On Thu, 2014-06-12 at 13:00 -0400, Vivek Goyal wrote: > On Thu, Jun 12, 2014 at 12:55:26PM -0400, Mimi Zohar wrote: > > On Thu, 2014-06-12 at 12:03 -0400, Vivek Goyal wrote: > > > On Tue, Jun 10, 2014 at 11:48:17AM +0300, Dmitry Kasatkin wrote: > > > > This patch provides kernel parameter to specify owner's key id which > > > > must be used for trust validate of keys. Keys signed with other keys > > > > are not trusted. > > > > > > > > Signed-off-by: Dmitry Kasatkin <[email protected]> > > > > > > Hi, > > > > > > I am continuing to work on verifying kernel signature for kexec/kdump. I > > > am planning to take david howell's patches for pkcs7 signature > > > verification and verify bzImage signature. > > > > > > Part of that process will boil down to verifying a certificate in > > > pkcs7 x509 cert chain using a key in system_trusted_keyring. > > > > > > I think the OS vendor key which signs the kernel signing key propagates to > > > system_trusted_keyring. (shim has that and I am not sure how shim makes > > > it propogate all they way to system_trusted_keyring). > > > > The shim patches are here > > http://pkgs.fedoraproject.org/cgit/kernel.git/tree/modsign-uefi.patch > > > > > So I was planning to use same functionality where I look for any key > > > which can verify the signing cert of kernel. As OS vendor key will be > > > in system_trusted_keyring, it should work. > > > > > > Now with this change where you will trust only one selected owner key. > > > That means you will not even trust the OS vendor key which signs kernel > > > signing key. I think this will stop working with keys_ownerid=<....> > > > > > > As I am doing that work in parallel and I saw these patches, I thought > > > I will bring it up. > > > > Right, the current discussion is whether we need an owner trusted > > keyring or if just one key was enough. Thanks for chiming in. > > > > The other option would be to sign the bzImage file creating a > > 'security.ima' extended attribute and verifying it. Have you created a > > security kexec hook? > > No, I have not created another hook. As bzImage is already signed it is > much simpler to verify same signature instead of carrying another set > of detached signatures and key management etc.
Fin (cc'ed) has patches that include the file signatures in the RPM header and installs them. There wouldn't be any need for a separate detached signature. Mimi -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
