Other

University of California

Whole Sky Technologies Company

Daniel Shawcross Wilkerson

Mark William Winterrowd

Steve Fink

Alex Aiken

Anthony Tomasic

Joel Auslander

John David Kubiatowicz

Saul Schleimer

Modifications to existing computer hardware, compiler changes or source-to-source transforms performed during the software build process, and a collection of libraries and modifications to existing standard system software and libraries. The invention allows a program author to enforce various kinds of locality of causality in software to provide enforcement of boundaries for the following aspects of a computer program: control, space, time, modularity, reference, initialization, and mutability. Where these properties do not suffice to guarantee a property at static time, dynamic checks may be added and the constraints on control flow prevent such dynamic checks from being avoided by the program.

Hardware enforcement of boundaries on the control, space, time, modularity, reference, initialization, and mutability aspects of software

A method providing simple fine-grain hardware primitives with which software engineers can efficiently implement enforceable separation of programs into modules and constraints on control flow, thereby providing fine-grain locality of causality to the world of software. Additionally, a mechanism is provided to mark some modules, or parts thereof, as having kernel privileges and thereby allows the provision of kernel services through normal function calls, obviating the expensive prior art mechanism of system calls. Together with software changes, Object Oriented encapsulation semantics and control flow integrity in hardware are enforced.

Hard object: constraining control flow and providing lightweight kernel crossings

A hardware-implemented method to support three desirable software properties: encapsulation, referential integrity/capabilities, and transactions. These properties in turn may be used to support software correctness, specifically the enforcement of invariants, and computer security, specifically protecting parts of programs from each other within a single process.

Hard object: lightweight hardware enforcement of encapsulation, unforgeability, and transactionality

In accordance with one embodiment, additions to the standard computer microprocessor architecture hardware are disclosed comprising novel page table entry fields, special registers, instructions for modifying these fieldsand registers, and hardware-implementedruntime checks and operations involving these fields and registers. More specifically, in the above embodiment of a Hard Object system, there is additional meta-datain each page table entry beyond what it commonly holds, and each time a data load or store is issued from the CPU, and the virtual addresstranslated to the physical address, the Hard Object system uses its additional PTE meta-datato perform memory access checks additional to those done in current systems. Together with changes to software, these access checks can be arranged carefully to provide more fine-grain access control for data than do current systems.

Hard object: hardware protection for software objects

Methods and related systems for indexing the contents of documents for comparison with the contents of other documents to identify matching content. A method for comparing the contents of a query document to the content on the World Wide Web is set forth. The contents of a query document are indexed and compared to content from the World Wide Web which is continuously retrieved and indexed. The method for indexing may comprise selecting substrings from the document, hashing the substrings to generate a plurality of hash values having a known range of values, selecting certain hash values to save from the generated hash values, and sorting the saved hash values. Methods for selecting certain hash values to save are set forth.

Growing community of inventors

Berkeley, CA, United States of America

Daniel Shawcross Wilkerson