Systems and methods for updating a secure boot process on a computer with a hardware security module

A method for recovering a secure computer boot process on a computer comprising a Hardware Security Module (HSM) that accesses recorded values, compares submitted values indicative of at least one measurement to the recorded values, and releases a sealed secret (a released secret) if the submitted values are correct, said method comprising:

• A. securely booting a computer, comprising:
• i. measuring data involved in a boot process;
• ii. submitting a measurement of said data to the HSM;
• iii. requesting release of the sealed secret from the HSM, wherein said instructions for securely booting a computer cannot successfully complete a normal boot operation without said secret;
• iv. releasing the sealed secret only if the measurement submitted to the HSM is correct when compared to a recorded value, wherein the released sealed secret is different from the measurement and the recorded value;
• B. updating said data involved in a boot process, comprising:
• i. migrating the released secret to temporary storage where it remains while the data involved in the boot process is updated;
• ii. measuring updated data involved in the boot process;
• iii. restricting access to the migrated released secret by resealing it using the measurement of the updated data involved in the boot process, wherein the secret may be subsequently obtained by submitting at least a measurement of said updated data to the HSM.

A computer comprising a Hardware Security Module (HSM) that accesses recorded values, compares submitted values indicative of at least one measurement to the recorded values, and releases a sealed secret (a released secret) if the submitted values are correct, said computer comprising:

• A. means for securely booting a computer, comprising:
• i. means for measuring data involved in a boot process;
• ii. means for submitting a measurement of said data to the HSM;
• iii. means for requesting release of the sealed secret from the HSM, wherein said means for securely booting a computer cannot successfully complete a normal boot operation without said secret;
• iv. means for releasing the sealed secret only if the measurement submitted to the HSM is correct when compared to a recorded value, wherein the released sealed secret is different from the measurement and the recorded value;
• B. means for updating said data involved in a boot process, comprising:
• i. means for migrating the released secret to temporary storage where it remains while the data involved in the boot process is updated;
• ii. means for measuring updated data involved in the boot process;
• iii. means for restricting access to the migrated released secret by resealing it using the measurement of the updated data involved in the boot process, wherein the secret may be subsequently obtained by submitting at least a measurement of said updated data to the HSM.