A trust
system and method is disclosed for use in computing devices, particularly portable devices, in which a
central Authority shares secrets and sensitive data with users of the respective devices. The
central Authority maintains control over how and when shared secrets and data are used. In one embodiment, the secrets and data are protected by hardware-rooted
encryption and cryptographic hashing, and can be stored securely in untrusted storage. The problem of transient trust and
revocation of data is reduced to that of secure
key management and keeping a runtime check of the integrity of the secure storage areas containing these keys (and other secrets). These hardware-protected keys and other secrets can further protect the
confidentiality and / or integrity of any amount of other information of arbitrary size (e.g., files, programs, data) by the use of strong
encryption and / or keyed-hashing, respectively. In addition to secrets the Authority owns, the
system provides access to
third party secrets from the computing devices. In one embodiment, the hardware-rooted
encryption and hashing each use a single
hardware register fabricated as part of the computing device's processor or
System-on-
Chip (SoC) and protected from external probing. The secret data is protected while in the device even during
operating system malfunctions and becomes non-accessible from storage according to various rules, one of the rules being the passage of a certain time period. The use of the keys (or other secrets) can be bound to security policies that cannot be separated from the keys (or other secrets). The Authority is also able to establish remote trust and secure communications to the devices after deployment in the field using a special tamper-resistant
hardware register in the device, to enable, disable or update the keys or secrets stored securely by the device.