> On Feb 10, 2023, at 6:05 AM, Mimi Zohar <zohar@xxxxxxxxxxxxx> wrote: > > Hi Eric, > > On Mon, 2023-02-06 at 21:59 -0500, Eric Snowberg wrote: >> Add a machine keyring CA restriction menu option to control the type of >> keys that may be added to it. The options include none, min and max >> restrictions. >> >> When no restrictions are selected, all Machine Owner Keys (MOK) are added >> to the machine keyring. When CONFIG_INTEGRITY_CA_MACHINE_KEYRING_MIN is >> selected, the CA bit must be true. Also the key usage must contain >> keyCertSign, any other usage field may be set as well. >> >> When CONFIG_INTEGRITY_CA_MACHINE_KEYRING_MAX is selected, the CA bit must >> be true. Also the key usage must contain keyCertSign and the >> digitialSignature usage may not be set. >> >> Signed-off-by: Eric Snowberg <eric.snowberg@xxxxxxxxxx> > > Missing from the patch description is the motivation for this change. > The choices none, min, max implies a progression, which is good, and > the technical differences between the choices, but not the reason. > > The motivation, at least from my perspective, is separation of > certificate signing from code signing keys, where "none" is no > separation and "max" being total separation of keys based on usage. > > Subsequent work, as discussed in the cover letter thread, will limit > certificates being loaded onto the IMA keyring to code signing keys > used for signature verification. I will include this in the next round too, thanks.