Patent ID: 8850212

Claim:
A method of extending an integrity measurement in a trusted device operating in a trusted platform by using a set of policy commands to: extend into a policy register: a list of Platform Configuration Registers (PCRs) for the device, current values of the listed PCRs, an integrity value identifying the integrity measurement, and a PCR, from the list of PCRs, intended to be extended into the policy register; verify a signature over the integrity value extended into the policy register, and, when verification succeeds, extend a verification key of the trusted platform, plus an indication that it is a verification key, into the policy register, wherein verifying the signature is performed using a first verification public key and wherein the verification key extended into the policy register is the first verification public key plus an indication that it is a verification key; compare the integrity value extended into the policy register with a value stored in the trusted platform, and, when the compared values are the same: extend the stored value, plus an indication that it is a stored value, into the policy register; and extend the integrity measurement in the trusted device when the stored value in the policy register matches a value stored with the integrity measurement.