion. But sure, I’m the one who needs to read definitions. Perhaps you’d care to actually articulate which part of my explanation was functionally incorrect for the use case being discussed, rather than posting a single snarky sentence that says precisely nothing? EDIT: your edit is much more nuanced but still misses the point; https://imgur.com/a/n2VwltC https://imgur.com/a/n2VwltC
    - Aachen 7mo ago
      Good to know there's reply bots out there that copy out content immediately. I rarely run into edit conflicts (where someone reads before I add in another thing) but it happens, maybe this is why. Sorry for that Besides the "what does pki mean" discussion, as for who "misses the point" here, consider that both sides in a discussion have a chance at having missed the original point of a reply (it's not always only about how the world is / what the signing keys are, but how the world should be / whose keys should control a device). But the previous post was already in such a tone that it really doesn't matter who's right, it's not a discussion worth having anymore
    - bluebarbet 7mo ago
      The snarky tone and sarcasm are not helping your case in this thread.
      - dijit 7mo ago
        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.
        fc417fc802 7mo ago
        > 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.
- junon 7mo ago
  You misunderstood, it appears.
  - dijit 7mo ago
    Or its collective ignorance, can’t be sure. Public key infrastructure without CAs isn’t a thing as far as I can see, I’m willing to be proven wrong, but I thought the I in PKI was all about the CA system. We have PGP, but that's not PKI, thats peer-based public key cryptography.
    - eklavya 7mo ago
      I don't know what's going on in this thread. Of course PKI needs some root of trust. That root HAS to be predefined. What do people think all the browsers are doing? Lineage is signed, sure. It needs to be blessed with that root for it to work on that device.
      - junon 7mo ago
        They're assuming PKI is built on a fixed set of root CAs. That's not the case, as others have pointed out - only for major browsers. Subtle nuance, but their shitty, arrogant tone made me not want to elaborate.
        dijit 7mo ago
        "Subtle nuance" he says, after I've spent multiple comments explaining that bootloaders reject unsigned and untrusted-signed code identically, whilst he and others insist there's some meaningful technical distinction (which none of you have articulated). Then you admit you actually understood this the entire time, but my tone put you off elaborating. So you watched this thread pile on someone for being technically correct, said nothing of substance, and now reveal you knew they were right all along but simply chose not to contribute because you didn't like how they said it. That's not you taking the high road, mate. That's you admitting you prioritised posturing over clarity, then got smug about it. Brilliant contribution. Really moved the discourse forward there.
close04 7mo ago
The difference between “PKI” and “just signing with a private key” is the trusted authority infrastructure. Without that you still get the benefit of signatures and some degree of verification, you can still validate what you install. But in reality this trustworthiness check is handed over by the manufacturer to an infrastructure made up of these trusted parties in the owner’s name, and there’s nothing the owner can do about it. The owner may be able to validate software is signed with the expected key but still not be able to use it because the device wants PKI validation, not owner validation. I’ve been self-signing stuff in my home and homelab for decades. Everything works just the same technically but step outside and my trustworthiness is 0 for everyone else who relies on PKI.

dijit 7mo ago

[flagged]

Aachen 7mo ago
> My definition of PKI is the one we’re using for TLS, some random array of “trusted” third parties can issue keys Maybe read the actual definition before assuming you're so much smarter than "HN". One doesn't need third parties to have pki, it's a concept, you can roll out your own
- dijit 7mo ago
  “read the actual definition”;stellar contribution there, mate. I checked and sure enough its exactly in line with my comments. I’ve been discussing the practical implementation of PKI as it exists in the real world, specifically in the context of bootloader verification and TLS certificate validation. You know, the actual systems people use every day. But please, do enlighten me with whatever Wikipedia definition you’ve just skimmed that you think contradicts anything I’ve said. Because here’s the thing: whether you want to pedantically define PKI as “any infrastructure involving public keys” or specifically as “a hierarchical trust model with certificate authorities,” my point stands completely unchanged. In the context that spawned this entire thread, LineageOS and bootloader signature verification, there is a chain of trust, there are designated trusted authorities, and signatures outside that chain are rejected. That’s PKI. That’s how it works. That’s what I described. If your objection is that I should have been more precise about distinguishing between “Web PKI” and “PKI generally,” then congratulations on missing the forest for the trees whilst simultaneously contributing absolutely nothing of substance to the discussion. But sure, I’m the one who needs to read definitions. Perhaps you’d care to actually articulate which part of my explanation was functionally incorrect for the use case being discussed, rather than posting a single snarky sentence that says precisely nothing? EDIT: your edit is much more nuanced but still misses the point; https://imgur.com/a/n2VwltC https://imgur.com/a/n2VwltC
  - Aachen 7mo ago
    Good to know there's reply bots out there that copy out content immediately. I rarely run into edit conflicts (where someone reads before I add in another thing) but it happens, maybe this is why. Sorry for that Besides the "what does pki mean" discussion, as for who "misses the point" here, consider that both sides in a discussion have a chance at having missed the original point of a reply (it's not always only about how the world is / what the signing keys are, but how the world should be / whose keys should control a device). But the previous post was already in such a tone that it really doesn't matter who's right, it's not a discussion worth having anymore
  - bluebarbet 7mo ago
    The snarky tone and sarcasm are not helping your case in this thread.
    - dijit 7mo ago
      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.
      - fc417fc802 7mo ago
        > 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.
junon 7mo ago
You misunderstood, it appears.
- dijit 7mo ago
  Or its collective ignorance, can’t be sure. Public key infrastructure without CAs isn’t a thing as far as I can see, I’m willing to be proven wrong, but I thought the I in PKI was all about the CA system. We have PGP, but that's not PKI, thats peer-based public key cryptography.
  - eklavya 7mo ago
    I don't know what's going on in this thread. Of course PKI needs some root of trust. That root HAS to be predefined. What do people think all the browsers are doing? Lineage is signed, sure. It needs to be blessed with that root for it to work on that device.
    - junon 7mo ago
      They're assuming PKI is built on a fixed set of root CAs. That's not the case, as others have pointed out - only for major browsers. Subtle nuance, but their shitty, arrogant tone made me not want to elaborate.
      - dijit 7mo ago
        "Subtle nuance" he says, after I've spent multiple comments explaining that bootloaders reject unsigned and untrusted-signed code identically, whilst he and others insist there's some meaningful technical distinction (which none of you have articulated). Then you admit you actually understood this the entire time, but my tone put you off elaborating. So you watched this thread pile on someone for being technically correct, said nothing of substance, and now reveal you knew they were right all along but simply chose not to contribute because you didn't like how they said it. That's not you taking the high road, mate. That's you admitting you prioritised posturing over clarity, then got smug about it. Brilliant contribution. Really moved the discourse forward there.

close04 7mo ago

The difference between “PKI” and “just signing with a private key” is the trusted authority infrastructure. Without that you still get the benefit of signatures and some degree of verification, you can still validate what you install. But in reality this trustworthiness check is handed over by the manufacturer to an infrastructure made up of these trusted parties in the owner’s name, and there’s nothing the owner can do about it. The owner may be able to validate software is signed with the expected key but still not be able to use it because the device wants PKI validation, not owner validation. I’ve been self-signing stuff in my home and homelab for decades. Everything works just the same technically but step outside and my trustworthiness is 0 for everyone else who relies on PKI.