On Wed, May 15, 2024 at 12:44 AM Jarkko Sakkinen <jarkko@xxxxxxxxxx> wrote: > > On Wed May 15, 2024 at 2:10 AM EEST, Jarkko Sakkinen wrote: > > On Sat May 4, 2024 at 1:16 AM EEST, Ignat Korchagin wrote: > > > Derived keys are similar to user keys, but their payload is derived from the > > > primary TPM seed and some metadata of the requesting process. This way every > > > > What is exactly "some metadata"? > > > > > application can get a unique secret/key, which is cryptographically bound to > > > > What is "cryptographically bound". Please go straight to the point and > > cut out *all* white paper'ish phrases. We do not need it and will make > > painful to backtrack this commit once in the mainline. > > > > > the TPM without the need to provide the key material externally (unlike trusted > > > keys). Also, the whole key derivation process is deterministic, so as long as > > > > Why trusted keys is inside braces. It is not important for the point > > you are trying to make here? > > > > > the TPM is available, applications can always recover their keys, which may > > > allow for easier key management on stateless systems. > > > > Please drop "stateless system" unless you provide a rigid definition > > what it is. I have no idea what you mean by it. Probably not that > > important, right? > > > > > > > > In this implementation the following factors will be used as a key derivation > > > factor: > > > * requested key length > > > * requesting process effective user id > > > * either the application executable path or the application integrity > > > metadata (if available) > > > > NAK for path for any possible key derivation. They are racy and > > and ambiguous. > > > > This should have been in the beginning instead of "some data". What > > other implementations exist. For me "this implementation" implies > > that this one competing alternative to multiple implementations > > of the same thing. > > > > I do not like this science/white paper style at all. Just express > > short, open code everything right at start when you need and cut > > extras like "stateless system" unless you can provide exact, sound > > and unambiguous definiton of it. > > > > Just want to underline how this really needs a complete rewrite with > > clear and concise explanation :-) This won't ever work. > > > > > > > > Key length is used so requests for keys with different sizes result in keys > > > with different cryptographic material. > > > > What is "key length"? Please refer the exact attribute. > > > > > > > > User id is mixed, so different users get different keys even when executing the > > > > First of all it would be more clear to just s/User id/UID/ > > > > And make obvious whether we are talking about ruid or euid and how > > this interacts with GIDs. > > > > I'll look at the code change next round if the commit message starts > > making any sense. > > Right and neither UIDs and GIDs are applicable for key derivation for > quite obvious reasons. So NAK for that too. Can you, please, clarify a bit here? Not very obvious for me. I added euid for two reasons: * an unprivileged user might run a normally privileged application, for example /usr/sbin/sshd, and depending on the code could "leak" the key * without it and with unprivileged user namespaces it is possible to create an unprivileged container with code at the same path as a privileged application Why do you think UIDs/GIDs are not applicable as mixins? Ignat > You can make them point out unlimited different identities... > > BR, Jarkko
