Key storage and revocation in a secure memory system
AssigneeFreescale Semiconductor, Inc.
InventorsRichard Soja, Nancy H. Amedeo, Timothy J. Strauss
Life of this patent
Estimating the term…
Abstract
A technique for providing access to a first storage structure of a system includes exposing a first key of a plurality of first keys stored in a second storage structure in response to a select code based on a plurality of corresponding select records stored in one-time programmable storage elements of the second memory structure. The technique includes providing the first key as a current first key of a memory access controller. Only one of the plurality of first keys stored in the second storage structure may be exposed at a time and other first keys of the plurality of first keys stored in the second storage structure are inaccessible from the second storage structure at the time.
Claims20
An apparatus comprising:
- a memory controller configured to provide information from a first storage structure in response to authentication of an access to the first storage structure, the authentication being based on a current first key of a plurality of first keys;
- a second storage structure configured to store the plurality of first keys and a plurality of corresponding select records in corresponding one-time programmable storage elements;
- and
- a key controller configured to expose, to the memory controller, a first key of the plurality of first keys stored in the second storage structure, in response to a select code based on the plurality of corresponding select records, the memory controller being configured to use the first key as the current first key.
A method comprising:
- providing access to a first storage structure in response to authentication of a memory request to the first storage structure, the authentication being based on a current first key of a plurality of first keys stored in a second storage structure;
- and
- exposing a first key of a plurality of first keys as the current first key in response to a select code based on a plurality of corresponding select records stored in one-time programmable storage elements of the second memory structure.
A method for providing access to a first storage structure of a system, the method comprising:
- controlling access to the first storage structure using a current first key of a plurality of first keys stored in a second storage structure;
- and
- exposing to a memory controller a next first key of the plurality of first keys as the current first key in response to a successful challenge of a received updated first key with the next first key and preventing exposure of the next first key from the plurality of first keys until expiration of a predetermined period of time in response to an unsuccessful challenge of the received updated first key with the next first key.
Dependencies are inferred from the claim text.