Input/output permission bitmaps for compartmentalized security
US7493498B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 27, 2002 |
| Grant date | Feb 17, 2009 |
| Priority date | — |
| Expiry date | Aug 3, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F12/1491
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for selectively executing an I/O instruction. The method includes creating an I/O permission bitmap in a memory and receiving an I/O port number and a security context identification (SCID) value. The method also includes using the SCID value and the I/O port number to access the I/O permission bitmap stored to obtain a permission bit corresponding to the I/O port and executing the I/O instruction dependent upon a value of the permission bit corresponding to the I/O port. The I/O permission bitmap includes a plurality of permission bits. Each of the permission bits corresponds to a different one of a plurality of I/O ports. Each of the permission bits has a value indicating whether access to the corresponding I/O port is allowed. The I/O port number indicates the I/O port referenced by the I/O instruction. The SCID value indicates a security context level of a memory location including the I/O instruction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.