On Thu, 2025-07-24 at 21:14 +0000, Huang, Kai wrote: > > > > > > > > > > > > > Attempt to execute ENCLS[EUPDATESVN] every time the first file > > > > descriptor > > > > is obtained via sgx_(vepc_)open(). In the most common case the microcode > > > > SVN is already up-to-date, and the operation succeeds without updating > > > > SVN. > > > > > > (Sorry I forgot to say this in the previous versions): > > > > > > If I read the pseudo code correctly, when the SVN is already up-to-date, > > > the EUPDATESVN doesn't update SVN but it re-generates crypto assets > > > anyway. > > > > > > This is no harm per the pseudo code, since the "crypto assets" is actually > > > the CR_BASE_KEY which is only used by EWB/ELDU flow per the SDM. > > > > > > In other words, it doesn't impact other enclave visible keys (those from > > > EGETKEY) such as sealing key. > > > > > > I think this is important. Because if enclave visible keys such as > > > sealing key are lost on EUPDATESVN when SVN is already up-to-date (which > > > is the most common case), it will bring significant visible impact to > > > enclave. E.g., one enclave could find its secret encrypted by sealing key > > > could never be retrieved after it restarts. > > > > > > Assuming I didn't miss anything, can we also mention this in the > > > changelog? > > > > Yes, you are right, anything like above behaviour would be a nightmare > > in practice. So would smth like this work as an additional text: > > > > "Note that in cases when SVN is already up-to-date and EUPDATESVN > > is executed, it does not affect enclaves' visible keys obtained via EGETKEY > > instruction." > > > > ? > > > > Yes works for me. Thanks.
Side topic, just out of curiosity, do you know why Intel decided to re- generate CR_BASE_KEY even SVN is found to be up-to-date?
