On Sat, Nov 24, 2018 at 08:15:21AM -0800, Jarkko Sakkinen wrote: > On Tue, Nov 20, 2018 at 05:15:08AM -0600, Dr. Greg wrote: > > Malware would not necessarily need the Intel attestation service. > > Once access to the PROVISION bit is available, malware teams could > > simply build their own attestation service. > AFAIK not possible as they wouldn't have access to the root > provisioning key. Can be confirmed from the SDM's key derivation > table (41-56). What provisioning and attestation is all about is establishing an identity binding for a platform in question. The standard Intel service binds the identity of a platform to an EPID private key. With access to the SGX_FLAGS_PROVISION_BIT an enclave can generate a perpetual identity for a platform based on the identity modulus signature (MRSIGNER) of the key that signs the signature structure of the enclave. Without access to the root provisioning key a security quorum or group has to be implemented via a subscription or enrollment model but that is arguably not much of an obstacle. That is pretty much the way standard botware works now. Without provisions for cryptographically secure authorization and policy enforcement in the driver, we will be creating infrastructure for a new generation of botware/malware whose mothership will know that a participating platform is running with full confidentiality and integrity protections. > /Jarkko Dr. Greg As always, Dr. G.W. Wettstein, Ph.D. Enjellic Systems Development, LLC. 4206 N. 19th Ave. Specializing in information infra-structure Fargo, ND 58102 development. PH: 701-281-1686 FAX: 701-281-3949 EMAIL: greg@xxxxxxxxxxxx ------------------------------------------------------------------------------ "Remember that when you take down the fishhouse you can't put the minnows back into the lake, so throw them out on the ice. Make sure you stomp on any of the live ones so they don't suffer." -- Fritz Wettstein At the lake