Patent · US Active

Emulation-based software protection

US8285987B1 · kind B1 · utility

26Cited by
5References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 4, 2009
Grant dateOct 9, 2012
Priority date
Expiry dateMay 26, 2031

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F21/14
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method of emulation-based page granularity code signing comprising the steps of: copying guest operating system instructions and associated hash message authentication codes and/or digital signatures of each guest operating instruction from an untrusted guest operating system memory into a trusted host operating system memory; recomputing the hash message authentication codes using a secret key in the trusted host operating system memory; maintaining the secret key in the trusted host operating system memory and inaccessible by the untrusted guest operating system instructions; translating each guest operating system instruction that has a valid hash message authentication code to a set of host operating system instructions; executing the decrypted guest operating system instructions in the trusted host operating system; and modifying the guest operating system memory and registers when the set of translated host operating instructions executes in the trusted host operating system, such that it appears as if the original guest operating system instructions had been executed in the untrusted guest operating system.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.